Western false hemlock looper, Nepytia freemani
 

Fig. 31   Late instar larva of western false hemlock looper. Note square head and alternating dark and light stripes.	Fig. 32  Feeding by western false hemlock looper begins in new foliage of tree tops	Fig. 33  Western false hemlock looper larvae gradually consume older foliage further down the crown.

Distribution:  Primarily occurs in the IDF biogeoclimatic zone, most often occurring in Douglas-fir stands growing on dry, rocky sites.

Tree Species Attacked: Primarily immature Douglas-fir trees are attacked, and occasionally hemlock, Engelmann spruce, sub-alpine fir, ponderosa pine, and larch.

Insect Description & Damage Symptoms: The "inch worm" larvae start feeding with the flush of new growth in the spring. Mature larvae have a broad, reddish-brown dorsal stripe bordered by narrow yellow stripes. Each side is marked with a wide yellow stripe. The larvae are approximately 3 cm long. The head appears almost square from above and has black dots. The pupae are light amber, becoming dark red-brown, 1.2 to 2 cm long, and are loosely contained in a cocoon of woven hairs. Feeding begins in May in the upper crown on the underside of newly flushed foliage. In late June through August, the larvae move down the crown and consume older foliage. Most needles are only partially eaten. Larvae are solitary feeders but may gather in webbed enclosures to pupate. Defoliation becomes noticeable in June. Abundant webbing is evident in heavily infested stands.

Damage: During serious outbreaks, trees may be completely defoliated in one season. Douglas-fir usually recovers from a single defoliation. Repeated attacks, however, can result in top-kill or mortality.

Similar Damage: Damage is similar to other defoliators, such as the western spruce budworm, but the larvae are very distinctive.

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BC Ministry of Forests
Forest Practices Branch
P.O. Box 9513 Stn. Prov. Gov.
Victoria, BC
V8W 9C2

Section phone: (250) 387-8739
Section fax: (250) 387-2136

Last updated March 04, 2002