This column is a new addition to the Cochise County Master Gardener Newsletter. As a County Agent for Horticulture, I receive many questions about various and sundry matters. My intent is to answer some of the questions I receive to assist you in gaining more knowledge.

QUESTION: What are these larvae and small bugs on my elm tree?

ANSWER: This insect is the elm leaf beetle, Pyrrhalta luteola and is found throughout North America wherever elm trees are grown, mainly in urban areas. The beetle overwinters in seclusion, often in buildings and under plant debris. In the spring they emerge, lay eggs, and feed on new leaves. Eggs hatch in about a week as dull yellow larvae with two dark stripes which skeletonize leaves. The adult beetle is 6 mm long and vary in color from yellow when young to olive green when mature, with black stripes down the margins of each wing cover. Tree leaves can be severely damaged thus weakening the tree and allowing other infections or diseases to attack.

Control: Natural enemies include birds and predaceous and parasitic insects and disease. The chalcid wasp kills pupae. Chemical control is accomplished by spraying or using systemic soil drench when eggs are hatching, normally in late April or May. If a good job is done early usually nothing is needed for subsequent generations during the year. (Source: Insect Pests of Farm, Garden, and Orchard. R. H. Davidson and W. F. Lyon. 7th Ed., P. 369.)

QUESTION: My apricot and poplar tree leaves are torn and ragged looking with occasional holes. Also, the fruit has sunken spots and the flesh under the spots is turning brown. There are no signs of insects. What is happening?

ANSWER: This spring we have had an abnormal rainfall. Also, there have been several hailstorms. The hail has torn your leaves and bruised the topside of your fruit.

Control: If a hailstorm is predicted throw a blanket or piece of plastic over your trees and plants to cushion them from the hails' impact. The plant will usually grow out of hail damage, however severe damage can cause young, tender plants to die.