Ask An Expert

     

     

    Q: 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: 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

    April 18, 2017

    Mike Kuhns


     

    Q: 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: It is definitely not too early to prune apples, and probably not too early for peach.  Because pruning can result in a slight loss of cold hardiness sin 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 is extreme cold temperatures (single digits) in the forecast, then stop pruning until the cold weather has passed.

    Mike Kuhns
    April 07, 2017

    Mike Kuhns

     


    Q: I just took a call from Edward who is interested in knowing whether the blue spruce on his property is at risk for bark beetle infestation. He goes every year to chop down beetle killed trees in the Uintas, (pond pine, white fir), brings it home, and uses it for firewood. He has a blue spruce that he's concerned may become infected. Since this is not my area of expertise, I'm asking you to please respond.

    A: 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
    March 07, 2017

    Darren McAvoy


    Q: 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: 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
    March 07, 2017

    Brent Black

     


    Q: Megan, 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: 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

    Professor and Extension Soils Specialist

    Utah State University

    Grant Cardon


    Q: 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: 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
    October 10, 2016

    Mike Kuhns


    Q: 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

    Murray, Utah

    A: 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
    October 02, 2016

    Mike Kuhns

     


    Q: We live in Blanding, Utah and 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?

    San Juan County Utah
     

    A: 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
    September 12, 2016

    Mike Kuhns


     

    Q: 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: 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, Professor, Extension Forestry Specialist

    Mike Kuhns