Both males and females have fully formed wings and look similar. Wings variable in coloration: light or dark gray, or brownish. Median area not lighter than the rest of the wing.
This is one of the largest geometrids in North America, and has a very solid, hairy body.
In fact, this moth is so thickly built that some people might mistake it for a noctuid on first glance...see Panthea pallescens, for example.
L. ursaria can have some brown on the wings, or reddish brown on the abdomen, but the overall color is always gray. L. ypsilon is generally much more colorful (yellow, brown, etc) and contrasty, with a light median area.
Distribution pattern: Northern.
Reilly pers obs
These moths emerge in early spring.
Generalist. Feeds on deciduous trees and shrubs including: Acer, Alnus, Malus, Populus, Prunus, Salix, Ulmus, Vaccinium (Tietz 1972).
Rindge FH. 1975. A revision of the new world Bistonini (Lepidoptera Geometridae). Bulletin of the American Museum of Natural History 156(2): 71-155.
McGuffin WC. 1977. Guide to the Geometridae of Canada (Lepidoptera) II. Subfamily Ennominae. 2. Memoirs of the Entomological Society of Canada 101: 1-125.
Covell CV. 1984. A field guide to the moths of Eastern North America. Houghton Mifflin Company: Boston. 496 pp.
Tietz HM. 1972. An index to the described life histories, early stages and hosts of the macrolepidoptera of the continental United States and Canada. A.C. Allyn: Sarasota, FL. 1041 pp.