My oak tree has very small branches covered with foliage down the length of the trunk. I find this unsightly, but don't want to damage the tree. Is it OK to cut them off?
Those suckers are called epicormic growth and it is a sign of stress.
Frequent watering is usually a death sentence for native oaks although some trees seem to maintain their health in spite of lawn water close by.
However, you cannot just cut off the water if the tree is used to it. Water it monthly in the summer for several hours.
Preservation is cheaper than removal and since your tree is in trouble, here are some things to consider.
1) Has the water been changed? Have drainage patterns changed in the area or is the irrigation greater or less than before?
2) Has there been root damage in the past from grade changes or trenching?
3) What species of oak? Blues grow slow and live long; Black and Valley grow faster and live a long time; interior live oaks grow fast and die young.
Could your oak just be really old?
4) Have you done what you can for the tree? Woody mulch, possibly summer water (many arborists now believe this is a good idea) and slow release fertilizer (half dose) in the early fall.
5) What are the symptoms? Really inspect the tree looking for leaf problems, oozing on branches or trunk, growths like conchs or mushrooms, trunk wounds and condition of the bark near the roots.
For more information visit Web site at ceplacernevada.ucdavis.edu