Skip to Left navigation Skip to Main content Skip to Footer

University of Minnesota Extension

Extension > Garden > Diagnose a problem > What's wrong with my plant? > Deciduous > Serviceberry > Dense clusters of twigs

Print Icon Email Icon Share Icon

Serviceberry > Trunk/branches > Dense clusters of twigs

1 of 1
  • Image: Eastern Tent Caterpillar 1

Black witches' broom
Apiosporina collinsii

  • Witches' brooms, clusters of numerous weak shoots arising from one point on a branch, occur randomly throughout the tree
  • Dark, olive colored spots of fungal fruiting bodies on underside of leaves
  • Leaves within witches' brooms are first yellow and stunted, turn black
  • Common in wooded, shaded and moist areas

Don't see what you're looking for?