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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Deciduous Trees > Oak > Unusual growths on twigs or branches

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Oak > Trunk/Branches > Unusual growths on twigs or branches

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  • Image: Oak bullet gall 1
  • Image: Oak bullet gall 2
  • Image: Oak bullet gall 3

Oak bullet gall
Disholcaspis quercusglobulus

  • Round, acorn-like galls attached to branches that are dark brownish at maturity
  • Sticky honeydew excreted by galls
  • Bur and white oak are preferred hosts
  • More information on Oak bullet gall...
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  • Image: Oak apple gall 1
  • Image: Oak apple gall 2
  • Image: Oak apple gall 3

Oak apple gall
Amphibolips spp.

  • Spherical, smooth growths are dark greenish to brownish and up to 2 inch diameter in size and filled with spongy material
  • Found on leaf stem or vein in middle of leaf
  • Red and black oak are preferred hosts
  • More information on Oak apple gall...
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  • Image: Noxious oak gall 1
  • Image: Noxious oak gall 2
  • Image: Noxious oak gall 3

Noxious oak gall
Neuroterus noxiosus

  • Tuber-like, irregular or potato-shaped growth that is ¼ to 4 inches long on branches
  • Leaves become dwarfed, curled or shriveled
  • Associated with swamp white oak
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  • Image: Phomopsis galls 1
  • Image: Phomopsis galls 2
  • Image: Phomopsis galls 3

Phomopsis galls

  • Galls are round woody balls, occurring individually or clustered on twigs or branches
  • Range in size from 1/4 to 2 inches in diameter
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  • Image: Wool sower gall 1
  • Image: Wool sower gall 2
  • Image: Wool sower gall 3

Wool sower gall
Callirhytis seminator

  • Round spherical gall with fuzzy whitish reddish exterior that browns with age; up to 1 ½ inch diameter
  • White oaks are preferred hosts

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