Pest profile

Maple Shoot Borer

Proteoteras aesculana · Lepidoptera: Tortricidae[2]

Maple shoot borer larvae tunnel into young maple shoots, killing the tip and forcing a fork when the leader is hit.[1]

Maple shoot borer moth, a small mottled gray-brown moth with raised scale tufts, on a white surface
Maple shoot borer moth, a small mottled gray-brown moth with raised scale tufts, on a white surface. (c) David George, some rights reserved (CC BY) — via iNaturalist, CC BY 4.0

How to identify it

  • Each infested shoot has a small hole near a leaf stalk with a mass of sawdust-like frass mixed with silk.[1]
  • The adult is a very small light brown moth; the larva is a smooth cream-colored caterpillar with a black head.[1]

Where it lives

It occurs from Oregon and southern Alberta to the East Coast, and south through Kentucky and Tennessee to Mississippi.[1]

US map: public records from 35 states since 1990 (GBIF).

Biology and life cycle

Moths fly from mid-March to early May and likely lay eggs near opening buds; larvae bore into new shoots until late May or early June.[1]

Red and Freeman maples are the main hosts, and sugar maple is fairly common.[1]

Damage and signs

  • Shoots above the tunnel wilt and die, with flagging first showing in late April or May.[1]
  • In one UK study of newly planted red maples, up to 100 percent of trees were infested and 22 to 36 percent had a flagged leader.[1]

Health risk

It feeds on plants; UK Extension mentions no risk to people.[1]

Control

Traps and physical control

Through May, slicing open a flagged shoot reveals the tunneling larva, which confirms the cause.[1]

Biological control

Parasitoid wasps in the families Braconidae and Eulophidae attack it.[1]

Pesticides

In nurseries, one pyrethroid spray from just before bud break until shoots have two pairs of small leaves gave as much as 96 to 100 percent control.[1]

Common questions

Why did the top shoot of my young maple wilt in spring?
Maple shoot borer larvae tunneling in new shoots cause wilting and dieback from late April into May.[1]
Did my nursery tree come with the pest?
UK research found dormant liners aren't infested before shipping; eggs are laid shortly before bud break.[1]

Sources

  1. University of Kentucky Entomology (ENTFACT), “Maple Shoot Borer (ENTFACT-455).” entomology.mgcafe.uky.edu/ef455 (accessed 2026-10-06)
  2. iNaturalist, “Proteoteras aesculana taxon page (order and family).” www.inaturalist.org/taxa/228844 (accessed 2026-10-06)

Updated 2026-10-14. Built from sourced records. Spot an error? Tell us.