Elm Leaf Beetle—Pyrrhalta (=Xanthogaleruca) luteola
The elm leaf beetle is an introduced pest from Europe which feeds only on elm. Although most elm species are subject to attack, the beetles usually prefer Siberian elm and hybrid elms. Elm leaf beetle feeding damage may result in partial or complete defoliation of the tree. Feeding damage by elm leaf beetles seldom kills an elm tree, however, severe feeding will weaken a tree, making it more susceptible to attack by other pests.
Adult beetles are about ¼ inch long, with yellowish legs and antennae. The body is yellowish to green with several black spots on the head and thorax and a black colored stripe on the outer margin of each wing cover.
Larvae are dirty-yellow to black, spiny and grow to ½ inch.
Adult beetles eat small round holes in the leaves, but the larvae completely skeletonize the leaves from the undersides. When damage is severe, the leaves dry, curl and fall prematurely.
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Identification and Control Information
- Elm Leaf Beetle—Maine Forest Service
- Entomological Notes: Elm Leaf Beetle (PDF)—Penn State College of Agricultural Sciences Cooperative Extension
- Landscape & Ornamentals: The Elm Leaf Beetle (PDF)—Purdue University Extension
More Information
- Maine Forest Service: Conditions Reports (updated regularly) including annual summary reports
[Photos, left to right: Clemson University - USDA Cooperative Extension Slide Series, Bugwood.org; Whitney Cranshaw, Colorado State University, Bugwood.org; James Solomon, USDA Forest Service, Bugwood.org]