Trees died over winter
I have 3 black walnut and 2 ash trees which all died this past winter after a healthy season last year. Three other trees in the same area are showing little leaf with only 1-2 branches leafed out. These are mature trees in proximity to each other. An arborist did not see evidence of disease or bug infestation and thought it was related to the soil. The trees have been here over 25 years; I say that time frame because that was when the lot was developed. They may have been here longer because the property had been a tree farm before development. (we've been in the house for 3 years) Other trees on the property seem to be unaffected. The lot is wedge shaped with this yard on the east facing behind the house. The affected trees are all directly behind the center of the house. We will have to have them removed, but I'd like to understand a cause in order to go forward with any replacement planting. Do you do soil testing?
Thanks for your question and sorry to hear about your trees. The U of M does have a soil testing service. You can find out more about it and how to order different types of tests here:
Tests will generally tell you about the levels of different minerals in the soil, pH level, texture, etc.
Let us know what you find or if you have follow-up questions.