What Is Wrong With My Mountain Mahogany?

Are the leaves curled, distorted, and yellow?

Are there holes in the trunk?

Are there any dark brown streaks on the wood where the bark had separated from the tree, silver or whitish flecks may appear on the inner bark surface?

Are there any sunken areas in the wood of the branch, stem, or trunk that contains dead tissue?

Do the leaves have any small circular or irregularly shaped dry spots which are gray to straw in color?

Are the leaves covered with white powder?

Distorted, curled leaves are caused by aphids. These tiny insects can vary in color, green, pink, black, gray to completely white. They cluster under leaves and on growing tips where they feed on plant sap. Leaves, stems, and buds get distorted, and later leaves and flowers drop from the plant. You can control them by washing them off the plant with water spray. Insecticidal soap should be used with severe infestations.

Adult flathead borers are beetles, flat-looking, and colored metallic brown to a dull gray. They emerge in the spring and females lay eggs in crevices in the tree bark. If the host tree is vigorous and healthy, these burrowing worms may be drowned by the sap. Weak trees fall victim to the borers' activity as they tunnel in the trunk, producing sawdust-like material and eventually girdling the tree. Young almond trees are particularly vulnerable. If the tunnels are fairly straight, kill the borer larva by probing the tunnel with a flexible wire.

Annosus root disease infects the roots or butt of the host tree. May cause extensive root decay and gradual tree death. Bark may separate from the tree, revealing dark brown streaks on the wood beneath. Silver or whitish flecks may appear on the inner bark surface, with small whitish mycelial growths on the outer bark. Avoid wounding trees, as wounds may become infection sites. Borax can be applied to fresh cuts to avoid infection.

Hypoxylon canker is a disease that attacks mahagony trees and shrubs. Prune out and destroy dead branches and infested areas. Be sure to make pruning cuts at least 3 or 4 inches below the canker and disinfect pruners between cuts. Spray both the healthy and diseased sections of a tree with copper during and shortly after periods of excessive rain.

These symptoms indicate a fungal disease - Anthracnose. Keep plants dry when watering to prevent spread. Spray plants with copper when the first fruit develops if you have had problems in the past. Bordeaux mixture can also help to protect the plant from the disease.

White, powdery patches on the leaves are caused by a fungal disease Powdery mildew. Powdery mildew usually appears in damp places. Encourage good air circulation around the affected plants by thining them and any surrounding plants. Water plants from bellow to keep foliage dry. Any affected leaves should be cut off and removed. Appropriate fungicidal spray will protect your plant from further infections.

Heart rot is a fungal disease that may cause problems for mahagony trees and shrubs. This fungal disease enter trees that have been injured by a storm or improper pruning. Once the fungus enters the tree, it slowly rots the wood, weakening and eventually killing the tree. To prevent heart rot, prune the tree regularly to remove branches damaged by ice or wind.