SAMPLING WESTERN HEMLOCK LOOPER PUPAE (LEPIDOPTERA: GEOMETRIDAE) USING BURLAP TRAPS

Burlap wrapped around western hemlock, Tsuga heterophylla (Raf.) Sarg., trees at breast height was used to trap pupae of the western hemlock looper, Lambdina fiscellaria lugubrosa (Hulst). The number of pupae in the traps was highly variable and was not related to tree diameter or the surface area of the trap. There was a significant relationship between the number of viable pupae per trap and the number of healthy western hemlock looper eggs subsequently laid on lichen in the trees. Sample size requirements are presented.