Skip to Main navigation Skip to Left navigation Skip to Main content Skip to Footer

University of Minnesota Extension
www.extension.umn.edu
612-624-1222

Extension > Garden > Diagnose a problem > What's wrong with my plant? > Evergreen Trees and Shrubs > Pine > Dead branches or leader

Print Icon Email Icon Share Icon

Pine > Trunk/Branches > Dead branches or leader

1 of 5
  • 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...
2 of 5
  • White pine weevil 1
  • White pine weevil 2
  • White pine weevil 3

White pine weevil
Pissodes strobi

  • Terminal leader dead or dying, curled into a shepherd's crook
  • Branches in whorls near the top may also wilt and die
  • Repeated attacks can leave trees looking bushy
  • Drops of sap from feeding wounds on terminal shoots in early spring
  • Prefers Eastern white pine but will also infest jack pine and Norway and blue spruce
  • Small, ¼ inch long, white, grub-like larvae feed under bark from June to August
  • Adult weevils ¼ inch long, dark with tan and white mottling; has conspicuous snout
  • More information on White pine weevil...
3 of 5
  • White pine blister rust 1
  • White pine blister rust 2
  • White pine blister rust 3

White pine blister rust
Cronartium ribicola

  • All needles on one or several branches die and turn completely reddish-orange
  • Young cankers are elliptical, bark appears swollen and discolored yellowish orange
  • Older cankers exude large amounts of white sticky resin and have cracked bark
  • In early spring, orange-yellow blisters appear on the bark of cankers that are 2 or more years old
  • In summer, yellow-orange sticky liquid droplets form in cankers 3 years or older
  • Only white pine and other five needled pines can be infected
  • More information on White pine blister rust...
4 of 5
  • Zimmerman pine moth 1
  • Zimmerman pine moth 2
  • Zimmerman pine moth 3

Zimmerman pine moth
Dioryctria zimmermani

  • Dead terminal leader and shoots are common
  • Larvae feed at branch whorls and a base of shoots
  • Pitch mixed with reddish frass just below feeding sites
  • Affected shoots turn brown and may break off
  • Larvae are dark pinkish-green, about ¾ - 1 inch long
5 of 5
  • Pine shoot beetle 1
  • Pine shoot beetle 2
  • Pine shoot beetle 3

Pine shoot beetle
Tomicus piniperda

  • Dying, dead and broken shoots, particularly in the top half of the tree
  • Adults tunnel into shoots which turn yellow to reddish-brown
  • Attacks most pine species where cut stumps or logs are present
  • Adults are shiny, black and about the size of a match head
  • Larvae are white with a brown head and about ¼ inch long
  • More information on Pine shoot beetle...

Don't see what you're looking for?

  • © Regents of the University of Minnesota. All rights reserved.
  • The University of Minnesota is an equal opportunity educator and employer. Privacy