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.
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