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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.

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.