Bud moths, Zeiraphera spp.  

Fig. 10   Bud moth larvae on larch needle clusters. Body colour varies.	Fig. 11, Bud moth feeding damage to larch needle cluster.	Fig. 12 , Bud moth attack on true fir showing resultant leader damage.	Fig. 13  Frass on bud indicates bud moth feeding. Note retention of bud cap

Distribution:  Throughout B.C. following the range of spruce and larch.

Tree Species Attacked: All ages of spruce and larch are attacked, and occasionally true firs. 

Insect Description & Damage Symptoms: Larvae are up to 1.4 cm long when fully grown. Larval body colour is variable and may be any of the following: pale green, dirty white, pale yellow, or yellowish-green to purplish-brown. Light brown spots may be present on the back or side of the larvae. The heads are broad and black when young, but eventually turn brown. Larvae drop to the ground by August and pupate in the litter layer. Bud moth larvae feed only on the current year's foliage. On spruce, the larvae attack recently flushed buds. Many larvae secure the bud cap to the bud with silk strands and feed on the new foliage under the shelter of the bud cap. This type of feeding is not conspicuous at first, but later in the season, most attacked buds will retain their caps while healthy buds will not. Larvae may create feeding shelters by chewing needles off at the base and attaching them to twigs. On larch, young larvae feed on developing needle clusters. Older larvae construct tube-like structures from needle clusters and webbed tunnels along the branch axis, or they may feed directly on needles.

Damage: Since bud moths feed on current growth only, damage is limited to growth reduction and distortion of crowns. In some cases, however, this damage is extensive, causing reduction in stand performance, especially in young plantations.

Similar Damage: Moderate larch sawfly damage is similar, but the larvae are easily distinguished from each other. Larch casebearer damage may appear similar from a distance, but closer inspection will show mined needles, as opposed to the chewed needles of the bud moths. At a distance, bud moth damage could be confused with white pine weevil damage.

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Contact Tim Ebata if you have comments on the presentation of this information.

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