The most overlooked problem in Idaho is how clay soil affects our trees. Trees roots need macropores or "air space" or you literally suffocate them. Clay is not "bad" soil, it's just too compact and needs organic matter to create that air space.
Back East the Arborist effectively fix this with what is called an Air Spade; however Idaho has been slow to get this critical aeration tool working on our trees. Over eighty percent of the tree evaluations I am called out on have soil compaction that is creating the symptoms. Over compacted soil slowly suffocating a tree, and making it unhealthy, invites in other disease and pests that target sick plants. An uninformed Pest Control person will advise pesticides but what we really need to do is improve the environment the tree is in and make it healthy so it can fight off those issues.
So what do we do?
It is a simple process of using high-pressure air to break apart that soil without damaging the roots as shown in these two videos.
Part One showing the trenches for Air Spade Repair
Part Two Showing the Air Spade in Action
If you want healthy trees in heavy clay; you have to fix the problem. Fall is an ideal time on dormant decidua trees. Cost usually starts around $475 to get the equipment, people and materials on the first tree but then subsequent trees are $165 clear down to $50 for smaller trees.