Forsythia (Forsythia)-Root weevil

Lilac root weevil (Otiorhynchus meridionalis) and numerous other species

Pest description and damage Identification is important as root weevil species differ in susceptibility to pesticides and may have different life cycles. Adult weevils are dark colored and nocturnal, from 0.2 to 0.25 inch in length. East of the Cascades, the lilac weevil is especially common. Look for regular U-shaped notches along the leaf edges. This is species is unusual because males are common and adults are often found in tandem. These nocturnal adults are nearly black and shiny with a snout (rostrum) and elbowed antennae. Larval feeding on roots is rarely a problem in established landscapes.

For biology, life history, monitoring and management

See "Root weevil" in:

Management-chemical control

See Table 2 in: