BRUCE SPANWORM

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Title: BRUCE SPANWORM
Description: LATIN NAME: Operophtera bruceata (Hulst) LIFE CYCLE: Overwinter as single eggs on twigs. Eggs begin to hatch at green tip and larvae present to petal-fall. Spend summer in soil as pre-pupae; pupate in late summer. Adults present October and November when eggs are laid. One generation per year. MONITORING: Examine host trees at tight cluster stage for larvae by visual examination or limb taps. Inspect fruit buds and leaves for signs of feeding damage. HOSTS: Fruit trees, willow, poplar, maple, alder. COMMENTS: Bruce spanworm larvae resemble green fruitworm larvae; however, spanwom larvae move by a characteristic looping movement and only have two pairs of prolegs (fleshy legs on abdomen) compared to five pairs for fruitworms. BODY LENGTH: Adult - 12.0 mm; Mature larva - 18.0 mm.