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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Deciduous > Ironwood (Ostrya) > Dead twigs or branches

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Ironwood (Ostrya) > Trunk/branches > Dead twigs or branches

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  • Image: Codling moth 1
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Armillaria root rot
Armillaria spp.

  • Infected trees have poor growth, dead branches in the upper canopy, undersized and/or yellow leaves
  • Flat white sheets of fungal growth (mycelial fans) between the bark and sapwood at the base of infected trees
  • Thick black, shoestring-like fungus can sometimes be seen under the bark, around roots and in the soil around the base of the tree
  • Wood is decayed, white, soft and spongy; this may extend from the base of the tree well up into the trunk
  • Trees frequently break or fall over in storms
  • Clusters of honey-colored mushrooms may grow at the base of the tree in fall
  • More information on Armillaria root rot
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  • Image: Fruitworms 1
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Twolined chestnut borer
Agrilus bilineatus

  • Leaves in upper canopy turn brown and dead branches are present
  • Damage visible mid to late summer
  • S-shaped galleries beneath bark
  • 1/8 inch D-shaped exit holes may be visible
  • Adult has bluish black body with two light stripes running down the wing covers
  • Larvae are approx. 1 inch long and white with 2 spines at the abdomen tip
  • More information on Twolined chestnut borer
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  • Image: Apple Curculio 1
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Apiosporopsis carpinea

  • Leaves have reddish brown irregular spots or blotches
  • Leaves may drop prematurely
  • Reddish brown cankers on branches; may become sunken and surrounded by ridges of wound wood with age
  • Dead twigs and wilted, bleached leaves on branches with girdling cankers
  • More information on Anthracnose
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  • Image: Apple Curculio 1
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Sapwood rot
Cerrena unicolor

  • Dead branches within the canopy
  • Yellowing to brown leaves may be present
  • Groups or rows of small (
  • Shelf fungi are white to greenish gray and have concentric rings on the surface
  • Wood below fungal shelves is yellowish to white, spongy, crumbly and decayed
  • Bark around fungal shelves is killed and often falls off
  • Common on trees stressed by drought, winter injury, wounds, mechanical injury or other factors
  • More information on Heart rot
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  • Image: Apple Curculio 1
  • Image: Apple Curculio 2
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Heart rot
Phellinus spp. and Oxyporus populinus

  • Fungal fruiting bodies arise along the stem, near a pruning wound, crack or other wound
  • Phellinus fungi grow are up to 8" across, hoof-shaped and dark gray above, tan below with a white margin
  • Oxyporus shelf fungi are 6" across, almost as thick and often covered with green moss
  • The canopy may show no symptoms or may have small yellowing leaves or dead branches depending on the extent of the trunk decay
  • In cross section of the trunk, the wood at the center is discolored, soft, crumbling, stringy or spongy
  • More information on heart rot

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