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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Deciduous > Cotoneaster > Rough or bumpy areas on bark

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Cotoneaster > Stems/branches > Rough or bumpy areas on bark

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Oystershell scale
Lepidosaphes ulmi

  • Light to moderate infestations show little or no symptoms
  • Severe infestations can cause chlorotic, stunted foliage
  • Dieback and cracked bark can result from heavy infestations
  • Light to dark brown, elongated, 1/10 to 1/8 inch long oyster-shell shaped scales found on bark
  • More information on Oystershell Scale
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Nectria canker
Nectria cinnabarina

  • Dead branches and twigs, often first observed in early spring
  • Bark at the base of dead branches is slightly sunken, discolored or cracked
  • Tiny, pink, pale orange or cream colored cushion-like spore-producing bodies are visible in cracks in bark in spring
  • In summer, smaller coral colored bumps push through cracks
  • In autumn these spore-producing structures are dark brown or black
  • More information on Nectria canker

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