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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Evergreen Trees and Shrubs > Pine > Sticky substance coating needles

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Pine > Needles > Sticky substance coating needles

1 of 2
  • Pine tortoise scale 1
  • Pine tortoise scale 2
  • Pine tortoise scale 3

Pine tortoise scale
Toumeyella parvicornis

  • Moderate feeding can cause needles to yellow and become shortened
  • Heavy infestations can cause shoots and branches to die back
  • Feeding produces honeydew which can cause sooty mold
  • Individual scales are reddish-brown, helmet-shaped and up to ¼ inch long when mature
  • More information on scale insects
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  • Diplodia shoot blight 1
  • Diplodia shoot blight 2
  • Diplodia shoot blight 3

Diplodia shoot blight
Diplodia pinea

  • New needles are brown, short and often glued together with resin
  • Cankers are resin coated flattened areas on branches
  • Needles and branch beyond canker turn brown and dies
  • Tiny, black, pimple-like fungal structures on dead needles and pine cones
  • Infected shoots and dead branches occur throughout the tree but most commonly in lower canopy
  • Cankers and dead needles can appear rapidly after wounding from hail, drought or other stress
  • Olive to dark brown streaking in sapwood below cankers
  • Common on Austrian, red and Scots pine
  • More information on Diplodia shoot blight

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