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Q from Kort, UT (8/28/20) -

Last fall I planted about a dozen chokecherries in my yard and a few of them are dying. Is that something you could help me with?

The stems get this dark, sappy mark and then eventually die. There's very small bugs crawling around in the soil near the wound Help!

Thank you,

Kort

A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 9/1/20) -

Kort,

At least one of the trees (the first shown) has a stem canker right at the ground line and it looks like it has girdled and killed more than half of the circumference of the largest stem. Many members of the cherry genus in the rose family are very susceptible to diseases, including fungal cankers. They usually will cause some brown, clear exudation where the canker is in the tree. This exudation is called gummosis, but it is more of a symptom than a disease itself. Gummosis can be caused by a canker, but it can also be caused by physical damage to the stem or many other things.

It is not clear to me whether the trees were planted too deeply, or if I am just seeing a multi stemmed tree. However, usually the branching for a multi stemmed tree occurs above ground. So check on whether they are planted too deeply now, or whether they were actually grown too deeply, which unfortunately is fairly common.

I suspect that your trees came from the nursery with cankers, but it would be hard to tell at this point. All you can do now is make sure that the trees are getting enough water so they have a chance of outgrowing the canker. If the root collars were planted or grown too deeply then it may be possible to remove the surface soil and expose the root collars.

Good luck!

Mike Kuhns


Q from Unknown, (8/28/20) -

Can you use Sycamore leaves and a compost pile? This is one of the first years I have been able to get my temperature up in my compost pile. I have heard both comments stating you can  and cannot use the leaves because of fungi  and mold diseases. Can I use my compost pile in my garden next year in Spring?


A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 8/28/20) -

I suspect that people worry because there is a common disease that attacks sycamores called sycamore anthracnose. It is a fungus that infests the newly emerging leaves and twigs in the spring. There are a few diseases that you have to protect against through sanitation — raking up leaves from under the trees and keeping it clean. This happens to be the case with sycamore anthracnose. However, if you are going to compost the material you clean up then it doesn’t matter because the composting process usually kills any live parts of the fungus that would allow it to reproduce (like spores and fungal strands).

Good luck!

Mike Kuhns


Q from Dave, UT (8/26/20) -

Today I had a tree trimming company come out and look at my Maple tree. I think he is an arborist by training and education. I told him that I had treated the tree with Bayer insect treatment this spring and a second treatment in late May. He saw no evidence of bore holes in the tree. He thinks it may be a fungus of some type perhaps Sylibus?(Probably not the correct spelling or perhaps word). Any way he said it originated in the ground, was a fungus and ran up the cannulas and plugged it off the pores, which killed off the branches quite slowly. What if I used powdered bleach, like for a hot tub or swimming pool, and have the roots take it up, would that work? Let me know if removal is the only remedy.

My questions to you are:
1.      Is there a cure for this if what is ailing the tree if it is a fungus?
2.      He said the cost of looking at the soil for evidence of the fungus will cost $200 to $250. Is this a realistic cost?
3.      Is there anything I can do to fix the problem?




A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 8/28/20) -

David,

Your tree looks like a Norway maple, and it has a large limb that has died. Also, in 2 of the pictures you can see a fairly large pruning wound from a cut that was made about a year ago near the point of attachment of the dead limb. In my experience with Norway maples, significant canopy dieback is common as the trees get older and less vigorous and especially if significant pruning is done and especially if it is done in the summer and if that pruning opens up the tree’s canopy so that it gets lots more sun than in the past. So this will keep happening, and the only thing that can be done about it is to prune in the winter or early spring and prune branches early so that you are never cutting branches bigger than about 2” in diameter.

As for what you have done or are thinking about doing, it is best to deal with an ISA Certified Arborist. You should only treat trees for known problems and with appropriate materials and treatments. Your insecticide treatments likely have no effect, other than maybe killing some aphids, which, though they can be a nuisance in Norway maples, I do not think that they are worth treating for. There are no significant borers that attack this species. Though there may be a stem canker fungus that is involved with the pruning-related dieback, I have not heard of one and the way he/she describe the fungus, originating in the ground, running up the cannulas and plugged it off the pores, and killing off the branches slowly, sounds bogus. Needless to say, paying $200-250 to look for it in the soil will not do any good, but it won’t be the only expense. He will find something and will want to treat it for lots more money. Also, do not put powdered bleach in the soil; it will harm or kill the tree.

It seems to me that the is enough live canopy that you do not have to treat the tree or get rid of it. You should be able to have the dead wood pruned out every 2 or 3 years using my advice above.

Mike Kuhns


Q from Miles, Draper, UT (received 8/10/20) -

I have one white ash and 4 green ash trees in my yard. The green ash trees appear to have some bore holes in the bark on the trunk and the canopy is droopy and dying in places. Is there something I can do to help them out? What is going on?


A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 8/11/20) -

Miles,

Your green ashes have ash borer (also called lilac borer). It is a VERY common pest on ashes, and especially green ashes. The only treatment for them is to spray insecticide on their trunk and larger branches in the spring every year or two to kill the insects that are on the trunk and to block their entry. You can’t kill them once they are inside the tree. Unfortunately, the spray doesn’t block the entry of new ones very well either. This is the reason I rarely recommend planting of green ashes in Utah.

Mike Kuhns

Q from Codi (received 8/1/20) -

What is this on my young Washington Hawthorn? It was covered in ants. I was able to get rid of the ants, but I think they caused a burl, possibly. At least I am hoping that's what it is.

A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 8/3/20) -

Codi,

I think that your hawthorn likely has a fungal disease called cedar-hawthorn rust. This is similar to cedar-apple rust, which is more common. Diseases like these have two hosts, in your case a juniper or “cedar” and a hawthorn.  The fungus takes on a certain look and form in one host versus the other host. It attacks one species with a kind of spore produced by a certain fruiting body. Those spores can only attack the alternate host. Once they do this they produce a different spore from a different fruiting body that infests the original host. You can spray with fungicides if it gets too bad for you.

Thankfully, no form of either of these diseases is very harmful to either host. Nothing has to be done, but you may be able to prune out the most unsightly parts. You can spray with fungicides if it gets too bad for you.

There is good information on these diseases at https://www.missouribotanicalgarden.org/gardens-gardening/your-garden/help-for-the-home-gardener/advice-tips-resources/pests-and-problems/diseases/rusts/cedar-hawthorn-rust.aspx

Mike Kuhns


Q from Michelle, Florida (received 8/1/20) -

Greetings from Florida!

Good afternoon Dr. Kuhns. I saw one of your videos on youtube in regards to pruning a tree. I need to prune my Cassia Bakeriana tree but I am not able to find any videos on this specific tree. Are you able to look at the attached pictures and maybe circle or make an arrow on what branches you think I should prune? My tree is growing branches but it doesn't seem to want to grow upwards.

You will see in one of the pictures i had placed an arrow by one of the branches I want to trim off but Im nervous about it. What do you think?

Thank you,

Michelle


A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 8/3/20) -

Michelle, Nothing needs to be pruned off of this tree unless you want it to have one trunk instead of 2. If 2 trunks then don’t do anything. If you keep the trunk that branches close to the ground, of course, you will have what is essentially a multi-trunked tree, and you may have more trunks as other stems emerge from the roots. You can decide what you want in this regard, though. There is no right answer.

There is no need to prune off any of the upper branches, though you can if you want.

Mike Kuhns

Q from Stephanie Sorenson (received 7/28/20) -

I planted 13 arborvitaes in early May. They were all doing really well up until a month ago. Now I think a couple of them have died or are really sick. They are watered twice a week right now for an hour at a time, due to the heat. They do sit on the north side of the yard. Our house was built 3 1/2 years ago. The trees on the ends seem to be doing really well, however the closer you get to the center the trees appear to be dying. We've had some one come look at them, however he is more of a tree trimming expert. He says the ones that look dead still have some bend to the branch, which indicates there is still water in the tree. He has been treating them with Osmocote and Super Thrive. I'm just not sure what is happening to these trees. Is there any hope?

Thanks,

Stephanie Sorenson


A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 7/28/20) -

Stephanie,

I like arborvitaes, but they are not very heat or drought tolerant. I think that it is likely that lack of water is the problem. The reason I can tell this is because I know that they need a lot of water, the weather now is very hot and dry, and combine that with something I saw in one of your photos — some brown tubing that I assume is how you are watering, meaning that you are using drip irrigation or something similar. Watering twice a week sounds pretty good, and for an hour each time sounds good. But it may not be nearly enough depending how much water is applied and where it is applied. For example, if you have one drip emitter for each tree at or near the tree’s base putting out 1-1/2 gallons per hour, that means that each tree is getting 3 gallons per week. With no other source of water, that seems to me not nearly enough.

So what you need to do is figure out how much water you are giving each tree and where it is going. You should be watering enough that the soil is moist and stays moist at least a foot deep and covers the entire soil area under the tree’s canopy. And since these trees really need wider coverage than that because of their narrow, upright form, you should probably apply water to at least twice the width of the canopy. Also, you need to irrigate more than enough for the tree’s’ needs now because they will need more water and access to more soil as they grow.

To give you an idea of what you are dealing with, a large tree like an arborvitae can use more than 100 gallons a day, and a very large tree can use 200 or 300 gallons a day. Drought hardy trees may like to have so much water available to them, but they can get by on quite a bit less. However, trees that do poorly when it gets hot and dry, like arborvitaes, are much more susceptible to attack by insects and diseases if they get stressed at all.

You can check how deeply and how wide your trees are being watered by shoving a steel probe, like a long screwdriver or other narrow steel rod into the soil all over our landscape. Such a probe will readily penetrate moist soil and will stop when it contacts dry soil.

So check your irrigation amounts and coverage. Also check that your trees were planted right by reviewing our tree planting factsheet at https://forestry.usu.edu/news/utah-forest-facts/planting-landscape-trees

Good Luck,

Mike Kuhns


Q from Ashley Heath, Vineyard, UT (received 7/27/20) -

We've got a redbud tree that's 1 to 2 years old and its leaves just started getting brown spots.


A from Dr. Mike Kuhns, USU Extension Forester and Professor (7/27/20) -

This tree has leaf scorch caused by it not getting enough water. Eastern redbud (which I assume is what this tree is) is native to wetter sites than we can grow them in here. If you had planted a Utah native western or California redbud instead and treated it similarly, it likely would not show this stress. Its genetics are different and it has biological traits that make it better-adapted to hot, dry conditions. On the other hand some tree species are so poorly adapted that they cannot take up enough water through their roots no matter how much they get. They also may take it up but do not control water loss from their leaves. Either way they will be stressed and may not be adequately adapted to your site.

So either water the tree more and mulch it with organic material to encourage good root growth, or consider another tree species that can withstand water stress better.

Mike Kuhns


Q from Linda Young, South Jordan, UT (received 7/21/20) -

We have Sycamore trees in our parkway in Daybreak. They are dropping lots of leaves and bark. This has never happened before. I did notice some what it appears to be aphids on some leaves as well. Any suggestions as to what might be wrong? The entire block of trees look that way. Thank you so much for your help on this matter.

Linda


A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 7/28/20) -

Linda,

The bark loss that occurs on London planetrees after they are a few years old is normal and will get more pronounced with time, but it doesn't matter. More bark will be made inside the current bark to replace what is lost. The leaf spots and curling are caused by a common disease called sycamore anthracnose. Though fungicidal treatments are available, generally I think that they are not necessary.

Mike Kuhns


Q from Kyle Jensen, Herriman, UT (received 7/16/20) -

I planted this tree 3 years ago.  I live in Herriman, Utah and this tree has been growing well over the last 2 years.  This year the new leaves are not looking good this year.  See photos.  It gets water from the sprinklers 3 times a week and I also water deep once a week   I fertilize with a triple 16 fertilizer once in the spring and once in the fall.

