Today started off well as I found my first hairstreak larva of the year on the 4th tree I checked! The caterpillar was resting on the lichen-covered bark beneath the burlap on a white oak and does not seem to be prepupal. It is a small lime-green lycaenid covered in relatively long pale setae with a darkened anterior patch and posterior strip on the dorsum. The dorsum and sides are ornamented with pale streaks. I believe this is a middle instar Banded Hairstreak (Satyrium calanus). Compare here to photos of late instars taken by Sam Jaffe: http://www.pbase.com/spjaffe/image/112981413. I found this hairstreak larva in the same white-oak-rich area between the gravel parking lot and road to the observatory where I found a White-M larva in last year. Perhaps this is a particularly productive and favored area for oak-feeding hairstreaks? I will be sure to check carefully.
Banded Hairstreak (Satyrium calanus)
Burlap banding has proven to me to be a fruitful sampling method for many caterpillar species as well as a slew of other invertebrates (beetles, ants, spiders, centipedes, etc.). The attractive hiding places also occasionally host adult moths like the beautiful Green-dusted Zale (Zale aeruginosa) I found this morning. Dragonflies, like this Swamp Darner (Epiaeschna heros) I saw last June, will sometimes rest on the burlap skirt to bask in the sun or devour a freshly caught prey item.
Green-dusted Zale (Zale aeruginosa) found under burlap
Swamp Darner (Epiaeschna heros) resting on burlap
Oak Hairstreak Study 