Maple Tree and Verticillium Wilt (VW)
Hi. Based on the symptoms (last year and this one) I believe my maple is infected with VW. One half the tree is dropping its leaves and has been for about 2 weeks. It did this last year too. In the last 8 - 10 years the maples in my development have been dying slowly. Didn't included a pic since it's just leaves (which look healthy) on the ground. From my online research this is soil borne and can be treated. However recommendations include confirmation from a licensed arborist. Is there something else this could possibly be? Is there a list of local arborists (Ellicott City area) that you can share? Thanks for your help.
Verticillium is over-diagnosed in our landscapes. The symptoms that you describe are not typical of Verticillium Wilt, which usually shows up as scorching and drying of leaves that tend to hang on.
There are multiple other things that could be going on. The fact that it is on one side suggests a root disruption of some sort. Any digging, trenching or vehicle traffic on that side?
Maple trees planted in neighborhoods often suffer stress from what we'd term 'abiotic' or environmental issues that include being planted too deeply, being mulched too deeply (should only be 2-3 inches and not touching the bark. We often see 'mulch volcanoes, which are bad), lack of water etc.
Maples are also prone to girdling roots, which can circle around the base of the trunk, eventually cutting off the vascular flow.
All of those things can slowly kill a tree over time.
See here: https://extension.umd.edu/hgic/trees-and-shrubs/trees-and-shrubs-cultural-and-environmental-problems
An on-site evaluation with a Certified Arborist, credentialed by the International Society of Arboriculture (ISA) is a good idea. Big tree companies like Mead Trees and Bartlett etc. often have one on staff.
You can also search for one at www.treesaregood.org