Apple pith moth

Insect

Apple pith moth

Blastodacna atra (Haworth)

Lepidoptera: Agonoxenidae

Distribution: ME, NH, MA, CT, RI.

Photos

Larval feeding causes leaf wilt and die-back of blossoms and terminal shoots.

Larval feeding causes leaf wilt and die-back of blossoms and terminal shoots. Alan Eaton, Univ. of NH
C

Head of adult is covered with white scales; forewings are narrow, mostly black or dark brown with white marks and usually with an irregular faint, rusty yellow line in the middle, and with two prominent black scale tufts. When the wings are folded they appear to have three pairs of white spots (A). Young larva is yellowish with a dark brown head, but turns more reddish in color in the final instar (B).

  • Crops Affected: apples

    Damage

    Attacks apple. Damage is most noticeable in the spring, either just before or after bloom, when the larvae are actively feeding in the woody tissues at the bases of new shoots of apple trees, causing leaf wilt and die-back of blossoms and terminal shoots (C). The larvae usually attack spurs and the stems of apical shoots, which stimulates the growth of laterals.

    Management

    Effective control can be obtained by the application of an insecticide in late summer (about 2 months after petal fall), when adults are active, as well as early spring, when overwintering caterpillars emerge from their shelters.

About

Resources

Events

Michigan State University
  • Spartans Will.
  • © Michigan State University

MSU is an affirmative-action, equal-opportunity employer, committed to achieving excellence through a diverse workforce and inclusive culture that encourages all people to reach their full potential.

Michigan State University Extension programs and materials are open to all without regard to race, color, national origin, gender, gender identity, religion, age, height, weight, disability, political beliefs, sexual orientation, marital status, family status or veteran status. Issued in furtherance of MSU Extension work, acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture. Quentin Tyler, Director, MSU Extension, East Lansing, MI 48824. This information is for educational purposes only. Reference to commercial products or trade names does not imply endorsement by MSU Extension or bias against those not mentioned.

The 4-H Name and Emblem have special protections from Congress, protected by code 18 USC 707.

We comply with the Federal Trade Commission 1998 Children’s Online Privacy Protection Act (COPPA).