Page 623 - The Book of Caterpillars: A Life-Size Guide to Six Hundred Species From Around the World

MOTH CATERPILLARS

FAMILY Noctuidae
DISTRIBUTION Southern Canada and United States, except southern and
central areas

HABITAT Wet meadows, woodlands, riparian areas, and hop elds
HOST PLANTS Hops (Humulus spp.), nettles (Urtica spp.), and woodnettle
(Laportea spp.)
NOTE Looper caterpillar that can be a serious pest of hops
CONSERVATION STATUS Not evaluated, but usually common

ADULT WINGSPAN
1–1¼ in (25–32 mm)
CATERPILLAR LENGTH
1–1 ⁄ in (25–30 mm)
HYPENA HUMULI
HOP LOOPER 621

HARRIS, 1841

Hop Looper caterpillars hatch from eggs laid singly in spring
on host plants, such as hops, some three days earlier. Prior
to ovipositing, the adult females overwinter in caves or old
buildings. After hatching, the caterpillars develop rapidly, taking
just 14 days at 78.8°F (26°C) to reach maturity. The larvae move
with a characteristic looping motion and feed mostly by night.
Pupation occurs in a slight, silken nest between leaves or on the
soil surface, and the adult moths emerge after nine to ten days.
There are two to three generations annually.

Hop Loopers sometimes occur in large numbers in hopyards
in the northwestern United States and can defoliate hop vines.
However, up to 70 percent of Hop Looper caterpillar populations
may be parasitized by the many species of parasitic wasps and
ies that attack them. Adult moths can sometimes disappear
from an area, and it is suspected that they migrate. As adults are
attracted to a combination of acetic acid and 3-methyl-l-butanol,

traps containing this mixture are proving an e ective monitoring
tool for this species.

The Hop Looper caterpillar is pale green with
thin, white, subdorsal and spiracular stripes.
The setae are ne and pale golden orange to
brown, and the spiracles are small. The head
is shiny green, usually with scattered minute
black spots, which also occur on the body. Actual size