Thanks,

Kyle Jensen


A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 7/20/20) -

This is a London planetree. The trunk has some cankers or dieback caused either by disease or sun. I suggest that you read our factsheet on sunscald at http://forestry.usu.edu/files/utah-forest-facts/sunscald-injury-or-southwest-winter-injury-on-deciduous-trees.pdfWhatever damage was caused by it is starting to heal though. The curling of the leaves could be from several sources, but what is likely depends partly on the time of year that you took the pictures. If it was in spring it could be due to a fungal disease called anthracnose, though normally the leaves would have spots on them and the disease is mostly done by summer. It looks like it could be herbicide damage and particularly broadleaf weed killer like 2,4-D. If the leaves did not get any worse after the leaves were photographed then I doubt that it will have much long lasting impact on the tree’s health. Leaf problems are only as bad as the proportion of the photosynthesizing leaf tissue that is lost. These don’t look too bad. The damage will go a way after the leaves fall off and next year will start anew.

You likely are watering enough but you do not need to fertilize.

Good luck. 

Mike Kuhns


Q from Shelton Beach, Arco, ID (received 7/7/20) -

I have a windbreak of some 40 mature blue spruce trees...probably 50 feet tall.  They are planted in 2 rows.  The trees are fairly close together...about 5 feet apart.  If I run a drip hose down each side of the row of trees, will that be adequate?  Do I need to water around the trunks of the trees?

 

A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 7/15/20) -

Shelton,

Five feet apart is too close, especially if the rows are also 5 feet apart. They will be competing for water and light especially. Drip irrigation likely will not be adequate. These trees probably need a couple of hundred gallons of water a day each.  However you apply the water, it needs to moisten the soil near the trunks and at least put to the edge of the canopies. Besides watering adequately I suggest that you try to figure out a way to remove maybe half of the trees to make the remaining ones healthier. You may not be able to do this though because with the trees being grown so close together for so many years, their canopies will have mutually shaded each other to the point that what is left will not function well as a windbreak.

Good luck.  

Mike Kuhns

Q from Thom Dickeson, Taylorsville, UT (received 7/9/20) -

The blue spruce is about 35' tall and the arborvitae is about 17' feet tall.  The HOA says they need trimming.  I don't want to have to remove them.  Can either be shaped and maybe shortened successfully?  How long will it take to fill in areas that are down to exposed branches, especially the arborvitae?

Thanks for any help,

Thom


A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 7/15/20) -

Thom,

You can keep trees shorter than they would naturally get by shearing or pruning the tips of the branches. You have to do this every year, and it will not work to do it when the tree has gotten much larger than the desired size. It looks to me, though, like there is no need to keep these trees shorter. What is needed, and is being done already, is to prune the lower canopies to make room for pedestrians and to keep branches from rubbing agaInst buildings and that sort of thing. It looks to me like you have been doIng that fairly well, but maybe telling them that you will prune more for clearance will satisfy them.

Mike Kuhns 


Q from Tye (received 7/1/20) -

I have a problem with a mountain Ash tree,  leaves curling with web like substance. I believe it is leaf curl ash aphids.

A from Zach Schumm, Utah Plant Pest Diagnostic Lab, Arthropod Diagnostician (received 7/1/20) -

The "fuzzy" critters are a type of woolly aphid (not sure of the species, but they all behave similarly), which can cause the leaves to curl. The fuzziness that these insects have are due to waxy secretions that they use to protect themselves, among other things.

The good news is that large (i.e., not saplings) healthy trees don't typically suffer at the hands of these aphids. If you're seeing the whole tree beginning to look like this, then you may want to think about some sort of management, but right now I don't think it's necessary if it's only on certain parts of the tree.

The other reason I am hesitant to control these insects with some sort of insecticide / chemical is because the other image you submitted with little "balls" on the end of web-like stalks are lacewing larva eggs. These larvae are voracious predators of soft bodied insects, and they absolutely love to eat aphids. If you spray to control the aphids, you can also kill the lacewings that are beneficial and offering natural control of the aphids that will (probably) prevent them from damaging more areas of the tree. These eggs are actually super interesting. They are laid on the stalks so that predatory insects (such as ants) have a hard time reaching them and eating them. So, you'll want to keep the lacewing eggs around.

You can just remove the aphid-infested leaves with pruners if you wish (I know the curled areas are unsightly). Unless most of the tree is heavily infested, I don't think there is a ton to worry about right now, especially with knowing that predatory insects are in the area!

Here are some links to some information pages and fact sheets on these insects:

Woolly aphids (ash example): https://www.ag.ndsu.edu/cpr/horticulture/ash-leaf-curl-aphids-in-ash-trees-6-14-12

Woolly apple aphid (a specific species that can be a pest on ash): https://fctreecare.com/pest-care/woolly-apple-aphid.html 

Fact sheet on lacewings / antlions: https://utahpests.usu.edu/uppdl/files-ou/factsheet/beneficial-insects_lacewings-and-antlions.pdf

Let me know if you have any further questions! 

Best, 

Zach Schumm


Q from Angela (received 6/19/20) -

I have some brown spots coming up on the leaves of two recently planted apple trees (a honey crisp and a braeburn). Do you know what the problem would be? Thank you for your help!


A from Marion Murray, Utah Extension Integrated Pest Management (sent 6/19/20) - 

That is a fungal disease called apple scab. Although it is around, we rarely see it causing any damage on Utah apple trees because of the hot, dry weather.  But when conditions are like what we have had in June (cold and rainy), then it can show up.

The weather is expected to get hot and dry again, so the fungus will not continue to spread.  Therefore, a fungicide application is not warranted.  The leaves showing infection now will remain as they are, but there shouldn’t be any more spread.

However, if you use irrigation that lands on the foliage, then yes, this will cause further spread and a fungicide is warranted.

The disease may show up next spring, so you can use Spectracide Immunox right after bloom, and repeat 2 weeks later.

Feel free follow up with me if any more questions arise.

Take care,

Marion Murray


Q from Mark, Sandy, UT (received 6/1/20) -


I have what I think is a type of olive tree. It is  mature tree that appears to be dying. There are golf ball sized sappy bulbs all along the main trunks. Several of the main trunks no longer produce leaves or new growth and appear completely dead.

Can you tell me what caused this tree to die? If it is a disease, should I worry for the other trees around?

A from Gabrielle Harden,
USU Forestry Extension Educator (sent 6/2/20) -

This appears to be a Phomopsis canker which is caused by the fungus Phomopsis arnoldiaeBoth the tree and the disease are exotic to this region, and this tree species is actually invasive in the West. This disease is very difficult to manage. Branches with cankers can be pruned in winter or early spring. To ensure the disease does not spread to other trees, it is wise to burn the diseased portions removed, though I am not able to see any other Russian olives on the landscape. This looks like a rather serious infection, and I worry it may be too late to save this tree. It will become increasingly unsightly and eventually die. Unfortunately, removal may be your best bet.

This is a common issue out east, so a quick Google search for 'phomopsis canker Russian olive' will generate many articles from universities in that region.

I hope this helps.

Gabrielle Harden


Q from Larry, Longmont, CO (received 5/26/20) -

I planted a cluster of Aspen trees last November. They are growing nicely, however the tallest one seems to have no center stem at the top. Rather than having one main stem growing up, it looks like that was broken or cut once upon a time. I have two branches growing out of the sides and out, then up, and slightly below those two branches are two more growing out and up on the opposite sides. Should I trim that and how?

Thank you


A from Gabrielle Harden,
USU Forestry Extension Educator (sent 5/27/20) -

One of those lateral branches will eventually replace the central leader that was broken. If the branch to replace it is more lateral than vertical, you may need to assist the process. Select the strongest lateral branch just below where the central leader previously was, then make sure that this selected branch is longer than others. The central leader should typically be at least 15 cm longer than the other branches. Ensure that the previous central leader is pruned back (see fact sheet here about pruning), and if possible, provide a stake for the lateral branch that was chosen to replace the central leader. If the lateral branch is nearly vertical already, a stake isn't really required.
It appears the ideal branch to take over is more lateral than vertical, so a stake would certainly be helpful. Leave it in place for a couple of years (or until the lateral branch takes over as the central leader), but make sure that whatever you use to hold the stake to the tree does not girdle the tree.

I hope this helps

Gabrielle Harden


Q from Deborah, Clearfield, UT (received 5/26/20) -

We have three green vase zelkova trees in our backyard that we planted over 12 years ago. All of the trees have been doing well, but recently one tree has leaves that are changing color- they are no longer a nice green color but a light/pale yellow- almost translucent. Not all of the leaves on the tree have changed, just a few branches worth. Any thoughts on what we need to do to help our tree? Thanks!


A from Gabrielle Harden,
USU Forestry Extension Educator (sent 5/27/20) -

Deborah,

At first glance, my mind goes to iron chlorosis. This is common in our region as our soils have a higher pH and therefore lack iron. However, then I saw the picture of the white spots found on the branch. That appears to be European Elm Scale. The zelkova is part of the Ulmaceae family, same as the elms. Have you started noticing any honeydew on surfaces below the tree such as patio furniture or a parked car?

Scale feeds on the sap found in twigs and leaves. Scale can cause leaf yellowing and early leaf drop. If possible, get in for a closer look to determine how bad the infestation is. Heavy infestations can cause branch dieback. Treatment is possible with horticultural oils or insecticides.

Here are a couple of links that will be useful for you -
https://utahpests.usu.edu/ipm/ornamental-pest-guide/arthropods/scales/european-elm-scale

https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb5350728.pdf

It is important to reduce stress on the tree. This means providing adequate water (trees need to be deeply watered - drip lines and sprinklers typically can not provide deep enough watering).

I hope this helps.

Gabrielle Harden


Q from Anderson, Twin Falls, ID (received 5/23/20) -

I am interested in planting some chestnut trees in Twin Falls, Idaho. I know they need to be in a place with good drainage but I am wondering if there are particular varieties of edible chestnut that may fair better than others.


A from Gabrielle Harden, USU Forestry Extension Educator (sent 5/27/20) -

As you may know, a big issue with chestnut trees is chestnut blight. This decimated the American Chestnut populations years ago. Science has taken us a long way, and some trees have been improved to be resistant. Just move forward knowing that chestnut blight could potentially cause problems at some point. 

Chinese chestnut (Castanea chinensis) would likely do fine. They are highly resistant to chestnut blight. Cold hardiness should not be an issue as Twin Falls is 6b and the Chinese chestnut does well down to zone 4. They also do well in dry, hot climates so there is no need to worry about that. As you know, they need to be planted in pairs or large groups to ensure pollination. Along with well-draining soil, chestnuts prefer acidic soil.

The Northern Nut Growers website has a significant amount of information and tips about growing nut trees - https://nutgrowing.org. They even have a list of chestnut experts you can email with questions - https://nutgrowing.org/research-and-resources/experts/.

Best of luck!

Gabrielle Harden


Q from Merrilee, Salt Lake City, UT (received 5/21/20) -

Should I be treating my white fir and columnar spruce for bark beetles? We have met with two tree care companies and they've each given us detailed information of what they would propose to be done in our yard and it's conflicting. We have over 50 mature trees (firs and maples) - we care tremendously about the trees in our yard!

Thanks so much

Merilee and Doug


A from Ryan Davis, Arthropod Diagnostician, Utah Plant Pest Diagnostic Lab (sent 5/22/20)

Hi Merrilee,

In short, there is no reason to preventatively apply pesticides to your trees unless you have a reason to believe they are in imminent danger. Imminent danger would be:

- spruce trees on surrounding properties have been dying (due to bark beetle (ips) attack)
- fir trees on surrounding properties dying due to bark beetle attack or even balsam woolly adelgid attack (this would be unlikely where you are)
- maples dying nearby (I really doubt this is happening)
- or, your trees are very unhealthy, drought stressed and susceptible to insect and disease pressure

Most issues with spruce and fir in the valleys are due to drought and heat stress (which could ultimately lead to insect attack). Bark beetles that kill fir, do not kill spruce and vice-versa. The beetles that killed all of the trees up in the mountains (lodgepole pine and spruce) are two different beetles (mountain pine beetle and spruce beetle) and neither are likely to come into a residential property in the valley and kill trees. I really have not seen bark beetles killing fir trees in residential areas, though it is a possibility, I suppose. If someone is trying to push insecticide injections for bark beetles I would be very wary. There is very limited evidence that systemics work for bark beetles, and only one (emamectin benzoate: Treeage) has really shown promise.

