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Trees/killing cypress tree knees


If roundup is used on the knees, how long would it take before it would kill the tree?

. If you want to get rid of the cypress trees then apply a herbicide called Roundup to the fresh cut knee and the roots will transport the herbicide to the tree and other roots and kill the tree. I would get an old paint brush and paint the stump with the Roundup straight from the container. Throw the brush away after you finish.  

The time will depend on the size of the tree. IF you want to speed this up cut a slit around the trunk of the tree cut into the wood and put the round up in the slit. This will be picked up by the tree and the death will be much faster. I would apply the roundup this spring as the new growth starts thie will be moved up into the tree faster in the early spring.  


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Jim Hyland


I am an expert in Forestry, Forest Entomology, Forest Pest Control, and Forest Health. Extensive knowledge in Identification of insects and diseases of trees. Expert on Bark beetles and other insects that attack forests. Also a Registrated Forester with extensive knowledge in the management and care of forests.


34 years as State Pest Management Chief in a Southern state. Extensive knowledge in Forestry.

BS with major in Forest Management and Entomology
Registered Forester
Certified Pesticide Appicator

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