Question
We have three cypress trees that are on the property line in our back yard in Mississippi. The cypress tree knees have taken over our back yard and are not coming up in our above ground pool causing leakage. Is there anything we can do to get rid of the knees? Our neighbor does not want to cut the trees down so we feel like our hands are tied. Please help so that our children can continue to enjoy the swimming pool without all the cypress knees. Also, we do not mind if the tree dies.

Answer
Cut the knees off at the ground level and paint the cut stump with a herbicide called Roundup. Use a small paint brush and the Roundup straight from the container. Discard the brush after you have finished. The stump will transport the herbicide to the roots near the knee and stop the roots from sprouting new knees. Treat the stump as soon as you cut the knee for the best results.