Good Luck
-Ryan Davis 


Q from Amy (received 5/20/20) -

This is a Kwanzan cherry. What is going on here and how can I help it? This tree is usually a prolific bloomer, but this year it barely bloomed at all and the leaves are sparse. There are new leaf buds on the bare branches that are healthy.

Kwanzan cherry 1
Kwanzan cherry 2

A from Gabrielle Harden, USU Forestry Extension Educator (sent (5/21/20) -

Amy,

It appears that this tree may have a canker. Unfortunately, with its location, there is not much you can do. If cankers occur on branches, the branches can be pruned to remove the canker. Here, the canker is on the bole. Cankers are caused by a variety of fungi, most commonly a fungus called Cytospora, but they can also be caused by bacteria. Your tree appears to have the fungal variety. The sap coming out is a condition referred to as gummosis - typically the result of another condition (cankers, insects, wounds, etc). Cankers are often the result of stressful conditions for a tree. It could have started as a frost crack and the fungi or bacteria got in. Trees are more susceptible when they are stressed or wounded. It is important to provide your tree with the proper environment (enough water, adequate sunlight, nutrients, minimal competition, etc.).

With the tree already being under stress, it is more susceptible to other pests such as insects. Reducing stress is vital to preventing further issues. Keep an eye on this area to make sure there are not insects getting in. If you see exit holes and frass, insects are in your tree and you have an entirely new issue.

To manage this there are some things you could try, but I fear this canker has gone too far. Once cankers are in the bole of the tree, there is little that can be done. 50% - 80% white latex paint mixed with Captan or Topsin OR Surround mixed with lime sulfur painted onto the area. Your best option is to ensure you are giving this tree enough water (drip irrigation often does not water deep enough, a tree needs to be deeply watered - 10 gallons per inch of diameter is a general rule of thumb) and continue to provide ideal living conditions. It is possible that once this tree gets enough water, the wound will start to heal and the tree will be just fine.

Here are a couple of resources that you may find helpful -

I hope this helps.

Gabrielle Harden

Gabrielle Harden


Q from Matthew, Landscaper, Saratoga Springs, UT (received 5/18/20) -

I am a landscaper and have been for 6 years. I have planted plenty of trees in the grass area. I have never put supplemental water like drip or bubblers around trees that are in the grass. I've always just depended on the grass sprinklers to water the trees. Should I add bubblers or drip for the trees even though they are in the grass?

tree

A from Gabrielle Harden, USU Forestry Extension Educator (sent (5/19/20) -

Matthew,

The problem with depending on drip systems, bubblers, and even sprinkler systems to water trees is that trees need significantly more water than those provide.It is very difficult to irrigate trees enough with drip irrigation systems. Large trees, and small trees that will eventually get large, need or will need, a lot of water. Of course, different species have different requirements, and the age of the tree will play in to how much water it needs. A young, recently planted tree in a well draining area will need to be deeply watered at least once a week to promote root growth.

Hope this helps

Gabrielle Harden

Gabrielle Harden


Q from Janet, Bluffdale, UT (received 5/18/20) -

My daughter just planted her yard in Bluffdale. How do you tell if a snowball bush plant is in transplant shock? Just planted four days ago and it looks wilted. Dropping heads of flowers. What can we do for transplant shock?

Do they need to replant it or less water or more sun. It only gets a few hours since the house is north facing.

snowball bush plant

A from Gabrielle Harden, USU Forestry Extension Educator (sent (5/19/20) -

Janet,

The Snowball Bush Viburnum plant can tolerate part sun but it really needs 6 to 8 hours of full sun to thrive. The soil should be kept moist, not wet, and it should be well draining. After planting, it should have been deeply watered, and it should be deeply watered at least once a week, more if the soil is drying out quickly. It is better to do one deep watering a week than several light waterings. Deep watering helps promote root growth. It will not tolerate dry soil.

I would cut off the blooms, as they don't appear to be very happy. New blooms will grow.

With proper watering, it should bounce back. If it is only getting a couple hours of sun, I would consider moving it.

A quick Google search of the plant will bring up lots of care tips.

I hope this helps.

Gabrielle Harden

Gabrielle Harden


Q from Dustin, Sandy, UT (received 5/17/20) -

I have a tree I need help identifying. I think it is a beech, but not sure what type and if it is a columnar. I am also wondering how wide it will get. I was wondering if you could help?

possibly a beech tree

A from Gabrielle Harden, USU Forestry Extension Educator (sent (5/18/20) -

Dustin,

This is a European Beech. It is columnar. The coloration of the leaves make me think it might be the Purple European Beech cultivar. This cultivar has leaves that emerge purple, and then fade to a purple green.

The European beech grows to a height of 50–60 feet and a spread of 35–45 feet at maturity. If it is in fact a Purple European beech, those grow into a wide oval, 70 to 80 feet tall and spreads 50 to 70 feet at maturity.

I hope this helps.

Gabrielle Harden

Gabrielle Harden


Q from Cynthia, Holladay, UT (received 5/15/20) -

I live in Holladay, Utah. I just found that my recently transplanted peach tree (two years ago) is leaking sap badly in several spots. I've read about the borer pest but is that likely the cause this early in the year? We replanted this tree in my yard from an orchard In American Fork that was going to be cut down for development into housing.

peach tree leaking sap 1
peach tree leaking sap 2

A from Gabrielle Harden, USU Forestry Extension Educator (sent (5/18/20) -

Cynthia,

It appears your peach tree has gummosis - prolific oozing of sap. Many stone fruit trees are sensitive to injury, and this can result in sap leaking from the trunk in the spring. This can be caused by different biotic (living) and abiotic (nonliving) factors - Chemicals, insects, disease, growing conditions, or wounding damage.

To help identify which factor is contributing to the gummosis, it is best to rule out the most destructive first. Insects will leave exit holes and frass (similar to sawdust, but very finely ground). If insects are causing the gummosis, the exit holes and frass will be visible beneath the sap. I can not see any in the photos, but I suggest you do an up close inspection to ensure that insects are not to blame here. (If you see something but you're unsure, send a photo)

If you've treated the area around the trunk with a chemical herbicide, this could have made the gummosis worse, as it is easily absorbed through the trunk. It is also important to consider how the tree is being watered. If you have a sprinkler system that is putting water on the trunk, this can lead to damage and eventually gummosis. Make sure the tree is only being watered around the base.

Pathogens can also be to blame. When a tree is stressed from any of the previous reasons, they are more susceptible to disease infection. Fungal gummosis causes blisters and raised lenticels - which cause cankers. The areas around the canker then ooze an amber-colored sap in the spring. Because I am unable to see any evidence of insect damage (again - get a closer look - you will be able to see better in person than I can in a photo), I suspect this tree is infected with the fungus Cytospora.

This fact sheet briefly describes the various pests of peach trees - https://utahpests.usu.edu/uppdl/files-ou/factsheet/peach-pests.pdf

I would also recommend a quick Google search of peach tree cankers.

Unfortunately, once insects or pathogens get into a tree, there is little that can be done.

I hope this helps.

Gabrielle Harden

Gabrielle Harden


Q from Megan, Bountiful, UT (received 5/15/20) -

Can you tell me what type of tree this is? It drops millions of seeds, which pile up in heaps everywhere, sprout like crazy and which I collect by garbage cans full? You can tell I love (not) this tree. Does it have any redeeming qualities, like benefiting my garden soil or providing habitat for a rare species of bird? Thanks!


A from Gabrielle Harden, USU Forestry Extension Educator (sent 5/18/20) -

Megan,

This is a Siberian Elm. They are extremely aggressive - if not properly managed (i.e. removal of seeds), it can become weedy or invasive. They have weak wood and are prone to branch breaks. They are susceptible to insects and diseases. Siberian elms can attract migrant birds, but I don't believe it is home to any rare bird species (not to my knowledge).

I hope this helps. Good luck!


Gabrielle Harden


Q from Paula, Clinton, UT (received 5/14/20) -

I just noticed some strange discoloration of the leaves on my Emperor One Japanese Maple. Wondering if I can send a picture and get some advice. Thank you for your help.


A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 5/15/20) -

Paula,

This looks like frost damage to me, with the damage happening while the leaves were just emerging. The damage then was only to the tissue at the edges of the leaves that had started to grow out, while whatever leaf tissue that was still in the bud or hadn't even been formed yet was protected and came out undamaged. Enough of the good leaf tissue is still there though that it doesn't look too bad and it will be healthy. When it leaves-out next year, it will be fine.

Mike Kuhns


Q from Jim, Midway, UT (received 5/14/20) -

We have quite a few aspen trees that are 25 to 30 years old. I believe the developer planted them because they grow quickly. I've been told they are not good trees for a yard due to typical dying at 25 to 30 years. Some people in my development want to keep them and tell me they will live for 80 years if cared for. We have had half of the trees just die so far.

Are aspens good trees for a yard and should we consider replanting new aspen trees where the old one died? Or are we better off finding a more suitable tree? Any alternative suggestions for Midway? This has become a very divisive issue in my community with half claiming one thing the other have claiming the opposite. I need help finding out what an expert knows that does not have a financial interest in the outcome.

Thank you so much for you help and consideration!

Best,
Jim


A from Gabrielle Harden
, USU Forestry Extension Educator (sent 5/14/20) -

Jim,

Here is a very useful fact sheet we produced regarding aspen - https://forestry.usu.edu/news/utah-forest-facts/aspen-how-to-grow-a-good-tree-in-a-bad-situation.
 
I can understand why there is a battle in your community. Aspen are quite beautiful and grow quickly. On the other hand, they can be extremely invasive. As you may know, aspen can reproduce through suckers - seedlings that form from the roots of the parent tree. These are not stopped by concrete garden barriers or sidewalks. Aspen suckers will pop up all over your yard and garden beds and managing them is not a fun task. They will cross property lines and become a problem for your neighbors (though from the sounds of it, some of them may enjoy that). You can cut the suckers and reduce sprouting by using an herbicide (detailed here - https://forestry.usu.edu/ask-an-expert-new/aspen_rootsprouts) but it weakens the parent tree and the sprouts will still come back.
 
Another issue is that while aspen is native in Utah, it is native at higher elevations. The conditions at our elevation (under 6,000 ft) are not ideal for aspen. It is too hot, too dry, and the soil pH is too high. These conditions will only shorten their life even more, while opening them up to the susceptibility of diseases and insects.
 
I would not recommend planting an aspen in your yard. I would opt for a tree that is better suited to your area. A list of uncommon, but excellent suggestions, can be found here (I highly suggest you browse it over) - https://forestry.usu.edu/news/utah-forest-facts/16-less-common-trees-for-utah-landscapes-diversifying-utahs-community-forests.
If you're looking for shade, you could plant a maple (Norway is very common here), but our high soil pH and lack of iron can cause chlorosis, which often occurs in maples planted here. The Kentucky Coffee Tree would do well in Midway - though the growth is on the slower side. Northern Catalpa would also be a good option - it is fast growing, drought tolerant, suitable for alkaline and clay soils, and attracts hummingbirds with its showy white flowers in the spring.

I hope this helps. Good luck!


Gabrielle Harden


Q from Katie, Bluffdale, UT (received 5/14/20) -

We live in Bluffdale where our soil is very dense clay. We are having trouble with most of our different types of pine trees. We have had several die on us already and we are worried about the ones we still have. They are just turning brown and loosing their needles. Is there anything we can do to help them? Most of the year we use secondary water through a drip system to water them. Thanks for your time and help!


