Lily Leaf Beetle
Thursday, 28 May 2009 00:00
Lily leaf beetle adults are active, feeding on foliage of Asiatic lilies and mating. Eggs have been laid and are hatching. Monitor for the bright red beetles and also for the eggs on the undersides of the foliage. Inspect the leaves for fine tan-colored, irregular-shaped lines about one inch long. On closer examination, these tan lines will be a row of eggs. Just before hatching, these eggs turn a bright red color. When eggs are found, they can be removed and destroyed. Lily leaf beetle has now been reported in Berkshire County (MA) for the first time.
If your customers only have a few plants in their garden, hand-picking adults and eggs can be effective. Products containing neem (Bon-Neem, Azatin), a botanical insecticide, have been shown to kill very young larvae but must be applied every five to seven days after egg hatch. Products containing the systemic imidacloprid are providing effective control applied either as a foliage spray or soil drench depending on label instructions. Imidacloprid is the active ingredient in Marathon and Merit and one of the active ingredients in Bayer Advanced Rose and Flower Insect Killer for home gardeners. Products containing spinosad a microbial insecticide, are effective on larvae. Spinosad is sold as Conserve and Entrust for commercial growers and Monterey Garden Insect Spray, BULL’S-EYETM and others for home gardeners.
Lily Leaf Beetle Biological Control Survey 2009
If you grow or sell lilies in RI and Eastern Massachusetts (especially within a 10 mile radius of Wellesley), and have lily leaf beetles feeding on them, the University of Rhode Island would like your help. The University of Rhode Island (URI) Biological Control Lab is researching natural enemies of the lily leaf beetle. Small parasitic insects were established in lily plots in Cumberland, RI, and Wellesley, MA. URI researchers hope that the insects will disperse naturally from these release sites, eventually reducing problems with the lily leaf beetle throughout New England.
URI would like to track these parasitic insects by collecting the large larvae covered with excrement (brown blobs) that you find on your lilies. They will dissect the larvae to look for the parasitic insects. If you or customers you know have larvae, and wouldn’t mind sending them to URI please use the following instructions to send them to Lisa Tewksbury at the URI Department of Plant Sciences or contact her for more information. Instructions and more information
More information on LLB
Photos: Larvae Eggs Adullt Beetle
Lily Leaf Beetle Fact Sheet, UMass
University of Rhode Island Bio Control Lab (includes photos of parasitic wasp)
Evaluation of resistance to Lily Leaf Beetle in Lilium spp. Cultivars
Tina Smith, University of Massachusetts
