Overview

Elm Leaf Beetle is a serious defoliator of elm trees in Colorado. Both adults and larvae feed on leaves, with larvae being particularly destructive as they skeletonize foliage between the veins.

Signs of Infestation

  • Skeletonized leaves (only veins remaining)
  • Small holes in leaves from adult feeding
  • Yellow larvae on undersides of leaves
  • Premature leaf browning and drop
  • Reduced tree vigor

Treatment

Systemic treatments or foliar sprays applied at the right time can effectively control Elm Leaf Beetle populations. Multiple generations per year mean ongoing monitoring is important.