A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 5/14/20) -

Katie,

As soon as you said drip system I knew what at least part of the problem probably was – lack of water. It is very difficult to irrigate trees enough with drip irrigation systems. Large trees, and small trees that will eventually get large, need or will need, a lot of water. A blue or Norway spruce as it gets large eventually will require at least 150 to 200 gallons of water a day. And some tree species are more likely to get attacked and weakened or killed by insects (like bark beetles in spruces) or diseases (like stem canker fungi in cottonwoods and willows) if they are water stressed.

There also could be a related problem – accumulating salt from the secondary water system. I have looked at sick trees in the Bluffdale area before and they had salt accumulating in the soil because the irrigation water in that area has salty water. I think that I was told that salt is a problem if you get irrigation water out of that end of Utah Lake. Salt is not good but when you are irrigating small amounts and not very often the salt will accumulate because you never put on enough water all at once to flush the accumulated salt out of the soil.

Here is a recent description I wrote in an email for someone else about how to water trees:

For any tree it is best to water long enough to get water at least 12” deep, often enough to keep the soil moist between waterings, and over an area broad enough to moisten about 60 cubic feet of soil volume per inch of trunk diameter that your tree should have. The way you do this is to experiment with amounts of water and timing and then see how deep the water goes given that amount and timing using a probe. A probe can be a long screwdriver or a steel rod with a T-handle at least 12” long. You push it into the soil and it readily penetrates moist soil but not dry soil.

Also Deodar cedar, which was one of your selections, is on the edge of being cold hardy in the SLC area. It has a USDA Hardiness rating of 7 to 9 and the SL Valley varies from zone 6 to 7 (see hardiness info at https://forestry.usu.edu/trees-cities-towns/tree-selection/hardiness-zones). However, I have seen enough Deodar cedars doing OK in the valley that I doubt that that is the problem.

I recommend that you have an arborist come by and look at your trees and advise you. A soil and irrigation water salt test would also be good. If you can switch to culinary water occasionally or always that would be better for your entire landscape. At least a few times a season putting on extra water (culinary water if possible) will remove accumulated salt. Also you should look at the fact sheets on planting and other subjects on our website at forestry.usu.edu.


Mike Kuhns
Mike Kuhns

Q from Barbara, Sandy, UT (received 5/10/20) -

My home is located inside a yard area with Siberian elms on all 3 sides with seeds, leaves and trash. Is there any depredation for such a massive problem. One tree has slime flux. Is there any help?

A from Gabrielle Harden, USU Forestry Extension Educator (sent 5/11/20) -

Barbara,

Siberian elms are known to leave an awful mess with their yellow pods covering everything in site. If the seeds become established in the earth, seedlings can sprout that are difficult to eradicate. Seedlings can also sprout from the root systems. Some regions consider them noxious weeds. On the other hand, they are adaptable with our changing climate and provide a good source of shade. If you don't want the mess that these trees are creating, you could consider having them removed. With larger trees, you could attempt to girdle them. This would cause them to die within 1-2 years.
 
Slime flux, while not visually appealing, it typically is not harmful to trees. It occurs in response to a previous wound. When a tree is wounded, bacteria can enter and slime flux can occur. This fact sheet provides some in depth detail about slime flux: https://utahpests.usu.edu/ipm/notes_orn/list-treeshrubs/slime-flux
 
I hope this was helpful.
Good luck.


Gabrielle Harden


Q from Angie, Hyde Park, UT (received 5/8/20) -

I have a couple different varieties of maples that are coming out of dormancy, and for the second year in a row, the tips of the branches have no leaves and appear black/brown. Last year, I assumed it was fireblight and pruned and sprayed a copper fungicide.
What could be ailing them and how should I treat it?

A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 5/12/20) -

Angie,

The photo is blurred, but it appears to be an ‘Autumn Blaze’ maple and if not that, some other maple related to red maples (‘Autumn Blaze’ is a hybrid between red and silver maples). They grow well but get very chlorotic (yellow) in Utah’s high pH soils because the high soil pH limits iron availability. They end up not having enough chlorophyll in their tissues which leads to yellow or almost white leaves that are easily damaged by the sun and often turn brown or black. The most tender tissues are in the tips of the branches, so that is where the damage would be the worst. There is little you can do about iron chlorosis other than choose trees that are well adapted to high soil pH. Silver maple and its hybrids are the worst and red maples are close behind. The main treatment for chlorosis is to add iron chelate (chemicals like sequestrene) to the soil and water it in. However, it takes a lot, it is expensive, and at best it only lasts a year. Acidifying the soil would be a great alternative except lowering soil pH enough to make a difference is not possible.

Go here for more information on iron chlorosis in trees: https://forestry.usu.edu/trees-cities-towns/tree-care/preventing-iron-chlorosis


Mike Kuhns
Mike Kuhns

Q from Will, Draper, UT (received 5/7/20) -

I have a mature long needled pine tree in my back yard. It is losing needles and appears less foliated than normal. It has large pustules of sappy material with what appears to be insect larvae in in several locations on the trunk and branch junctures. I assume it is a beetle infestation of some type.
Can you recommend a treatment and an applicator if it requires a professional license to treat it. The local IFA recommended a soil drench treatment of insecticide, but I feel like an injection treatment might be necessary.


A from Ryan Davis,
Arthropod Diagnostician, Utah Plant Pest Diagnostic Lab (sent 5/8/20) -

Two things about these photos.
 
  1. I am thinking that the brown needles are just old needles that haven't dropped yet. They died just due to the trees physiology and that is very common in the fall: https://forestry.usu.edu/trees-cities-towns/tree-care/pine-losing-needles
  2. The resin masses on the tree are located around pruning wounds and are large. My guess is that these masses are from the sequoia pitch moth (SPM) and not bark beetles (Ips spp.). SPM does not often kill trees (only small diameter trees via girdling) an they are an aesthetic issue. The homeowner could choose to do nothing. We have a good fact sheet on this insect and some cultural/mechanical remedies for them, but there is no recommended insecticide treatment for these at this time. https://utahpests.usu.edu/uppdl/files-ou/factsheet/sequoia-pitch-moth-2016.pdf

Best of luck,

Ryan


Q from Elizabeth, USU Extension Assistant Professor (received 5/7/20) -

I have a resident in Oakley that wants to put in some spruce as a windbreak. The location where he needs the break is very near the line from his concrete septic tank to the septic.

A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 5/8/20) -

Elizabeth,

You can’t keep roots out of such an area long term with physical barriers. If they can get oxygen and water they will be there eventually. A high-quality wrapping of geotextile fabric will keep them out for awhile. Probably the best bet is to use chemicals that kill roots. Rootex is a copper-based chemical that foams when it is put in a pipe in water. It kills roots that it contacts as the foam passes through the pipe.
 
Good luck!

Mike Kuhns
Mike Kuhns

Q from Elizabeth, USU Extension Assistant Professor (received 5/7/20) -

Is there a time of day that trees take up more water or is it continuous?


A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 5/8/20) -

Elizabeth,

Water uptake and loss from plants is highest with high air and leaf temperature, low humidity, high light, and high water availability in the soil. Water uptake on a normal day is therefore highest, all things being equal, in mid to late afternoon. How well the plant deals with each of these factors determines how drought tolerant it is, or how much food (sugar) it makes per amount of water used.
 
Good luck!

Mike Kuhns
Mike Kuhns

Q from Cliff, North Ogden, UT (received 5/4/20) -

Hi, my name is Cliff Huss and I live in North Ogden. I have a 30 year old cottonless Cottonwood that appears to be dying and I would like to know if someone could look at it and tell me if that is the case or if it could be saved. There are about 3 branches on the north side that have leaves on them and there are some fuzzies on the tops of several other branches.The tree is about 30 years old. It started as a cotton-less cottonwood but it started producing cotton maybe 5 years ago. Thank you.


A from Gabrielle Harden, USU Forestry Extension Educator (sent 5/8/20) -
 
Cliff,
 
Unfortunately, this tree will soon be dead. It is almost certainly due to fungal cankers that attack the inner bark and cambium are in the trunk and larger branches, killing everything from that point up. Often times it is cytospora. The fungus attacks trees or parts of trees that are already in stressed conditions. Cytospora girdles the tree and kills everything above the canker. This link provides a bit more information about cytospora - https://utahpests.usu.edu/ipm/ornamental-pest-guide/diseases/cytospora-canker.

I hope this helps.

Gabrielle Harden


Q from Carlton, Salt Lake City, UT (received 5/2/20) -


I have a tannenbaum mugo pine tree planted in our front yard that is about three years old in Salt Lake City. The tree began to yellow/brown last summer and this spring the pine needles are covered in what appears to be pine scale but looks smaller and browner than the photos of pine scale found online. It appears they have a yellow inside when scraped off the needle. The spots are over nearly the entire tree. Is this indeed pine scale and, if so, what is the best treatment of the many available options?


A from Dr. Mike Kuhns,
USU Extension Forester and Professor (sent 5/5/20) -

Carlton,

It appears that this is black pine needle scale. This can be successfully treated using a systemic insecticide. The insecticide is sprayed on the bark of the trunk, where it is taken up through deep bark furrows. It can also be injected into the soil, where it is taken up by the roots. The chemical name is dinotefuran and the common name is Safari.
 
Good luck.

Mike Kuhns
Mike Kuhns

Q from Jon, Syracruse, New York (received 5/1/20) -

Hello,

I live in Syracuse and I planted a Norway Maple in my backyard 3 years ago shortly after we built our home. I'm wondering if I need to (or can, for aesthetics) prune the tree? And if so, how do I do this, what is the best time to do so, etc.?

Thank you,
Jon


A from Gabrielle Harden, USU Forestry Extension Educator (sent 5/1/20) -

Hi Jon,

It is not necessary to prune your tree unless it is unhealthy, has hazardous branches, or needs shaping. If the tree is healthy and has good form (shape), I would refrain from pruning. Should you have the need to prune your maple tree, it is best to do so in winter or early spring when the tree is still dormant. Maples tend to give off a sap when pruned during that time of year, but it is nothing to cause alarm and will stop within a few days. If you're wanting the tree to be more shaped, you certainly could prune, but again, you should wait until winter when the tree is dormant. Where you cut the branch is dependent on what type of pruning you're trying to do. If you want to cut back a leader, you can prune the leader to the point where another branch is, given that the remaining branch is healthy and at least 1/3 the diameter of the branch being removed. If you want to remove a larger branch or lower branches, you must prune to the stem (trunk) of the tree. Pruning causes significant stress to a tree, so you will never want to prune off more than 25% of the trees leaf area.

We have a very useful fact sheet that will walk you through pruning in greater detail - including what tools to use, where to properly cut, etc. I suggest you look it over. https://forestry.usu.edu/news/utah-forest-facts/pruning-landscape-trees-an-overview


I hope this helps.

Gabrielle Harden


Q from Wendy, South Jordan, UT (received 4/30/20) -

I have an Austrian pine that is turning yellow throughout the whole tree green and yellow mixed needles. It is 25 years old. I lost one three years ago, acted same way, had no sap tunnels or burrowing sign or holes in bark. Saw no sign of that on the one we like at before either. What can I do I have many of these same trees on my property?
Wendy Penrose


A from Dr. Mike Kuhns,
USU Extension Forester and Professor (sent 5/5/20) -

Wendy,

I can see from your photos that this tree is quite unhealthy. What is most unhealthy looking is the absence of needles. There are some needles but only the newest ones remain on the tree. There should always be at least 3 years-worth of needles on an evergreen conifer like a pine. The newest needles are near the tips of the branches and the oldest ones are farther back down the canopy. Every year the tree branches elongate from the buds in the spring, needles grow out as the branch grows, and a year’s worth of needles (the ones that are farthest in on the branch) die each fall. Though the tree is an evergreen because it always has green needles on it, the needles are not evergreen.

Your tree has lost most of its needles that are older than one year, and the fact that even many of those needles are brown half way down their length is that much worse. And worse still, what live needle material is on the tree is yellow, not dark green as it should be.

