Caterpillars in Your Yard and Garden - Page 28
Loopers and cankerworms
Linden looper caterpillars (Erannis tiliaria) are present from late spring to summer. They produce one generation per year.
Full-grown larvae are nearly 1.5 inches long and have rusty-brown heads. The body is yellow, and on the dorsal side there are several (up to 10) thin, wavy black lines running longitudinally. The sides of the body surrounding the spiracles are bright yellow and the ventral side is pale. Preferred host plants include maple, oak, hickory, elm, birch and apple.
About the family
Loopers and cankerworms in the Geometridae family characteristically have only two pairs of prolegs (one mid-abdominal pair and one anal pair). They travel by means of a looping movement rather than a crawling action. The color patterns of many species mimic the foliage, stems or twigs of their preferred host plant.