Problem Identifier Unit Screen//v.w/ RR Template

Problem Identifier Unit Screen//v.w/ RR Template Aphids

Problem
Needles are discolored and may be deformed; many may drop from the tree. New growth is often slowed, and twigs may die. A shiny, sticky substance often coats the needles and branches. A black sooty mold may grow on the sticky substance. Small (up to 1/6 inch), green, brown, or black soft-bodied insects cluster on the needles, twigs, or main stems of small trees. An uncontrolled infestation may kill young trees.

Analysis
(Cinara species and Eulachnus species)

Several different types of aphid infest the needles or bark of pines. Aphids do little damage in small numbers. However, they are extremely prolific and populations can rapidly build up to damaging numbers during the growing season. Damage occurs when the aphid sucks the juices from the pine needles, growing tips, or bark. The aphid is unable to digest fully all the sugar in the sap and excretes the excess in a fluid called honeydew, which often drops onto the needles and bark below. A sooty mold fungus may develop on the honeydew, causing the pine needles, bark, or other coated plants to appear black and dirty. Ants feed on this sticky substance, and are often present where there is an aphid infestation. For more information about aphids, see Aphids.

Solution
Control with an insecticide containing acephate or malathion, or an insecticidal soap when aphids first appear. Repeat the spray if the tree becomes reinfested in mid- or late summer. Be sure to check the tree in the fall as well.

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