I suspect that there is something wrong that involves the soil and the root system, so it would be good for you to dig around the base of the tree and see what you can find, while avoiding injuring woody roots as much as possible. A good way to do this is to use pressurized air to blast away the soil at the root collar, which is where the trunk meets the soil. However that requires the use of an airknife and a large compressor that I am guessing that you do not have. A slower alternative is to loosen up the soil near the root collar and vacuum it away with a shop vac. What you should look for is woody roots that are growing around the trunk base (girdling roots), a deeply buried root collar caused by planting too deep, or something with the soil itself (too wet, extremely compacted, etc.). If you do this, take some photos and send them to me.

Another thing to look at and to take photos of is branch growth for the past 10 years or so. A tree that is becoming as stressed as this one is will have slowing twig growth, and observing that growth can tell you a lot. To measure this growth you just start at the tip of as healthy a branch as you can find on the tree, then go back along the branch and find the point where the terminal bud was 1 year ago and measure the distance from the tip to that point. The way to find this point is to look for a change in appearance of the twig or branch bark, to look for linear scars that circle the stem where the bud scales were attached to it, and often you will have small twigs that branch off of the bigger branch at that same point. Then go back to where the terminal bud would have been 2 years ago and measure the growth from year 1 to year 2. Do this as far back as you can go. On a pine it is pretty easy to go back 10 years or more, and often you can actually age the tree if you go back to the limb and then the trunk and finally the root collar. There is a good chance that whatever is wrong with the tree has been developing for a long time, and doing this will tell you when the problem started by when the growth started to slow down, how abrupt the change in growth was, and whether it is getting worse recently.

Good luck.
Mike Kuhns
Mike Kuhns


Q from Mike, (received 4/30/20) -

I have a blue spruce approximately 30 feet tall that is losing its color and drying at the top. What could be the problem?


A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 5/1/20) -

Mike,

This tree does not look very healthy, even where the foliage is not turning brown. It has been growing slowly (2-3” a year at the branch tips that are not being shaded by branches and needles higher up, versus 8-12” a year that a healthy spruce should be growing). It looks to me like it was doing well for quite a few years, and then the growth slowed for while – maybe for the last 15 years or so. I base this on the canopy shape (look at the photo with the redbud tree in it) where earlier in its life the tree was growing faster and the canopy was more upright and steep sided, while more recently, shown by the upper part of the canopy, the shape has been flattened, indicating slower growth.

The first and second pictures also look like there are several trees that are planted too close together. They are competing for light, which makes them lose their inside needles and branches. That is a natural thing, but if they are very close together none of them will get enough light. Trees that are too close together will compete for water as well. I think that lack of water is the main thing, though the brown part of the canopy could be a bark beetle attack brought on by water stress.

It won‘t be easy to get to, but the branches or the part of the trunk that are/is turning brown is the place that you would find bark beetles if they are there. There would be insect entry and exit holes through the bark and resin coming out in that area. In the mean time, though, I think that the tree needs more water in the summer and you should consider removing the least healthy trees that are competing the most with others.

Good luck.

Mike Kuhns
Mike Kuhns


Q from Christy, Taylorsville, UT (received 4/29/20)

There's a beautiful tree in my neighborhood in Taylorsville and I don't know what kind it is.
Thanks,

Christy


A from Dr. Mike Kuhns,
USU Extension Forester and Professor (sent 5/6/20) -

Christy,

That tree is a shrubby willow that has been grafted to an upright willow to achieve that somewhat odd form. In addition, the shrubby part is a willow with variegated leaves that are green and white, with some pink as well. It may be a variegated Japanese willow (Salix integra ‘Hakuro Nishiki’).

 
Mike Kuhns
Mike Kuhns

Q from David, Japan (received 4/28/20) -

Can a non-Asian tree species (e.g. an Oak) grow in Asia?

A from Gabrielle Harden, USU Forestry Extension Educator (sent 4/22/20) -

Yes. It really comes down to the growing conditions a species requires. Every species has different growing requirements, and it is important to understand those prior to planting. Things to consider include zone hardiness, soil pH, drainage, water requirements, and sun requirements. Similar to North America, Asia has a large variety of hardiness zones. Japan in particular ranges from Zone 3 in the northern region to 11 b on the south-eastern islands. A majority of oak trees can grow in hardiness zones 4-9, some in zone 3 and the Live Oak up to zone 10. The Bur Oak, for example, is very adaptable. This species can grow in a variety of soils (alkaline, acidic, sandy, clay, moist, well-draining). It can grow in zones 3-8 and prefers full sun. Arborday.org is a useful website that provides growing information for a wide variety of tree species.
 
Whenever you plant a non-native tree, it is important to consider whether or not it is considered invasive. Not all non-native species are invasive, but many are. Invasive trees can out-compete native species and drastically change the landscape. There are actually several oaks that are native to Japan, so you may consider those species first.
 
I hope this helps.


Gabrielle Harden


Q from Ryan Davis, Arthropod Diagnostician, Utah Plant Pest Diagnostic Lab -

There is a housing development to the south of Moab that is experiencing pinyon dieback. I suspect that the mortality is due to infestation from Ips confusus, but my guess is that drought stress is adding to this issue. What are your thoughts on reducing drought stress on pinyon pines to reduce their attractiveness to bark beetles? Would you have specific recommendations for irrigating pinyon pines (frequency, drip type, amount of water, etc.)? They want to keep their trees alive and I have given them many options to accomplish this, but I don't see insecticide applications to all trees every year as a good, sustainable solution. One aspect of an overall program would be to reduce drought stress on the pinyons.


A from Dr. Mike Kuhns,
USU Extension Forester and Professor -

Ryan,

This exact thing happened all over central and southern Utah and throughout the Four Corners area about 15 years ago - https://www.fs.fed.us/rm/pubs_other/rmrs_2005_shaw_j002.pdf. If I had a few valuable pinyons I would consider spraying the trunks or soil applications of something appropriate (dinotefuran?) to ward off the beetles for awhile. But I also would irrigate in the hotter and drier part of the summer and maybe the fall as long as things stay abnormally dry. How much to irrigate is hard to say, but when they irrigate they should apply enough to have the water get down a foot deep or more. They can check how deep it is going by occasionally pushing a probe in in a non-rocky area. It will penetrate easily until it reaches dry soil.

Mike Kuhns
Mike Kuhns


Q from Frank, UT (received 4/27/20) -

I have a tree in my yard that Rocky Mountain Power wants to top or cut limbs in a L shape away from the power line. This tree is over 50 years old and at least 30 feet high. It is a healthy tree, Cone shaped I believe it of the Juniper family. I am afraid they are going to kill it with this technique. Please can you suggest a trim that would satisfy the utility but not harm my tree.

A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 4/27/20) -

Frank,

Any tree that grows within a certain distance of a powerline must be pruned enough to maintain clearance. The clearance increases with higher voltage, with the lines that supply individual homes within neighborhoods needing much lower clearance than others. Yours might need 15 feet of clearance, but even then, they usually try to get more clearance since as soon as it starts growing again it will be too close.

Even though the L-shaped, V-shaped, and one-sided trees are odd looking, this pruning does not harm the tree as long as branches are removed back to the point that they meet another branch big enough to suppress sprouting and promoted healing. Typically that means that the branch that is removed is at least 1/3 of the diameter of the one that stays. The one that remains also needs to be healthy and vigorous.

I do think that it is good to contact the power company and the contractor doing the pruning and to let them know that you care about your tree and that you will keep an eye on the process. However, I think that it will not harm the tree.

Mike Kuhns
Mike Kuhns


Q from Sherri, Salt Lake City, UT (received 4/24/20) -

I live in SLC and have a 20 year honey locust that has been watered with the lawn so it has 5 large superficial roots. Is it possible to cut out those superficial roots and have the tree survive? Maybe cut out one a year to not shock the tree too much?

A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 4/25/20) -

Sherrie, This is a problem for you, but thankfully not for the tree. If you are going to remove roots, you have the right idea — remove 1-2 a year. However, the roots are shallow because they can get what they need best at that level. Water, minerals, and oxygen all are needed by roots and all are most available shallow in the soil. Therefore, this will keep happening. The way to deal with emergent roots is to not try to grow anything like turf under that tree. Mulch the area under the tree where you are finding these roots with wood chips or bark.

Good luck.


Mike Kuhns
Mike Kuhns


Q from Robert Poll, South Jordan, UT (received 4/21/20) -

Would Prairie Horizon Manchurian Alder grow in South Jordan or is it too hot for it in the summer?

A from Gabrielle Harden, USU Forestry Extension Educator (sent 4/22/20) -

Robert,

Prairie Horizon Manchurian Alder is a very adaptable species. It is cold hardy to zone 3, so it can survive our coldest winters. This species is tolerant of everything from full sun to full shade, and both wet and dry conditions. Because of its ability to adapt, I believe it should grow just fine in South Jordan.
 
Best of luck,

Gabrielle Harden


Q from Bruce, Torrey, UT (received 4/6/20) -

I have property near Torrey Utah with many juniper trees. I'm the last couple of years I have had three die starting from the bottom branches up. I've removed them and in all three cases they were smaller trees growing next to healthier larger trees. I have one of the larger trees now having some lower branches bare. I would like to preserve it. Is there anything I can do to preserve it? Also anything I can do to protect other trees from developing the problem?


A from Dr. Mike Kuhns,
USU Extension Forester and Professor (sent 4/7/20) -

Hi Bruce, I know what is removing the green foliage from the lower limbs of your junipers. And I bet that you are losing lots of other plants or portions of plants to the same factor. What you are seeing is the effects of deer feeding after a hard winter. Nearly all of the branches low down on the tree are alive, and they probably add a little new foliage to the bare area each year. However, in most years it would be denuded by spring. Above the height that deer can reach the tree canopy is fairly normal.
 
This would be worse if there are a lot of deer and if they don’t have much to eat in winter. Also it can make it difficult or impossible for small trees to get big, because they have no foliage after a hard winter. Once a tree gets a good part of its canopy above the reach of deer then it will usually do well. The best way to get big trees in such a situation is to surround smaller trees with tubes of welded wire fencing. Just make sure that you want more junipers, given their tendency to burn.

Mike KuhnsMike Kuhns
Q from Rick, Bountiful, UT (received 3/24/20) -

I have some very sickly pine trees. A brief description is as of this year when I began to notice issues, first was the needle loss in a couple of the large trees, 80 to 90% has or is in the process of shedding. Also a couple and now 4 other pines are showing brown/yellowing in the last month. I looked closely and found a spongy feel in the bark of one type of pine, some bore holes in another. USU Forestry was mentioned to me by an alumni that said to get your recommend, he gave me his diagnosis as well.

Again, Thanks!
Rick


A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 3/25/20) -

Rick,

There are a few things going on here. The photo ending in 2305_n.jpg has a nearly dead blue spruce on the left, then a pine (probably an Austrian pine) right of middle, and another blue spruce on the right. That looks OK, though maybe growing fairly slowly. I can’t tell what is going on with the spruce but I would bet that it is either soil (and therefore root) disturbance, and/or water stress. And if it is water stress then bark beetles could be involved. It looks like it has been growing slowly for many years (maybe 10). It would be helpful to know how long ago the tree’s growth slowed down. This can be done by photographing fairly closeup the length of a good-sized branch from tip to trunk, overlapping the photos if you need to so I can see the point on the twig/branch where growth started from each year.

The other problem I see is a nearly dead bristlecone pine in the other two photos. I am guessing that it also is not getting enough water, though it also may have borers/bark beetles. There also is a very small spruce that has been shaded out by other trees.

So send me some more photos and I will see what I can do.

