Landscape - Cool Weather Favors Aphids; Look for Aphid Predators

Aphids are very common in spring on a large variety of plants because the weather favors them over their enemies like lady bug beetles, lacewings, and hover flies (Syrphid flies). This is more prenounced in a cool spring like we have been having. The following are images and information on the natural controls of aphids.

Aphids are found predominately on the undersides of leaves. Aphid feeding often causes leaves to curl under making it difficult for predators to reach them. Aphid populations explode quickly because they are all females giving live birth to females, which will soon be giving live birth to females. Insecticides may not be necessary if there are enough predators present. Look for the adult lady bug beetles and their larvae (they look like alligators), lacewing larvae (with long scissorlike mouthparts extending out of their heads) and hover flies (tiny sluglike larvae).

Green lacewing larve feeding on aphid. Photo by Whitney Cranshaw, Colorado State University, Bugwood.org

Syrphid (Hover) fly larvae, a predator of aphids. Photo by Whitney Cranshaw, Colorado State University, Bugwood.org

Lady beetle larvae, a predator of aphids. Photo by Frank Peairs, Colorado State University, Bugwood.org