What Is That Sticky Substance on Apricot Trees?

Pest Identification

• Apricots are prone to infestation from aphids, the most common pest of plants, including shrubs, trees and ornamentals, according to the Colorado State University Extension. Many aphids are host specific, meaning they infest only certain types of plants. The green peach aphid is most likely to infest apricot trees. This species also effects other fruit trees in the Prunus family, including peach.

Description

• Aphids are very small, oval-shaped, soft bodied pests that measure less than 1/8 inch in length. The pests come in a variety of colors, often coordinating with the infested plants. They may be winged or wingless, depending on species. Aphids have long legs, antennae and a pair of tubes growing backward from the rear of the body. These tubes, called cornicles, are the distinguishing feature of aphids. Adults produce as many as 80 nymphs during a single week in warm weather. The offspring reach adulthood in about a week.

Damage

• Aphids are primarily sap feeders and suck juices from tender plant areas with their specialized, long mouth parts. The loss of heavy amount of sap effects plant health. As they feed, the pests produce excessive quantities of a sweet, sticky substance. This excess fluid waste is called honeydew. It is this sticky material that is seen on apricot trees. Honeydew invites secondary pests like ants, flies, bees and wasps into tree. It also promotes the growth of sooty, black mold. Severe damage to foliage leads to curling, wilting and discolored leaves. As a result, new shoot growth is stunted and there is dieback of buds.

Management

• To control aphids, you can Introduce natural predators into infested trees. These include certain species of parasitic wasps, lacewings, syrphid flies and lady beetles. Control ants in trees as they protect aphids from predators, the University of California recommends. Avoid excessive use of nitrogen fertilizer on trees. Use urea-based, slow-release fertilizers. Chemical control options include the use of neem oil, insecticidal soap, permethrin, acephate or malathion.