U of M Gardening Information: What's wrong with my plant?

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Small, 1/8th inch, round exit holes in trunk and branches
Heavily infested trees typically have sparse, yellowed leaves
Premature leaf drop and broken twigs in crown can also occur when heavily infested
Weakened, stressed trees most likely attacked, rarely infest healthy trees
High Hickory bark beetle populations are often associated with Hickory decline
Adults dark brown to black, less than ¼ inch long
More information on Hickory bark beetles...

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Leaves are wilted or undersized, thin canopy with dead branches
When bark is peeled back, numerous reddish brown oval cankers up to 1 ft. long can be seen
Bark surface often shows no symptoms, occasionally cracking or dark sunken area can be seen
Dark bleeding spots that appear in May or June indicate cankers below the bark
Groups of young green shoots (sprouts) often form along the trunk; these wilt and die within a year
Round 1/8th inch exit holes of hickory bark beetles on upper trunk
Larval galleries often visible in discolored sapwood
Trees can decline and die in as little as two years when beetle populations are high

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Credit: Edward L. Barnard, Florida Dept. of Agriculture and Consumer Services, Bugwood.org
Credit: M. Grabowski, University of Minnesota
Credit: M. Grabowski, University of Minnesota
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Leaves are small and may yellow and drop
Canopy appears thin with few leaves and multiple dead branches
Fungal conks, semicircle shelf fungi, can be found from the base of the tree up to 3 feet high on the trunk
Conks are reddish brown and shiny on top, white and porous underneath, a rim of white may be visible on the edge of the growing conks
Infected wood at the base of the tree is white, soft, stringy or spongy
Infected trees frequently break or fall over in storms
More information on Ganoderma root and butt rot...

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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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Canopy may show no symptoms, or may have small, yellowing leaves or dead branches depending on the extent of decay
In cross section, the wood at the center of the trunk is white, mottled, soft and crumbly
Hoof-shaped, silvery-grey to brown, fungal fruiting bodies up to 8 inches across arise along the stem; often near a pruning wound, crack or other wound
More information on Heart rot...

Hickory > Leaves > Canopy is thin with yellow or brown leaves