Mike KuhnsMike Kuhns


Q from Luke, Missoula, MT (received 3/16/20) -

I read the article where you discussed the oldest English Walnut in Salt Lake. What else could you tell me about it? It is ‘Champion’ cultivar of English Walnut, correct? I’ll have to look at Salt Lake’s lowest winter temps of the last ten years. I’m in Missoula and am interested in growing some English walnuts. I’ve tried carpathian walnuts which are supposedly able to work in our zone 5a climate. But they didn’t make it. Did it get demolished? I’d like to collect seed from it in the fall.

Best,
Luke


A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 3/23/20) -

Luke,

The walnut you have read about is no particular cultivar. It has been designated the Utah state champion, meaning that it is the largest of its species found so far in Utah, using the measurement criteria of American Forests at https://forestry.usu.edu/tree-identification/hunt-for-big-trees

The tree is located in Ogden, about 30 miles north of Salt Lake City. I think of English walnut (‘Carpathian’ is a supposedly more cold hardy cultivar of English or Persian walnut) as fairly cold hardy. Where I live now (Cache County Utah) is considered a pretty cold place, but there are quite as few of them here, though I mainly notice them not in the lowest parts of Cache Valley, which are colder than the benches or terraces on the edges of the valley.

Though the absolute lowest temperatures that are found in an area are often what sets the limit for plant survival through the winter, often variability in temperatures curing the winter, and especially how common unusually early and late hard frosts are is more limiting for species that are marginally cold hardy in an area. I would guess that you have a lot of variability in winter time temperatures and that you sometimes get very early or very late frosts.


Mike KuhnsMike Kuhns


Q from Kerstin Jones, Master Gardner, Salt Lake County, UT (received 2/27/20) -

I work at a small nursery in West Jordan that has traditionally specialized in hanging pots and premium annuals. Last year they decided to venture into landscaping stock as well and brought in an assortment of trees and shrubs, some of which have overwintered on the lot.

When surveying the stock yesterday we noticed many of the trees are severely rootbound in their pots. My employer asked if I would reach out to someone at extension and ask for some information regarding the process of resizing rootbound stock into larger pots. We recently lost our greenhouse manager and have yet to replace her, thus we are left without someone with this type of expertise.

I am familiar with the process advocated by some extensions (CSU in particular) to cut back the entire circumference of the rootball an inch or so with a sharp spade or saw in order to treat circling roots before planting rootbound trees, but I'm wondering how well those trees would survive if they were put in a larger pot rather than planted right away. Some of the trees also have girdling roots as large as 1.5 inches in diameter. Can those be cut off without losing the tree?
Thank you for your time and help. It is much appreciated,

Kerstin Jones

Photo of circling roots
Photo courtesy of Palm Beach County Extension and UF Laura Sanagorski

A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 3/09/20) -

Kerstin,

Normal practice in dealing with potted trees that have been too long in the pot is simply to repot them in a bigger pot. This will make the resulting plants even more likely to have trunk-girdling roots later in life since there will be circling roots where the first pot was located and a second zone of circling roots that will develop at the second pot. It is not that apparently healthy trees with hidden deformed and defective root systems can’t be grown and sold to unsuspecting customers, and they may even do well after planting for up to 5 or more years. But eventually, when the tree’s trunk grows enough in diameter that it meets the first (or second) zone of circling roots which themselves are growing in diameter, then the circling roots become girdling roots and the tree starts to decline with no apparent reason.

The best thing to do is to sell the plants before they get root bound in the first pot, though you did not say what form the owner bought the trees in – are they bare root liners that are planted in pots or are they already potted? Either way, though, they need to be sold before they get root-bound in the first pot. Of course another way to grow bigger trees from small trees (this is especially good with liners) is to plant bare root trees in the soil in the ground instead of in a pot. Then you dig them with a tree spade in a couple of years. Such trees will be much better quality and healthier, with less chance of developing circling and girdling roots. They will also have the advantage of growing their root systems in soil instead of having them start out developing in soil-less potting material like ground bark or peat moss-based material, which results in more natural root growth and distribution. It also does away with problems that can be caused by interfaces between different root ball materials.

If the nursery wants to repot the trees I like the method you described where you unpot them, cut an inch or so back into the root ball to remove the layer of circling roots that has formed there, and then place them in bigger pots. Still, though, it would be better to not let them get so root bound to begin with (and if you are getting some 1-1/2” diameter roots developing in the original root balls then they are definitely staying too long in the pot(s).
I hope that this helps.

Mike KuhnsMike Kuhns


Q from Kerstin Jones, Master Gardner, Salt Lake County, UT (received 2/27/20) -

How soon do dormant trees need to be watered?

A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 3/09/20) -

Kerstin,

I define dormancy as growth and metabolic or biochemical functions stopping in a plant or a part of a plant even though environmental conditions might allow for it. An example is a branch on a tree as it exists in late fall and through the winter with buds closed tight, no growth occurring (in the branch), sugars moved to where they need to be and turned into starch for storage through the winter, and antifreeze chemicals moved to or made where they are needed. This dormancy is usually caused by the plant sensing that the day length has shortened the required amount for that species to be ready to go dormant. The day length is determined by chemical changes that occur in tissues in the bud scales. These changes are actually caused by a change that happens as day length shortens that results in a change in the ratio of near infrared to far infrared light. When that ratio changes enough the plant goes dormant. Then even though the weather might warm, up a bit in December, the plant will stay dormant and won’t be fooled into coming out of dormancy by the weather changing, but will wait for the near infrared/far infrared ratio to tell it that spring is here.

Roots, on the other hand don’t go dormant because they live in a more protected environment underground. The soil mass prevents quick temperature changes and sudden drying out. Therefore, roots grow whenever the soil is moist and the soil temperature is above about 40F. If the soil is too cold near the soil surface but is warm enough deeper in the soil then roots that are located deeper in the soil will be able to grow. What matters is the soil moisture and temperature at the root tip because the tips are where root growth happens.

So, having said all of that, I also need to point out that more root growth is a good thing for trees. And since root growth occurs only in moist soil, then water to keep the soil moist at any time of year when the soil temperature at some depth will exceed 40F.
I hope that this helps.

Mike Kuhns
Mike Kuhns


Q from Rob, Grand Junction, CO -

Would you happen to know of any contacts (university, city foresters, etc.) from areas that have had more experience working with populations of elm seed bug (Arocatus melanocephalus)?

I know this pest has been coined “only a nuisance”, but the calls from residents continue to come in on a daily basis (feels like I’m getting more ESB calls in Junction than I was getting EAB calls in Denver).

I understand Idaho and Utah infestations are a few years ahead of the infestation on the Western Slope of CO, and I always like to see what ideas / insight others may have to offer (especially those who’ve been dealing with issues longer).

Elm seed bug












A from Ryan Davis,
Arthropod Diagnostician, Utah Plant Pest Diagnostic Lab -

Hi Rob,

Our experience in Utah has been that when ESB were finally starting to get noticed (2014) they were a huge problem. My phone was ringing off the hook like never before for any pest - just like what you described. The high populations seemed to persist for 2-3 years, but now they have seemed to quiet down. Whitney Cranshaw (CSU) mentioned discussing a similar thing with others in the intermountain west. I suspect this will be a big problem at first and then may dissipate over time. Of course, their populations may be cyclic, but we'll just have to see about that.

Concerning management: synthetic pyrethroids applied as a perimeter barrier treatment to a structure is the primary recommendation (including around windows, doors and even eaves, if necessary). Exclusion and vacuuming bugs in the structure is also important, but they are very small and can enter a structure seemingly through ANY hole. I have been recommending that people use white duct tape around their window screens to close that little gap between the screen frame and the window frame. They can easily get in that way and then squeeze between windows. I have personally used Demand CS, a microcencapsulated formulation of Lambda-Cyhalothrin for ESB management and it has worked very well and lasts for at least a month-and-a-half. I imagine that any microcap or wettable powder pyrethroid labeled for use as a perimeter barrier treatment would work well. Demand CS seems to be the leader in that category, however. Demand CS is the only product I know of with a special label for ESB. In Utah only the application site, not the insect, has to be listed on the insecticide label.

FYI: we are not recommending treating trees or removing trees, unless the elms happen to be very isolated. As populations may equilibrate, it may be worth waiting it out a few years to see what happens. I have often wondered if imidacloprid applied in the late fall would allow chemical to arrive in the seeds and leaves in the spring, where these ESB feed while they are young. They also feed on leaves, so imidacloprid would end up there, too. ESB, of course, is not on imidacloprid labels, but certainly soft scales (i.e., European elm scale) is, if you need a labeled target pest on Siberian elm.

Please send more questions if you have them; I am happy to help out.

https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=2788&context=extension_curall

- Ryan Davis


Q from Alex -

I have a tree question that I hope to get help on. I have two large trees in my yard. They seem to have fungal infection starting last year. This year it got particularly worse. One of the trees barely has leaves. I have been using anti-fungi spray called ferti-lome Liquid Systemic Fungicide II. It seemed to help last year and started to help this year. Besides doing this, what else can I do? I am worried that the tree may die this year.

Alex

fungus
fungus
A from Dr. Mike Kuhns,
USU Extension Forester and Professor -

Alex,

Your tree is some sort of a sycamore or planetree (Platanus species). The disease is sycamore anthracnose and it is a fungus that attacks new leaves and twigs in the spring when the weather is cool and moist. Once the weather dries out and gets warm it goes away until next year. As far as I know systemic fungicides do not work for treating this disease, but spray application of fungicides like Bordeaux mixture works well. You normally don’t have to do it every year. Go to the USU fact sheet on anthracnose for details at https://utahpests.usu.edu/ipm/ornamental-pest-guide/diseases/anthracnose. Once the young leaves get infected by the fungus they fall off and the tree(s) put on a new set of leaves.

Mike Kuhns
Mike Kuhns


Q from unknown -

What tree is this?

turkish tree hazelTurkish tree hazel

A from Dr. Mike Kuhns, USU Extension Forester and Professor -

Turkish hazel tree (Corylus colurna). Some trees take many years or even decades to reach sexual maturity, which includes flowering and bearing fruit. Most are grafted, which greatly speeds up the process, but especially when they are grown from seeds it can take a long time. Pinyon pines, for example, can take up to 30 years to bear cones and seeds.

Mike Kuhns
Mike Kuhns


Q from John, West Point, Davis County, UT -

I’m wondering if you would know what’s going on with my Yukon Bell pyracantha shrubs I planted just this spring, I think it was in April. They have been doing really well for the most part but all of the sudden most of them are looking really bad. Let me explain...
The new growth is yellow-green where it has normally been a dark green and it also is getting burned/crunchy.
I water them 3x/week as was recommended by two nurseries. They aren’t getting better and a few of them actually seem worse. (Photos attached). Not sure if it’s my soil or what.

Any info you or anyone else could provide me with would be really helpful since I’m trying to not waste the money I spent on these plants with the intent to grow a hedge on a corner of my property.

yukon bell pyracantha
A from Dr. Mike Kuhns, USU Extension Forester and Professor -

John,

I am guessing iron chlorosis is the issue. Do you know your soil pH? If not you might want to get it tested by USU’s soil testing lab — see more at usual.usu.edu. If your pH is 7.5 or more that is probably the issue. Alternatively look around the neighborhood and see if many other plants are yellow. If so then that would confirm chlorosis. If it is chlorosis you can treat the soil yearly in spring with iron chelate, but it is expensive and you will have to do it forever.

 
Chlorosis will be worse if you have compact soil and/or waterlogged soil, causing a lack of oxygen in the soil. Watering 3X a week seems a bit much to me.
 
Mike Kuhns

Mike Kuhns


Q from Richard, Summit County, UT -

Hello. I hope you don’t mind me sending you these photos of my sick aspen. We’ve had a few trees “die” and then leaf out again with new branches at the point where the main tree died. The new leaves are covered with sticky, but I don’t see aphids. They are planted in clay soil. Do you have any ideas about what the issue is and about treatment.

sick aspen

A from Dr. Mike Kuhns, USU Extension Forester and Professor -

Richard,

Aspens have lots of problems, mostly because they do not put any energy into protecting themselves. Your trees appear to have poplar borers in them, which weakens and kills branches and trunks. The first picture looks like iron chlorosis, which is caused mainly by high soil pH. Stickiness would most likely be related to aphids, but stick material oozing from the trunk could be from the borer exit and entrance holes, but also possibly from stem canker, a fungal disease.

