Question
There has been a drought this year, but last year I did not spray for those terrible green worms that come on the live oaks every couple of years. This should help you figure out the problems.  I also have sprinklers up on a tree well around the tree with 360 heads of them so that I could also water the Live Oak inside.  But - the tree looks like it has dead and dying parts on the outskirts of the limbs and in particular up at the very top part of the tree, what could be the cause? In the specifications for this type of tree it states that they like moisture, so
could I still not be watering enough? Is that possible?  We just built the home we are in, and they just placed the tree well around the tree which is quite large cause the tree is monstrous, I am guessing that it goes up as high in places as 50 feet.  I did have a lot of pruning done when I first moved in also, but can't figure out why not more than 25 to 30 feet are three more live Oaks doing well that is not on my property. They are doing nothing to theirs that I am not.  Maybe you can help is it not enough water, in drought years do I need to put a hose in there and water by drip for several days or what? Afraid to do anything cause I am afraid I may exacerbate the situation without knowing what is wrong. Thanks so much for your help which is greatly appreciated.  Rosemary in Georgetown

Answer
If I get this right the well around the tree was recently put in and fill dirt was added around the tree? If so that sounds like the problem.  Even a few inches of fill or soil removal can cause extensive root damage. If possible, never remove soil from or add large amounts of soil within the drip line. When soil air is decreased by filling, certain gases and chemicals increase and become toxic to roots. Symptoms may appear within months or years after filling has occurred. The extent of injury from filling varies with the species, age, and condition of the tree; the depth and type of fill; and drainage. Beech, dogwood, most oaks, pine, sugar maple, spruce, tulip popular, and walnut are the most easily injured. Elm, locust, pin oak, sycamore, and willow are the least effected. Clay soils cause the most damage because the fineness of the soil shuts out air and water more than a gravelly or coarse soil. Three to four inches of soil can be added to small areas under the tree provided the soil texture is coarser than the native soil. Finer textured soils should not be used for filling.

If a tree well is to be constructed, built a wall no closer than the dripline and grade the soil outside of the tree well so it drains away from the tree. Success has been reported in some cases where gravel was spread over the existing grade and vertical pipes were installed every 10 feet before the area was covered with a coarse-textured fill soil. Building a tree well several feet from the trunk of a tree before adding several feet of soil will do little to prevent root death.

The drought added to this. Most tree roots are located within the top 3' of soil. However, because the majority of the fine roots are concentrated in the top several inches of soil, minor soil disturbances can injure or remove a large portion of the absorbing roots on a tree. The majority of the roots system is about 1 1/2 times the foliage spread. Any watering should be done that covers this are. I think the tree is not getting enough water down to the roots that are left. Sounds like you are watering the well area. A tree needs about 1 inch of water per week across the area under the tree. Place a pan under the tree under about half way out from the trunk to the outer branch ends. Turn the sprinkler on and when the pan gas 1 inch of water in it stop. In this situation with the drought I would try this every third day until it rains.

IF you are in the US I would call the local office of the State Forestry agency or the Agricultural Extension Service and ask on of their Foresters to come take a look and advise you. This is free service and they can see things that I can not vision by a written description. Their number should be in your local phone book.