Published by Utah State University Extension and Utah Plant Pest Diagnostic Laboratory
ENT-244-23
July 2023
Boxelder Leafroller Marion Murray, IPM Specialist and Ryan Davis, former USU Arthropod Diagnostician
Quick Facts • Boxelder leafroller is a caterpillar that feeds on leaves of boxelder, raspberry, birch, elderberry, white elm, and various shrubs. • It is a native species that usually occurs under low populations, but sometimes outbreaks can occur. • Adult boxelder leafrollers are buff-colored moths with wingspans of about 1 inch. Males are slightly smaller than females. • Mature larvae are almost 1 inch long, green, and very active when disturbed.
Fig. 1. Female (left) and male (right) boxelder leafroller moths.1
• Control is usually unnecessary, but if required, foliar sprays, including organic options, are available.
The boxelder leafroller, Archips negundana, is a pest of boxelder and other trees and shrubs in parts of the United States and Canada and is commonly found in Utah. Boxelder is the primary host, but damage can also occur on raspberry, birch, elderberry, white elm, and various shrubs. Adult females are buff-colored moths with a wing span of approximately 1 inch. The undersides of their abdomens are dark colored. Males are similar in appearance but are slightly smaller and light yellow on the underside of the abdomen. The larva is a greenish-yellow caterpillar that is 4/5 inch long when mature.
LIFE CYCLE Boxelder leafroller overwinters as eggs in cracks and crevices on its host. Eggs hatch soon after budbreak and the young larvae crawl to developing leaves and feed in small groups.
Boxelder Leafroller (Archips negundana)
Fig. 2. Boxelder leafroller larva.2 As larvae mature, they disperse and feed individually in leaves they have rolled with webbing. If a larva is disturbed, it will wiggle and quickly drop from the tree, suspended by a silken thread. Larvae typically complete development by mid-June and pupate (form cocoons) within the rolled leaves or in bark crevices. Pupation takes approximately 2 weeks. In northern Utah, moths may be present from late June through July. During this time, females mate and lay eggs in flattened masses of about 30 eggs, in branch forks and bark crevices. The egg masses are covered with scales from the female’s body and are difficult to detect. The eggs then hatch the following spring. There is one generation per year. Page 1