When a tree exhibits mild symptoms, prune out affected limbs and water to maintain tree vigor. The smallest branches may not exhibit the discoloration.ĭo not replant susceptible species where a specimen was killed by Verticillium. The wood under the bark of wilting branches is discolored with green to black streaks. Frequently, the foliage on only one side of a tree wilts. Oval to irregularly shaped, shiny, black spots up to ½ inch in diameter form on the leaves of silver or red maples.Įarly symptoms of verticillium wilt include heavy seed production, leaves that are smaller than normal, and browning of the margins of leaves. No control is necessary since the disease begins too late to cause significant damage. White fungal growth develops on the upper surface of leaves in the late summer and autumn. Tiny, black fungal fruiting structures dot the upper surface of the spots. Leaf spots up to 1/4 inch in diameter with a pronounced purple border are round or irregular in shape. Infected trees are very prone to wind breakage even before the fungus begins to form fruiting structures and should be removed at the first sign of infection. Laetiporus sulfureus (formerly Polyporus sulfureus)įruiting structures form long after most of the damage has been done. The bark where the fruiting structure forms is slightly depressed and cracked. New shelves form on the wood the following summer and autumn. The underside of the fruiting structure has tiny pores in which the spores are formed. Massive clusters of bright sulfur-yellow to salmon to bright-orange, shelf-like fruiting structures that turn white with age initially form in the summer or autumn on the wood of the tree but fall off during the winter. Branches and eventually the entire tree die as the root rotting progresses.Ī tree with fungal fruiting structures on the trunk, butt, or roots should be removed promptly if it is in a location where property damage may occur or where people or pets could be struck by falling limbs or the falling tree. The upper surface may appear to have been varnished. They are brown to reddish brown on top with a cream to white margin, and may reach 14 inches across. Very distinctive shelf-like fruiting structures form annually on the wood singly or in overlapping clusters. Heart rot and dying limbs may be apparent.Ī tree with fungal fruiting structures on the trunk should be removed promptly if it is in a location where property damage may occur or where people or pets could be struck by falling limbs or the falling tree. The underside of the "hoof" is white with tiny pores in which the spores are formed. Protect the tree from stresses, particularly insect defoliation.Ī fungal fruiting structure that is hard, gray topped, hoof shaped, and 6 to 8 inches across and enlarges perennially. Branch dieback progresses until much of the tree is dead.ĭepending upon the site, combinations of poor soil aeration, poor soil drainage, deicing salt damage, high temperatures at the site, drought, excavation damage, soil compaction, paving close to trees, verticillium wilt, and armillaria root rot weaken and kill the tree. Remove the infected tree and do not replace it with a woody ornamental until the soil has been fumigated and aerated thoroughly. The bark over the canker becomes sunken, and reddish-brown sap oozes out.
Reddish-brown cankers develop in the inner bark of the main trunk and branches. Promote plant vigor by protecting the tree from stresses. Leafhoppers and spittle bugs carry the bacteria from tree to tree. The light-brown area is separated from green tissue by a dark reddish-brown band and a narrow but distinct yellow halo. Leaf margins on localized, individual branches brown in mid- to late July. In a nursery situation, apply a fungicidel at bud break and at 7- to 10-day intervals until the weather dries and the daily average temperature is above 65☏. Usually, little damage occurs and no treatment is necessary. Under very wet spring conditions, some defoliation can occur. Small, brown fruiting structures of the fungus are found near the affected leaf veins.
Sugar maple: large, irregular, brown or red-brown areas develop along and between the veins similar to injury due to drought and heat stress. Norway maple: narrrow, purple to brown streaks occur along the leaf veins.
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