QuestionI live in Houston on a golf course. about 5 yrs ago, the GC sprayed herbicide to kill St. Augustine growing onto the course and it drifted onto my Shumard red oak. The tree is now about 11 years old and has suffered every year since with leaves browning and curling and dying. This year it has looked better than other years, but there are large (8"x5")oval deformities in the bark on the trunk starting at 6' and going upwards. Inside the oval deformity, there is no bark. Do you think this tree is slowly dying and should it be cut down? It still shows stress every year.
AnswerAs long as the foliage is green and looks healthier than the last year I would not cut it down. The "deformities" sounds like a canker disease. Canker disease generally do not kill the tree but may be brought on from the stress of the spraying. I would fertilize it with 10-10-10 fertilizer at about 1 lb of fertilizer per inch of trunk diameter spread evenly around the tree under the foliage dripline. and watered in good. I would fertilize now and again in the spring. make sure you do not use a weed and feed fertilizer that is used on lawns this will damage the trees roots.
