Eastern Filbert Blight: Understanding and Managing the Disease

Do you have a filbert tree in your backyard or orchard? Are you worried about Eastern Filbert Blight (EFB)? If yes, then this article is for you. EFB is a serious fungal disease that affects hazelnut trees (also known as filbert trees). In this article, we will discuss the symptoms, causes, and management strategies of EFB.

What is Eastern Filbert Blight?

Eastern Filbert Blight (EFB) is a fungal disease caused by Anisogramma anomala. This fungus infects hazelnut trees during the spring when new shoots emerge. The infection starts at the tips of the shoots and moves downward, causing twig dieback and cankers. EFB can also cause defoliation, reduced nut size, and yield loss.

Symptoms of Eastern Filbert Blight

The symptoms of EFB vary depending on the severity of the infection. Early symptoms include small, reddish-brown spots on the leaves and twigs. As the infection progresses, the spots enlarge and become sunken. Infected leaves may curl, wilt, and drop prematurely. Twig dieback and canker formation are also common symptoms of EFB. Cankers are dark brown to black and may ooze sap in wet weather.

Causes of Eastern Filbert Blight

EFB is caused by the fungal pathogen Anisogramma anomala. The fungus overwinters in infected twigs and produces spores during the spring. The spores are carried by wind and rain to new growth, where they infect the shoots and leaves. The fungus can also spread through infected pruning tools and equipment. Hazelnut trees that are stressed or weakened by other factors, such as drought or insect damage, are more susceptible to EFB.

Management Strategies for Eastern Filbert Blight

The management of EFB involves a combination of cultural, chemical, and biological strategies. Here are some ways to control the disease:

Cultural Strategies

• Plant resistant varieties: Choose cultivars that are resistant to EFB, such as 'Jefferson' and 'Yamhill.'
• Prune regularly: Remove infected twigs and cankers during the dormant season. Sterilize pruning tools between cuts to prevent spreading the disease.
• Avoid overhead irrigation: Use drip or furrow irrigation to avoid wetting the foliage and spreading the disease.

Chemical Strategies

• Fungicides: Apply fungicides during the bud break, shoot growth, and nut development stages. Follow label instructions carefully, and apply before rain or irrigation to ensure good coverage.
• Copper sprays: Copper-based fungicides can be used as a preventative measure to protect new growth from infection.

Biological Strategies

• Biocontrol agents: Certain beneficial microorganisms, such as Bacillus subtilis, can suppress the growth of the EFB fungus.
• Natural enemies: Predatory mites and insects, such as lacewings and ladybugs, can feed on the EFB fungus and reduce its population.

Educating yourself about Eastern Filbert Blight is the first step towards managing the disease effectively. By following the cultural, chemical, and biological strategies discussed in this article, you can minimize the impact of EFB on your hazelnut trees. Remember to choose resistant cultivars, prune regularly, and use integrated pest management practices to keep your trees healthy and productive.

A healthy hazelnut tree

Hazelnut, filbert blight, disease management, plant pathology, cultural practices, fungicides, biocontrol agents