Adelges abietis (Adelgidae)

the eastern spruce gall adelgid


Adults:

Similar to A. cooleyi.

Nymphs:

Also similar to A. cooleyi above.

Damage:

Characteristic pineapple-shaped galls caused by Adelges abietis on spruce. Nymphs overwinter under wax threads at the base of buds. Expanding buds are attacked in the spring causing the formation of pineapple-shaped galls. Galls open in the fall and winged adults emerge to lay eggs on the bark. Migration to new hosts occurs. There is one generation per year. Compare gall shape and location on the tree with those of A. cooleyi.



Principal Hosts:

Attacks native and ornamental spruces in B.C., Alberta, and Saskatchewan. Also a serious pest in nurseries and Christmas tree plantations in eastern Canada. No secondary host is known.

Economic Importance:

Galls disfigure ornamental and Christmas trees lowering monetary and aesthetic values.

References and Links:

FC: 103.

Additional Images:
Pineapple galls of A. abietis on spruce.

Photo from:E. Bradford WalkerVermont Department of Forests, Parks and Recreation, USA, Bugworld.org