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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Deciduous Trees > Hackberry > Growths or bumps on trunk/branches

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Hackberry > Branches/Trunk > Growths/bumps on trunk/branches

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  • Image: Lichens 1
  • Image: Lichens 2
  • Image: Lichens 3

Several species

  • Colorful patches on the bark of trunk and/or branches
  • Can be wrinkled, in scalloped sheets, lace-like pads, bushy tufts, paint-like spots or splashes
  • Forms can be flat against the bark surface or raised in leaf-like lobes, finger-like or hairy projections
  • Colors may be shades of gray, green, blue, yellow, orange, or red
  • Lichens do not harm trees or shrubs and no management is necessary
  • More information on Lichens
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  • Image: Cottony maple scale 1
  • Image: Cottony maple scale 2
  • Image: Cottony maple scale 3

Cottony maple scale
Pulvinaria innumerabilis

  • White marshmallow egg-sacs along the twigs and small branches
  • Young insects remove sap from leaves creating a speckled appearance and possibly yellowing leaves in mid to late summer
  • Honeydew, a sticky, shiny material, on leaves and branches
  • Sooty mold may result from honeydew
  • Heavy infestations cause premature leaf drop and branch dieback
  • Nymphs are brown-translucent, 1/5 inch long
  • More information on Cottony maple scale

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