Cabbageworm: gregarious instars - Evergestis rimosalis
Wilmington, New Castle County, Delaware, USA
September 28, 2009
Size: ~1 inch and 1/4 inch
A BugGuide first for Delaware.
These caterpillars were usually gregarious in groups of 2 to 6. The age and larval instar didn't seem to matter.
Plant: Broccoli, Brassica oleracea var. Italica