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Beech Bark Disease

Beech Bark Disease


Most beech tree diseases are caused by fungal infections. These can be prevented if the symptoms are spotted early. You can use the following information to identify common beach tree diseases and choose the suitable form of disease control.

Beech Scale Disease

The beech scale or the Cryptococcus insect is one of the most destructive garden pests. It is an intensive feeder and is known to cause death of young, beech trees. The beech scale itself doesn't cause the Scale Disease. It weakens the tree, making it vulnerable to fungal infections that quickly exhaust the tree’s vigor. This condition of scale-weakened beech trees suffering from fungal infestations is called the Beech Scale Disease. The Nectria family of fungus is known to attack beech trees weakened by scale attacks.

Beech Scale Symptoms

The beech scale is most active on the tree’s bark. It feeds incessantly by inserting its sharp mouthpart into the bark. Due to intensive, night-long feeding sessions, small canker-like spots start appearing on the bark. Due to repeated feeding from the same site, some spots develop a fissure-like appearance. Such fissures eventually become the breeding site for Nectria fungus attacks. These fissures can be identified by a typical white-colored outer edge. This gives the bark’s surface, a wax-coated appearance. A confirmatory indication of fungal infection seeping through the bruised stem sites is the presence of red-colored fruiting bodies called perithecia. Appearance of clustered peritheciae means that scale insect population is declining and the fungal infection is quickly spreading. Fungal infection also causes thinning of the foliage and bending of young stems.

Beech Scale Control

You should understand that most scale-affected beech trees eventually die. Therefore, developing a comprehensive disease management regimen is critical. Use of high-pressure fungal sprays is recommended. You should spray the fungal spray all over the tree’s foliage and the main bark. Every form of diseased foliage should be pruned-off. To limit the entry of fungal pathogens through bruised sites, use oil preparations. You can use horticultural oils. Prepare a mixture of water, horticultural oils and insecticidal soaps. This mixture should be regularly sprayed on all sites suspected of scale attacks. Horticultural oil sprays should be used repeatedly from November to March to kill dormant scales. The oil layer protects against fungal seepage and kills the scale’s eggs. You should prune-away thick, intertwining foliage that often harbors scale colonies. For scale removal, use insecticides that have a high Neonicotinoid concentration. This chemical is known to be effective in killing the feeding, scale larvae. 

Beech Tree Mildew

Powdery Mildew is a common fungal infection among garden plants. Among beech trees, the mildew is concentrated on the basal foliage and young branches.

Mildew Symptoms

An easy-to-sight symptom of mildew development is the presence of white, powder-like, dusted appearance of the leaves.

Mildew Prevention

Maintaining air circulation in tree’s foliage is vital to prevent mildew. Ensure that the beech tree is not overcrowded by surrounding shrubs. Prune-away branches that have split excessively, particularly those close to the tree’s base. Avoid using fertilizers that are nitrogen-heavy and avoid fertilizing intensively during wet conditions.


​Maine Forestry

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