Bristly Roseslug

Shrub roses (Rosa spp.) in southwest Ohio are struggling with several issues. One of the most obvious problems is Rose Rust which is also unusual. Historically, rose rust has been rare in Ohio and more common in the coastal regions of the U.S.

When I started working for Extension back when growing roses meant hybrid teas, the dominant roseslug sawfly (order Hymenoptera, family Tenthredinidae) was Endelomyia aethiops. It was so common, the common name approved by the Entomological Society of America (ESA) for this species was simply Roseslug.

Heavy leaf damage from the non-native bristly roseslug sawfly (Cladius difformis) is becoming very apparent on its namesake host in southwest Ohio.  Roses in Ohio may be infested by this sawfly as well as two other non-native species:  the European roseslug sawfly (Endelomyia aethiops); and the curled roseslug sawfly (Allantus cinctus).  Despite their common names, the larvae of these sawflies resemble tiny caterpillars and look nothing like the glistening, elongated pear-shaped "slug sawflies" which do resemble tiny slugs.

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