Roseslugs are the immature stages of primitive wasps called sawflies. Roseslugs look more like caterpillars than slugs. They are not slimy and do not have rasping mouthparts like true slugs. Roseslugs differ from caterpillars in that their abdominal legs do not have hooklike crochets to cling on to foliage or twigs. There are several species of sawflies that have been reared from roses in North America. Of these three species appear to cause the most damage: 1) The bristly roseslug, Cladius difformis (Panzer), 2) The roseslug, Endelomyia aethiops Fabricius, and 3) The curled roseslug, Allantus cinctus Linnaeus.

The bristly roseslug is found in Europe, Siberia, and in North America in Nova Scotia, Quebec, Atlantic Coast to British Columbia and down into southern California, It does not appear to occur in warm climates. This roseslug is pale green in color and is covered with many hairlike bristles all over the body. A full grown larva measures up to 16 mm (5/8 inch). The females are about 5/8 inch long and are shiny black with yellowish-orange markings on the body. The males are much smaller, about 3/8 inch long. The young larva begins feeding as a skeletonizer on the underside of the leaves and as it matures it chews large holes on the leaves. There are as many as six generations each year.

The European roseslug is found from California north to British Columbia and east to Quebec and the Atlantic Coast. It is also found in Europe. The adult sawflies are shiny back with a few yellow makings on the body. They measure about 3/8 inch in length. Females deposit their eggs singly in pockets along the margins of the leaves with their sawlike ovipositor. The larvae skeletonize the upper surface of the leaves. A full grown larva measures up to 13 mm (=1/2 inch). This species appears to have only one generation per year
I think Bt would get rid of them or some Sevin the first is organic

Thank you so much! I will try it tonight.