Trees and shrubs dying on our two acre lot along the Loch Raven Reservoir
Within the last eight years we have lost at least ten trees to what appears to be a mold or fungus. Many times the problem is not noticeable on the outside of the tree. The tree dies and inside the branches it looks like sawdust on some. Others have something growing on the branches of the trees. We are losing much of our natural forest on the property and it looks like many more trees are dying. The problem seems to be affecting all of our trees and not just one species. It also seems to be affecting some of the shrubs. Trees on our neighbors properties are also being affected as well as down the road along the reservoir. I've attached pictures and was wondering if this is a natural phenomenon or a serious concern for our woods.
The photo in the bottom left corner of your 1st photo , along with the 3rd photo, show a blueish-green patch. These patches are lichen, part algae/part fungus. They do not harm trees, but can be a signal that something else is stressing the tree. Here is info: http://extension.umd.edu/hgic/expert-plant-picks-lichen
The other photos show a variety of decomposition fungi. These fungi break down dead wood, which means that the wood is already dead. The fungi were not the cause of the wood dying.
Trees are always dying and new tree seedlings should be coming along to replace them. Because of heavy deer browsing, few tree seedlings survive to replace downed trees. You may want to contact your county and state representative about increased deer control. Deer overpopulation is not merely a nuisance. It is destroying our parks and natural areas and making them uninhabitable for all the other wildlife.
Changing environment can also stress trees. Drought, especially, a few years in a row, can push trees into decline that may have been in a marginal situation to begin with. For instance, a dogwood naturally grows in part shade in a woods understory. It may grow in a baking front yard and compacted soil for a few years, but eventually, as it gets bigger and needs more water and nutrients, it will not be able to survive.
Would trimming the branches with the algae and fungus help the trees return to health? Should we get a soil test to determine what may have killed the trees with the fungi? It will be tough, but keeping the deer off our property also help?
A soil test will not help.
Dead branches should always be removed from otherwise healthy trees, but if you have a dying tree, then removing dead branches will not make any difference.
You may want to have a certified arborist come look at the situation. We recommend using arborists that are certified by the International Society of Arboriculture (ISA). They generally work for tree service companies. Usually, the companies do not charge for their arborists to come appraise the situation (just for work don), but ask beforehand.
To find a certified arborist, follow the prompts at www.treesaregood.org