You might want to read this fact sheet: https://forestry.usu.edu/files-ou/aspen-how-to-grow-a-good-tree-in-a-bad-situation.pdf.

There really are no practical treatments for aspens because most of the problems they have are not readily treatable. For example, you can’t keep aspens from getting stem cankers and those are very serious problems for aspens. You can have trees sprayed with insecticide to coat the bark to discourage borer entry, but success is hit and miss and it can be quite expensive, plus you would have to do it every year or two. Also such sprays have no effect on borers already in the trees. Chlorosis is treatable by adding iron chelates to the soil, but again it would be fairly expensive and would have to be done every year. Actually the chlorotic leaves you send a picture of are likely chlorotic not due to the soil pH, but I suspect that branch or tree was very stressed by other problems. Irrigating is a good treatment, since most of aspens’ problems are made worse by water stress, but usually large scale irrigation is not practical and it won’t help the already heavily damaged trees. The best treatment is to cut down the oldest trees with the most problems, which will encourage sprouting from the roots. The new sprouts are much more vigorous than the old trees. You can retain the healthier of the big trees, then you can thin the sprouts. The factsheet I cited (above) describes this process.

Mike Kuhns

kuhns


Q from Alex -

There are root like structures coming out of the ground in my yard. Do you know if they are normal or if they need treatment? They are making the lawn look weird. There is a large aspen tree nearby. Thanks a lot!

Alex

A from Dr. Mike Kuhns, USU Extension Forester and Professor -

Alex,

As you know, aspens put out sprouts along their roots that have a stem above ground and roots below. The resulting plant is clonally produced, so it is genetically identical to the original plant. Regular mowing will keep these sprouts from growing and forming new trees. However, stems will try to form at certain spots along the roots, and will attempt to grow over and over, forming a zone of disorganized growth at the soil surface that becomes woody and that gets larger over time. You can get them out by pushing a sharp spade into the ground all the way around the growth and then cut any final roots that are going down by using the spade as a lever.

Unfortunately, though this will remove the selected woody growths, the cutting of the roots will actually encourage additional sprouting along the roots that are cut. It actually causes the creation of separate trees, each of which will sprout. You can reduce the sprouting by using triclopyr herbicide (i.e. Ortho Brush-B-Gone or similar) or glyphosate (e.g. Roundup or similar). To avoid killing the grass near the growth, you should use a paint brush instead of spraying, applying the herbicide to all of the cut surfaces while they are still fresh (within hours is best for uptake). Doing this only makes sense though if you intend to remove the parent tree, since if you are careful to treat every cut surface there is a good chance that you will greatly weaken the parent tree. That is what I recommend doing, since the sprouts will keep on coming as long as that tree is alive. If you remove the tree you should also treat the stump with triclopyr right away. Also, though treating the stump and cut roots will weaken the remaining roots, you will need to go around your yard and your neighbors’ properties and cut any sprouts that have been left to grow and treat those stems. You need to do this quickly whenever a sprout forms. If you let one grow and get leaves on it, you will have the process starting all over again.

Good luck.
Mike Kuhns
kuhns


Q from Joan -

I have three trees in my yard, a maple, a red bud and a honey locust (I think). The trees appear healthy but the people who do my lawn care want to sell me a package of at least 4 treatments, nutrients, oils, etc. Do I need to purchase a preventative tree care plan for healthy non-fruit trees? Also, could you let me know what I should look for in an arborist for trimming? Any suggestions? I would also like information on the lunch webinar series. I don’t know much about tree care, or gardening for that matter, and I would like to learn more. Thanks.
-Joan

 

A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 6/07/18) -

Joan,

The number one thing that all trees need is adequate water. Of the species you mention, the honeylocust and the redbud are fairly drought hardy and the maple depends on what species of maple it is. Trees rarely need fertilizer (nutrients) beyond what they can get from normal Utah soil. I have no knowledge of how you could help a tree by adding oils, other than horticultural oils that are used sometimes to smother insects. I would keep my money in my pocket.


If your trees need pruning you can do it yourself (see https://forestry.usu.edu/files-ou/pruning-landscape-trees-an-overview.pdf), or you can hire someone, preferably an ISA Certified Arborist (not a licensed arborist – that just means they have a business license). You can get webinar info at our webinars page.

Mike Kuhns

Mike Kuhns


Q from Maryanne A, Summit County, UT -

Hello, my husband and I live in on the Wanship/Hoytsville line, about 15 minutes from Kimball Junction and Park City. We have several Scotch Pine trees which are between 50 and 60 years of age, beautiful trees in our front yard. Last fall we noticed the last tree in the row was losing needles, and the tree branches were turning brown. Most alarmingly, the upper part of the trunk began to lose its bark. I called the county agent and he suggested that we soak the tree root ball well just before the ground froze, which we did. This spring we lost the tree. We fear that it is bark beetle. We've taken it out, but can now see the beginnings of loss of bark in the upper part of two more trees. Is there anything we can do to save these beautiful threes? Attached is a picture of one of the upper branches of the tree that went entirely brown and which we cut down. Does this look like the awful work of bark beetles? If there is anything I can treat the upper bark with to kill or halt the beetles, I will do it! Thank you for any help!

Best

Maryanne A.

porcupine damage
porcupine damage

A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 5/11/18) -

Maryanne,

This doesn't look quite right to be due to bark beetle feeding. It looks more like what you would get from an animal scraping the bark and cambium with its teeth. Of course if that were to happen the bark would come off as the feeding was occurring. If bark beetles attack a tree they make an entry hole, tunnel within the inner bark in a predictable pattern that varies by the type of beetle, they lay eggs in their tunnels, the eggs hatch and the young larvae make tunnels that also have a predictable pattern and are smaller in diameter than the adults' tunnels. Eventually they mature and tunnel out through the bark leaving an exit hole. The tunneling of many attacking insects eventually weakens and then kills the tree, but the bark does not come off until that part of the tree is dead. What I am seeing on this tree does not look like bark beetle tunnels. It looks more like the scraping of teeth.

Animals (non-insects) that scrape off bark to feed include porcupines, squirrels, deer, elk, horses, rabbits, mice, and voles. It might seem that you would notice a porcupine feeding, but they mainly feed at night, so you might not. You also might not notice squirrels as they were feeding, and rabbits, mice, voles, and large ungulates (deer and elk) would not be able to reach that far up.
 

If I had to guess I would say that it is bark stripping and not insect damage, and that it is porcupines rather than squirrels because the tooth marks look too big to be from squirrels. To see what their feeding looks like search Google for "porcupine bark feeding" and click on the Images button.

 

It will be difficult to control porcupine damage. It is probably not legal to trap them or shoot them, though your UDWR local office might have suggestions. Your area is covered by the UDWR office in Ogden, phone number (801) 476-2740. If you search the web for "porcupine control" most of the suggestions focus on live trapping. There is a good article at http://icwdm.org/handbook/rodents/Porcupines.asp.

 

Mike Kuhns

Mike Kuhns


Q from Freddy W. -

Good afternoon,

I'm not sure if you're the proper person to contact, but I had a question. I found this in the Coral Pink Sand Dunes Area and wasn't sure what it was. It's about 3 inches long. We believe it's a type of fungus and people have suggested it's a magnolia. I'm not native to Utah or the Kanab area so I'm not sure if magnolia's grow down there. If you can help identify it or direct me to someone who could I'd be very grateful.

Thank you so much,
Freddy W.

ask an expert

 

A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 4/16/18) -

Freddy,

It is not a magnolia. There are planted magnolias in Utah but none in the wild. I believe that it is the beginning of a witches broom or something like that. A witches broom is simply an area of abnormal growth that forms on a woody plant and leads to a proliferation of growth in one area. It will tend to grow in that abnormal state year after year, which can cause the shoot that it is growing from to die due to disruption of the vascular system. That may have happened here. Witches brooms and other abnormal growth can form as a reaction to a virus or another pathogen or for no apparent reason, but all likely happen due to a genetic mutation. Burls on tree trunks are another form of such a mutation. Sometimes the shoot grows in a flattened form which is called fasciation.

These growths are essentially plant cancers. They will continue to grow until they can no longer be supported by the plant they are attached to, and then they will break off or they will lose their source of water and other materials they need to survive as they disrupt the vascular system. Generally I don’t think that they are contagious, and if you prune them off below their point of attachment they will die and will not come back, at least on that shoot.

These types of growths happen on many different types of plants and on a particular plant they can happen in association with different parts of the plants, but usually are associated with the formation of vegetative or reproductive buds. This one looks like it could be either of those. You would have to pick it apart and look for reproductive structures to tell which it is. If you had more of the plant farther down where it is growing normally I could tell you what plant it is. It looks like it would be from an angiosperm, not as gymnosperm. It could be from a willow.

Mike Kuhns

Mike Kuhns


Q from Sharon, Spokane, WA -

Is there anything known about the “tipping point” or ways to predict native trees decline due to drought stress? Most of our native trees and plants are drought tolerant, but in recent years we have had longer periods of no precipitation, high temperatures, big fire seasons, and have been seeing more symptoms of drought stress and other insect/disease problems combining to cause tree death. This is in native forests and rural situations. ( inland northwest- Montana, Idaho eastern Washington. Primarily ponderosa pine, but some other species like doug fir and cedar also).

Sharon

A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 11/29/17)-

Sharon,

There is a tipping point, but it would be different for each species or forest type and what you would measure to indicate whether this point has been reached would vary. If the trees are coniferous evergreens then the best indicator may be how many years worth of needles are on the tree. Severely stressed trees will often lose last year’s needles before the next growing season is over. Also stem (trunk) diameter growth is a good measure of stress. Slow growth is a sign of stress. Finally, susceptibility to insect attack is a good indicator of stress.

Mike Kuhns

Mike Kuhns


Q from Tom, Cottonwood Heights, UT -

I live in Cottonwood Heights but am currently visiting friends in the southwest of France, in Toulouse. Here is a question you have probably never had before! In the north of Spain, in the Basque region, they make a walking stick from a wood Neflier (makhila is the generic name for the walking stick). Is there any equivalent of Neflier in the US?

Thanks for your help

-Tom

A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 10/3/17) -

Tom,

Yes. Neflier is a French name for the genus Crataegus or hawthorn. The Spanish name is Espino. Utah has one native hawthorn – black hawthorn or Crataegus douglasii. I see it all over the place at fairly low elevations where there is some water. It is a muiltistemmed tree or a dense shrub, but some species of hawthorns are tree-like, and many of these are planted in Utah. To learn more about hawthorns go to our Tree Browser website at www.treebrowser.org.

Mike Kuhns

Mike Kuhns


Q from Judy -
A cut aspen tree, with the stump still in the ground, is sending out a huge amount of shoots. Can anything be done to kill the stump, outside of removing it? Can the shoots be killed with some product? Help!

-Judy

A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 7/7/17) -

Judy,

Not really. Just cut it down and spray triclopyr (e.g. Ortho Brush-B-Gone or Poison-ivy Killer) or glyphosate (i.e. Roundup) on the stump surface (it is better if the stump is freshly cut), and cut off any sprouts and treat their cut surfaces too. It may take several rounds of this until everything is dead.

Mike Kuhns

Dr. Mike Kuhns


Q from unknown -

I have a Kentucky Coffee tree in my landscape. It was healthy last year, but this spring just as the leaves were emerging, it was hit by a frost (about 30 degrees F) which killed the newly emerging leaves. A few weeks later new buds had formed but as the leaves emerged they are deformed, almost looking like epinasty from 2 4 D (but no herbicides have been used and the tree branches as 6+ feet above the ground). All leaves are affected. All the information I find on the web indicates that the Kentucky coffee tree is rarely affected by pest or disease, but something is obviously wrong. I have included 2 photos of leaves. Do you have any ideas what is wrong?

