Skip to Left navigation Skip to Main content Skip to Footer

University of Minnesota Extension
www.extension.umn.edu
612-624-1222

Extension > Garden > Diagnose a problem > What's wrong with my plant? > Deciduous Trees > Birch > Parts of leaves missing

Print Icon Email Icon Share Icon

Birch > Leaves > Parts of leaves missing

1 of 6
  • Image: Whitemarked tussock moth 1
  • Image: Whitemarked tussock moth 2
  • Image: Whitemarked tussock moth 3

Whitemarked tussock moth
Orgyia leucostigma

  • Young larvae windowpane feed (i.e. feed on one layer of leaf tissue between veins) giving them a lacelike appearance
  • Older larvae consume entire leaves except the midrib and large veins; significant defoliation can occur
  • Caterpillars have a red-orange head with two sets of black tufts near the head; yellowish hairy body with distinct tufts of hair resembling a toothbrush on top of the body
  • Full grown larvae are 1 ¼ inches long
  • Two generations are present each year; the first from May to June and a second from August to September
2 of 6
  • Image: Forest tent caterpillar 1
  • Image: Forest tent caterpillar 2
  • Image: Forest tent caterpillar 3

Forest tent caterpillar
Malacosoma disstria

  • Larvae chew entire sections of leaves, sometimes leaving some major veins; defoliation can be severe when populations are high
  • Blue and black with characteristic footprint shaped white markings on top of body
  • Damage occurs May and June
  • More information on Forest tent caterpillar
3 of 6
  • Image: Fall webworm 1
  • Image: Fall webworm 2
  • Image: Fall webworm 3

Fall webworm
Hyphantria cunea

  • Chews entire sections of leaves, leaving major veins and can defoliate trees in high infestations
  • Produces silken webbing that covers the ends of branches; silken tent filled with frass and leaf segments
  • Yellowish or greenish with long, fine white hairs with two rows of black spots down its back; approx. 1 inch long when fully grown
  • Damage occurs from late July through September
4 of 6
  • Image: Yellownecked caterpillar 1
  • Image: Yellownecked caterpillar 2
  • Image: Yellownecked caterpillar 3

Yellownecked caterpillar
Datana minnistra

  • Young larvae feed in groups and skeletonize leaves by eating the leaf tissue and leaving the veins.
  • As larvae mature, they become solitary feeders and eventually eat the entire leaf.
  • Larvae are active from late July through early September.
  • They have black heads with striped body covered with fine white hairs and a bright yellow spot behind the head.
  • More information on Yellownecked caterpillar
5 of 6
  • Image: Japanese beetle 1
  • Image: Japanese beetle 2
  • Image: Japanese beetle 3

Japanese beetle
Popillia japonica

  • Skeletonizes leaves, i.e. chews leaf tissue between the veins creating a lacelike appearance
  • Adults are metallic green; bronze wings; white tufts of "hair" along their sides
  • Beetles present as early as late June and are active through September
  • Feeds on 100's of different plant species, including gray birch
  • More information on Japanese beetle
6 of 6
  • Image: Dusky birch sawfly 1
  • Image: Dusky birch sawfly 2
  • Image: Dusky birch sawfly 3

Dusky birch sawfly
Croesus latitarsus

  • Consume leaves as they feed on the leaf margins; larvae feed in groups
  • Fully-developed larvae have black heads with a yellowish or greenish body
  • Preferred hosts are gray birch
  • More information on Dusky birch sawfly

Don't see what you're looking for?