Maintenance of a thinning old Oak tree
I have cared for this Oak tree for the last thirty six years that I have lived in Silver Spring, It has been healthy and at times, pruned to eliminate the small dead branches. Just this summer, I have noticed that there seems to be a thinning of the canopy of leaves. I would like to see if there is someone who can visit and determine what steps to take to feed or care for the tree this year and see if this can provide any treatment or food that will allow the tree to come back next year more healthy.
We do not make home visits to evaluate trees. We encourage you to contact a certified arborist who can do this type of consultation. You can find a certified arborist near you using the "find an arborist" search on the website of the International Society of Arboriculture. http://www.treesaregood.org/
Mature trees generally don't need fertilizer (especially if they are adjacent to a lawn that is fertilized) and fertilizer applications should be based on soil test results if a nutrient deficiency is noted.
A certified arborist will have the tools and know-how to check for diseases/pests or abiotic (non-pathogenic) issues and can provide recommendations for you.