Kentucky Coffee Tree 1Kentucky Coffee Tree 2

A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 6/29/17) -

John,

I thought this was going to be a case of deformation due to frost damage of tissues still in the buds, but after looking at the pictures, I don’t think so. For one thing, the type of damage that frost causes usually does not include twisting like this. It is more small holes and bumps. Also it doesn’t make sense since new leaves produced after the original leaves were killed would be from tissues produced after the frost. So I am still thinking herbicide. 2,4-D can drift quite a bit, especially on warm days when it volatilizes. The amine form is the most common and is not as bad as the esters (there are low and high vol esters).

Some plants develop cancer-like growths on some of their tissues and these growths often involve flattening and twisting. Though this is not completely understood, it appears to involve genetic changes in the tissue in certain areas on the plant, and pruning off those areas gets rid of the abnormal tissue in that area. These genetic changes seem to be triggered by viruses, maybe bacteria and fungi, certain insects (forming galls), etc. I don’t know if frost damage could trigger this kind of thing. There is a good article on this in the NY Times at www.nytimes.com/2015/07/28/science/cellular-cheaters-give-rise-to-cancer.html. I have attached a picture of one type of such growth called fasciation, that involves flattening of branches. This one is on a juniper here on campus. I also attached a photo of some frost damage on a maple.

Juniper

FrostI recommend that you watch it and see what happens. It won’t spread to other plants and it may go away. There is nothing you can do about it, so you might as well let it go for awhile. If you do, please keep me informed.

Mike Kuhns

Mike Kuhns


Q from unknown -

I planted the Bur in March and have been excited to see it leaf out. I have noticed that a good number of the leaves aren't the typical dark green that I've seen, and am attributing this to stress. That being said, the leaves are a mixture of light green to yellow/bronze. The veins themselves are still green and the leaves don't appear to be wilting so far. I've also read that this could be a sign of over or under watering the tree. I've attached a photo to better highlight what I am seeing. Any help you could offer to get this tree in good shape would be appreciated.

Bur Oak

A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 5/19/17) -

The leaves look perfect for this time of year. Many plant leaves have some red in them as they emerge, but before they mature. The chlorophyll that will absorb sunlight and use that energy (along with CO2 and water) to make food through photosynthesis is not fully mature at first, and the sun would bleach the chlorophyll without some protection. The red pigment is there to absorb that light and protect the chlorophyll until it can absorb light on its own and use the energy. Some trees retain the red pigment and are more-or-less red all summer, while with others it fades and the leaves end up pure green. Your bur oak will be the latter. In a cool, prolonged spring like we are having this year, the red may hang around longer since the development of the chlorophyll is delayed.

Mike Kuhns

Mike Kuhns


Q from unknown (full conversation) -

When is the best time of year to plant trees?

A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 5/9/17) -

Trees are best planted when they are still dormant with tight, unopened buds in the early to mid-spring after the soil has thawed. Cool temperatures and good soil moisture in the spring help trees get established. Fall planting also works well for many species, though watering is critical if the fall is dry. Summer planting of B&B (balled-and-burlapped) and container plants can be successful, though hot temperatures, dry conditions, and non-dormant trees makes good care especially important and survival less sure. Bare root trees should only be planted in spring while still dormant.

Q - Of those types of trees, which is best?

A - Landscape trees and shrubs can be obtained in four basic types: balled and burlapped (B&B), container/potted, bare-root, and tree-spaded. Each type has advantages and disadvantages and none is ideal for all situations. Bare-root will give the tree the most naturally formed root system and they are less expensive, but they are not commonly available from nurseries. B&B trees are good because they have been grown for several years in soil and are more likely than potted trees to have a well-distributed root ball. Potted or containerized trees are the worst, with it much more likely that the tree will develop root system problems like girdling roots and buried root collars. Spaded trees are good but may not be available.

Q - How large does the root ball need to be?

A: With all four types you need to have an adequate root system – a good rule-of-thumb is that the root system, root ball, or container diameter or spread should be 10 inches to 12 inches for every inch of stem caliper (diameter at ground-line just above any basal swell). Therefore, a 3-inch caliper tree should have a 30 inch to 36 inch wide root ball as a minimum. Root ball depth is not as critical as width but should be larger for larger trees.

Mike Kuhns

Mike Kuhns


Q from unknown -

We have cut down a maple, sycamore and ash tree that were growing in our yard and roots had spread on the surface causing the grass to die. How far down do we need to remove the roots so grass can grow?

A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 4/18/17) -

The roots did not kill the grass. Shade from the tree did, along with competition from the tree for water and space to grow. Just remove the stump and roots down a few inches so you can put some soil down so the grass roots have soil to grow in.

Mike Kuhns

Mike Kuhns


 

Q from unknown -

Is the blue spruce on my property at risk for bark beetle infestation? I go every year to chop down beetle killed trees in the Uintas, (pond pine, white fir), I bring it home, and use it for firewood. I have a blue spruce that I'm concerned may become infected.

A from Dr. Darren McAvoy, USU Extension Forester and Professor (sent 3/7/17) -

You are only putting your spruce at risk if you bring spruce logs down to your property; beetles are species specific. Bringing ponderosa and white fir will not threaten the spruce. Hope this helps.

Darren McAvoy

Darren McAvoy


Q from unknown, Grantsville, UT -

Hi, we live in Grantsville out past Tooele and we were wondering if it is too early to prune our Peach and apple trees. Could you help us on this?

A from Brent Black, USU Extension Fruit Specialist and Professor (sent 3/7/17) -

It is not too early to prune apples, and probably not too early for peach. Because pruning can result in a slight loss of cold hardiness in the remaining branches, it is generally recommended that you don’t prune until the risk of severe cold has passed. Many commercial growers are now pruning peaches, but also watching the weather. If there are extreme cold temperatures (single digits) in the forecast, then stop pruning until the cold weather has passed.

Brent Black

Brent Black


Q from unknown, Delta, UT -

I recently purchased a lot and built a house in Delta, UT. The soil here is very alkaline and I am trying to come up with some sort of plan as to how I will be able to get some trees to grow. I've heard that green ash can do well in this environment but I'm having some difficulty in finding any good info on what and how to plant. Please, if you have any suggestions or could even point me towards some literature on this topic I would be very grateful.

Thank you for your time

A from Grant Cardon, USU Extension Soils Specialist and Professor -

Green Ash does well in high pH soils in Utah. Planting really is nothing out of the normal, make sure that the hole you plant in is 2 to 3 times larger than the root ball and mix the excavated soil with a good compost to enhance the organic matter content of the repacked soil. This will improve the soil structure over time around the roots and the tree should do well. If planted in with a lawn, the regular fertilization of the lawn will provide sufficient nutrition to the tree as well. Be sure not to cover the crown area of the tree (the point at which the shoot and root join). This can cause rotting of the bark above the crown and the tree will be susceptible to fungal and bacterial disease.

If you are interested in other trees that can tolerate alkaline conditions and want to preview other features such as fall color, spring bloom, decorative bark and other desirable features you can consult the on-line Utah Tree Browser put together by our Extension Urban Forestry group. The browser can be found at:

http://treebrowser.org/

One piece of education and advice. Utah soils are alkaline because of the large quantity of Calcium Carbonate (or lime) that they contain naturally. Utah soils can contain anywhere from 15 to 40+ % lime by weight. This lime is a very reactive buffer against pH change and consumes large quantities of acid as it dissolves. One would have to dissolve ALL the lime in the soil before pH can be lowered. In practical terms, this is impossible given the scale of the requirement for acid to accomplish this. One percent by weight of an acre 12 inches deep is 40,000 lbs or 20 tons. Utah soils therefore contain 15-40 times 20 tons of lime in the top foot of an acre of land. So, you can see the problem of scale we are up against. Even our irrigation water contains large quantities of dissolved lime (hence the nice hard water deposits on our faucets and drinking glasses and our windows after the sprinkler wets them!). So, there is just too much pH buffer in our systems to ever try to adjust pH. Better to select plants that are tolerant of alkaline conditions.

Hope that helps.

Grant Cardon

 

Grant Cardon


Q from Mario Medici, Tuxedo, NY -

I’m a hiker (and hike leader) and recently came across a pine tree that I can’t identify. It is located in Sterling Forest State Park, Tuxedo NY, and is one of its kind that I have found. It has a dark green, almost blue, glossy, thick, 5-6 inch needle, with three needles to a bundle (fascicle). I know its not a white pine (there are lots of them and they have 5 needles to a bundle) and my research seems to believe its a Pinus Ponderosa or Pinus Jeffery (pine), neither of which are native to this area and are predominately in CA and the far west region of the USA.

Could it be someone planted it? If it helps, the tree is near Sterling Lake, once a mining area for magnetite.

This is driving me crazy!! Can you help?

-Mario Medici

A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 10/10/16) -

Actually, that is a better description of Austrian pine (Pinus nigra). They have needles in 3s (ponderosa is in 2s and 3s), and 5-6" long needles (ponderosa needles are longer). If you have cones, ponderosa has sharp prickles on the tip of each scale. Austrian has a bump, but no prickle. And mature buds on an Austrian pine are white, while they are reddish-brown on ponderosa.

Mike Kuhns

Mike Kuhns


Q from Gene Tabish, Murray, UT -

I have an Elm tree that is dripping a clear liquid on my lawn. The areas of the lawn affected by the liquid have been killed. Do you have any suggestions on how to remedy this?

Thank you,

Gene Tabish

A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 10/2/16) -

Gene, the only thing that might do this is bacterial slime flux that oozes out of wounds in elms, willows, and some other trees. Normally the waste from this disease runs down the trunk from old pruning wounds and eventually kills grass. I haven't seen this in the form of dripping material, but I suppose it could happen.

Regardless, there is nothing you can do about the disease, and it doesn't harm the tree much. If you mulch under the tree there won't be any grass to kill.

Mike Kuhns

Mike Kuhns


Q from unknown, Blanding, UT, San Juan County -

We planted 52 new 4-6 ft. trees in March 2016. We have been watering them 3 times a week (about 10 gallons per watering). Now that it has cooled off and turning fall, how often do they need watered?

 

A from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 9/12/16) -

Roots will grow as long as the soil they are in is moist and while the soil temperature is above 40 degrees F. And it is good for roots to keep growing because it will speed the trees' recovery from transplant shock. But once it cools off enough then little water will be transpired from vegetation and it won't take much to keep the soil moist. So as long as it stays cool you can back off to maybe once every couple of weeks, or don't water at all if you get significant precipitation. A good way to tell how deep you are watering if the soil is not too rocky is to use a probe like a long screwdriver or a steel rod welded to a handle to form a tee. It will penetrate moist soil and will stop when it reaches dry soil. You would like to water enough that the soil is moist down to at least a foot.

Mike Kuhns

Mike Kuhns


Q from unknown -

I have an ornamental weeping cherry, and I believe it was grafted. I would like to prune it so it can retain it's weeping form. What do you suggest?

A from Dr. Mike Kuhns, USU Extension Forester and Professor -

With grafted plants it is important that you know what is the rootstock and what is the top. Often plants are grafted just above ground with one plant that has it's top completely removed, the rootstock, and one or more plants that have no roots but are desired for traits that their tops have. In the case of almost any trees that have a weeping top and an upright stem, you actually have 3 or more plants -- the rootstock, the upright stem (which may be a part of the rootstock), and the weeping part. And on some ornamental cherries there may be several top branches attached to the top of the upright stem.

Any of the parts of such a plant may form buds and those buds can grow new top material, but if you want to retain the grafted form as it was meant to be, you have to prune off such shoots. In some cases, like with twisted forms, the twisted top may actually grow slower, and if a straight shoots come off of the rootstock, they may eventually shade out the twisted parts.

I hope that this helps.

Mike Kuhns

Mike Kuhns