Unhealthy trees - Ask Extension
I live on a wooded lot in Calvert County. There are many massive trees on the property, some within close proximity of the house. Recently several v...
Knowledgebase
Unhealthy trees #924829
Asked February 20, 2026, 9:31 AM EST
I live on a wooded lot in Calvert County. There are many massive trees on the property, some within close proximity of the house. Recently several very large trees have fallen. Now a huge limb has fallen and it is hollow inside. I need a reputable specialist to access the trees to determine which trees are unsafe. I am at a loss as to how to best go about this. I would appreciate any advice that you can provide.
Calvert County Maryland
Expert Response
You can search for a certified arborist on the linked page, which has a database maintained by the ISA (international society of arboriculture, the organization that certifies arborists). You can also check the database of the American Society of Consulting Arborists, who also should be ISA-certified. Maryland licensed tree experts may or may not have ISA certification in particular, but to have that credential, they too pass an exam that is similar to the ISA exam.
Diagnosing dead or dying trees can be challenging, since often symptoms arise only well after decline has begun, often preceded by injury or stress (flooded roots, drought, etc.). Arborists can't treat or cure every condition, and it's common for overlapping issues (drought stress that attracted wood boring insects, or old storm damage that was infected by wood decay fungi) to have contributed to dieback and breakage as the wood dries out and becomes more brittle. As a generalization, the recurring droughts on the past few years, and the excessively wet seasons in 2018 and 2019 have caused lots of stress for trees, which can predispose them to other issues like borers and fungal attack. At the very least, though, a certified arborist or tree expert should be able to evaluate the safety of concerning trees to determine how at-risk of falling they may be. Some arborists have an additional certification, TRAQ (tree risk assessment qualification), where they have greater expertise or training in determining the safety or hazard of a compromised tree.
Miri
Diagnosing dead or dying trees can be challenging, since often symptoms arise only well after decline has begun, often preceded by injury or stress (flooded roots, drought, etc.). Arborists can't treat or cure every condition, and it's common for overlapping issues (drought stress that attracted wood boring insects, or old storm damage that was infected by wood decay fungi) to have contributed to dieback and breakage as the wood dries out and becomes more brittle. As a generalization, the recurring droughts on the past few years, and the excessively wet seasons in 2018 and 2019 have caused lots of stress for trees, which can predispose them to other issues like borers and fungal attack. At the very least, though, a certified arborist or tree expert should be able to evaluate the safety of concerning trees to determine how at-risk of falling they may be. Some arborists have an additional certification, TRAQ (tree risk assessment qualification), where they have greater expertise or training in determining the safety or hazard of a compromised tree.
Miri
