What's wrong with my plant? : Garden : University of Minnesota Extension

Ironwood (Ostrya) > Branch > Leaves small and discolored yellow to brown

1 of 3

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

2 of 3

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

3 of 3

Dead branches within the canopy
Yellowing to brown leaves may be present
Groups or rows of small (<2 inches wide), thin, semi-circle shelf fungi along killed branches or on the main trunk, often near cracks or wounds
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