Question
2 years ago I purchased a Chinese elm.  It had grown and really was quite healthy until about 2 days ago.  I live in Tucson, AZ and it has been very hot, but nothing that this tree hasn't felt before.  In face, he did well.  3 days ago I began noticing that ALL the leaves on the tree began to curl up, turn light green and as of today, they are completely dry and dead.  The branches are bendy, but the entire tree looks like terrible.  Is the tree salvagable? What should I do?

Answer
Plant Guy:
These trees (Ulmus parvifolia) are very durable trees with a hardiness from zones 4 to 9. From your description, sounds as if things started to go south rather suddenly, which may indicate a potential trauma.  I would expect the source of the stress to be associated with an unfavorable root/soil environment rather than an infectious kind of disease. It is important to be sure that the tree gets adequate water to the roots during those hot/dry periods of summer.  These trees are quite forgiving--up to a point.  So check out the soil to be sure it is moist, not overly wet.  Also, look for any injury/damage to the bark on the main stem, especially on the trunk.  Things like lawnmowers and string trimmers are a death sentence to trees and shrubs. Since all of the leaves are curling, I would be suspicious of the root/soil issue.  However, do check the leaves for any signs of insect feeding just to be sure.  You might scratch a few smaller twigs with your fingernail and see if the tissue is green beneath.  This may indicate the health status of those smaller twigs and the likely-hood of releafing.

Steve