Elm leaf beetles can be serious pests of elm throughout Colorado. The insects feed on elm leaves and cause them to dry up and die. Heavily infested leaves die and give trees an unsightly, general brown color. Repeated injuries also weaken trees and make them prone to branch dieback and wind injury. Elm leaf beetles favor Siberian elms, but all elm species may be damaged during beetle outbreaks.
Elm leaf beetles also are common nuisance pests in houses. Large numbers of beetles may seek overwintering shelter in and around homes. Masses of beetles become active in late winter and spring and can be found crawling on windows and furnishings. Although elm leaf beetles do not reproduce indoors, their presence often causes concern.
ArborScape's curative sprays, timed twice a year to correspond with the destructive larval stage of the beetle, controls their numbers and disrupts reproduction. The number of affected leaves and subsequent infestation of nearby buildings drops sharply when these sprays are implemented.