Oak Bracket Fungus Description: The surface is a creamy brown color with pitted tubes that secrete an orange/amber liquid when young. The underside is filled with fine pores that are grey/white in color, eventually becoming yellow with age. The conks darken with further age, becoming dark brown or black.
Applying a benomyl-containing fungicide keeps high-value trees free of the fungus. Use a wetting agent with the fungicide to improve coverage of the waxy leaf surface. All species of oaks are susceptible, but young red oak trees are the most severely damaged. Small, distinct reddish brown spots form on diseased leaves.
The catkins will begin to fall in the early spring when the weather starts to warm up. They'll typically take about two or three weeks, depending on the local conditions.
The disease eventually spreads to the leaf veins, discoloring them and forming small, black fruiting bodies that contain fungal spores. These spores are the primary source of infection, spreading through rain and wind. Leaves will eventually brown starting from the tips of the leaves, creating wedge-shaped necrosis.
Oak wilt's initial signs often manifest in the leaves. Look for wilting and browning, starting from the leaf margins and progressing inward in a characteristic V-shaped pattern. As the disease advances, affected trees rapidly shed their leaves, resembling the appearance of a premature autumn.
Infected trees and their roots will usually die before root grafts can be re-established. The oak wilt fungus does not survive in the root systems of dead trees for more than a few years. The potential for spread of oak wilt through grafted roots is especially high after a diseased tree is removed or dies.
If the layer of catkins is less than an inch thick, try mowing. If it mostly disappears with mowing, there is no need to remove it. If, however, the grass is covered with a layer over an inch thick and is completely buried, rake up what you practically can and put it into beds as mulch or put it in your compost pile.
The trees are dropping male catkins, which carry the male flowers of the tree. Use them as mulch or throw them in the compost when they start to pile up.
Male flowers, or catkins, look like long worms hanging from the oak tree during spring. After the stamens release pollen into the air, the catkins fall to the ground. The pollen hangs mist-like in the air before descending onto the female flowers and fertilizing them.
One diagnostic sign of Armillaria root rot is the white fan-shaped mycelia, thin, flat sheets of fungal tissue (mycelial fans) that grow just below the bark. To find these mycelial fans, select a dead or dying plant to examine.
In yard settings where healthy oaks are extremely valuable to homeowners, and nearby oaks have oak wilt, homeowners may consider hiring an experienced, professional arborist to inject their healthy red or bur oaks with a fungicide containing propiconazole.
These mites are nearly invisible to the naked eye, measuring about 0.2 millimeters, yet their bites can cause significant discomfort. Oak mites are most active during late summer and early fall, coinciding with the lifecycle of their prey, which includes larvae from gall-producing insects.
Phytophthora ramorum. Phytophthora ramorum is an invasive plant pathogen that causes sudden oak death, ramorum blight, ramorum dieback, and Phytophthora canker diseases. There is no cure for the diseases caused by P. ramorum.
These trees prefer an organic soil. Organic fertilizers, like manure or compost, can be used with great success. This material should be worked into the open soil at a rate of one bushel per 1″ of trunk caliper or 100 square feet of bed area.
Oak Leaf Blister
The lower surface has gray depressions that correspond to the raised blisters. As the disease progresses, the blisters turn brown and the leaf will curl as the blisters coalesce. Premature leaf drop also may occur. Trees are not severely damaged, but the appearance of the tree may be unsightly.
The yellowish-beige, wormlike danglers that are by now mostly on the ground are called catkins, more technically known as aments. They are the male flower parts. Each of the little bumps on these catkins is a male flower consisting of a bract (a highly modified leaf), a lobed calyx and some pollen-producing stamens.
Despite their common name, young oakworms are not wormlike but are small, yellowish green caterpillars with large, brown heads and dark stripes on their sides. Older caterpillars vary in color, commonly dark with prominent, lengthwise yellow or olive stripes.
The catkins (a collection of inconspicuous flowers) produced by oaks are fine to use in your garden as a mulch.
These are large (1- to 2-inch diameter) rounded growths that are filled with a spongy mass. A single wasp larva is located in a hard seed-like cell in the center. Galls are usually found on the petioles or midribs of leaves. They will dry to a brown, paper thin wall.
Appearance: Catkins appear less densely packed than those on other trees. Male catkins are yellow, each around 6cm long and grow in rows, hanging down from the branch in a curtain. The female flowers are tiny and red, with fine filaments protruding to catch the pollen.
Cutting down a tree with oak wilt that is still partially alive can cause the disease to spread, but removing it during the least vulnerable months can prevent this.
Vertical cracks, seams, dead branch stubs and large, older wounds suggest internal decay. Severe damage to the main trunk often warrants removal of the tree. If the damaged area is less than 25 percent of the circumference of the trunk, the wound could gradually heal over and no permanent injury should result.