Tree health - Ask Extension
I have a very old black locust that lost a limb this past July in a wind storm. I'm trying to weigh my options as to what to do. I hate to take it d...
Knowledgebase
Tree health #922872
Asked December 15, 2025, 11:55 AM EST
I have a very old black locust that lost a limb this past July in a wind storm. I'm trying to weigh my options as to what to do. I hate to take it down as it is only one of three trees on the block. Short of a $2000 dollar assessment by Davey Tree I'm wondering if there is anything else I can do to assess the overall health of the tree. I was hoping to do some type of drilling to see if I could tell if the trunk is fairly solid or if it is rotted.
Can you offer any advice?
Ramsey County Minnesota
Expert Response
Given the age of the tree and your concerns, it is best to consult a professional arborist for an assessment. Call several and ask about fees; you may find one who has reasonable costs. Be aware, however, that black locust trees are considered invasive in Minnesota.
Drilling into the tree can lead to decay. Try these other tests instead to help check for decay that's already present. Look for fungal growth at the base of the tree; these are indicators for decay. Extensive cracks or peeling park are also indicators. A thinning leaf canopy can be the result of the tree's difficulty in transporting water to its branches. Tap the tree's trunk; if it sounds hollow it indicates decay. If you can rock the tree a bit in any direction, this would also indicate root decay.
Here is information on finding an arborist and general information on black walnut trees in Minnesota: https://trees.umn.edu/black-locust-robinia-pseudoacacia
https://extension.umn.edu/planting-and-growing-guides/how-hire-tree-care-professional
Good luck in determining your tree's health.
Drilling into the tree can lead to decay. Try these other tests instead to help check for decay that's already present. Look for fungal growth at the base of the tree; these are indicators for decay. Extensive cracks or peeling park are also indicators. A thinning leaf canopy can be the result of the tree's difficulty in transporting water to its branches. Tap the tree's trunk; if it sounds hollow it indicates decay. If you can rock the tree a bit in any direction, this would also indicate root decay.
Here is information on finding an arborist and general information on black walnut trees in Minnesota: https://trees.umn.edu/black-locust-robinia-pseudoacacia
https://extension.umn.edu/planting-and-growing-guides/how-hire-tree-care-professional
Good luck in determining your tree's health.
