Lily Leaf Beetle

Encyclopedia Article

A bright red lily leaf beetle on the tip of a lily leaf. Photo by Richard A. Casagrande, University of Rhode Island, Bugwood.org.
A bright red lily leaf beetle on the tip of a lily leaf. Photo by Richard A. Casagrande, University of Rhode Island, Bugwood.org.

Description of lily leaf beetle 

The adult insects have a distinctively bright red body with a black head, and about ¼-inch-long. They have no spots, stripes or other markings. The larvae are greenish to orange in color, up to 3/8-inch-long and slug-like in appearance and are active from May to June.

Lily Leaf Beetle on a plant. Photo by Kenneth R. Law, USDA APHIS PPQ, Bugwood.org
Lily Leaf Beetle on a plant. Photo by Kenneth R. Law, USDA APHIS PPQ, Bugwood.org.

Damage caused by beetle

The lily leaf beetle, a native of Europe and Asia, first appeared in the U.S. in 1992, and most common in the Northeast. It was recently confirmed to be present in Minnesota, and the Iowa State Plant and Insect Diagnostic Clinic has confirmed a likely presence in Iowa through photos.

The lily leaf beetles are present in the garden from May until September and feed on true lilies (Lilium spp.) and fritillaries (Fritillaria spp.). Adults chew holes in the leaves, feed on the stem, flower buds and flowers. The defoliation caused by the lily leaf beetle can severely damage plants. 

They will also feed on lilies of the valley and Solomon’s seal but less often; however, daylilies (Hemerocallis spp.), canna lilies (Canna spp.) and calla lilies (Calla palustris) are not consumed by the invasive insect.

If you spot a possible lily leaf beetle please report sightings here: 
Report lily leaf beetle sightings

 

Lily leaf beetles are mostly red. Photo by Leslie J. Mehrhoff, University of Connecticut, Bugwood.org
Lily leaf beetles are mostly red. Photo by Leslie J. Mehrhoff, University of Connecticut, Bugwood.org.

Multiple lily leaf beetles eating lily leaves. Photo by Leslie J. Mehrhoff, University of Connecticut, Bugwood.org.
Multiple lily leaf beetles eating lily leaves. Photo by Leslie J. Mehrhoff, University of Connecticut, Bugwood.org.

Last Reviewed: 
July, 2020
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