Frequently Asked Questions About Beech Leaf Disease (BLD) and Tree Care
Below are answers from our arborist about common questions.
Beech Leaf Disease is caused by a microscopic nematode (Litylenchus crenatae mccannii) that damages buds and leaves, leading to dark leaf banding, canopy thinning, and eventual decline or death of beech trees.
Since its discovery in 2012 in Ohio, BLD has been detected in at least 15 U.S. states—including Delaware, Pennsylvania, and Maryland—as well as in Ontario, Canada.
Common signs include:
- Dark green or yellowish bands between leaf veins
- Curling, puckering, or leathery leaves
- Premature leaf drop
- Buds that fail to open in spring
- Twig and branch dieback
BLD impacts native American beech (Fagus grandifolia), European beech (Fagus sylvatica), and Oriental beech (Fagus orientalis).
No cure exists at this time. However, research-based treatments and good cultural care can help slow disease progression and improve tree resilience.
Penn State Extension notes there is no permanent cure but reports that phosphite fertilizers may help improve a tree’s vitality and could suppress nematode activity. They also encourage regular monitoring and reporting of suspected cases.
Research trials have shown that:
- Arbotect 20-S (thiabendazole) trunk injections can reduce nematode levels in some cases.
- Fluopyram-based applications have lowered nematode counts in ornamental settings.
- Potassium phosphite bark sprays can reduce leaf symptoms, defoliation, and twig dieback.
These should be combined with overall Plant Health Care practices for best results.
Young saplings may die within 2–5 years, while mature trees decline more slowly but are still at long-term risk.
Not necessarily. Some trees may respond well to treatments, and others may show natural resistance. Consult a certified arborist before removing any tree.
Prevention is challenging due to the nematode’s ease of spread, but early detection and cultural management can help reduce impact.
PHC is a proactive, holistic approach to maintaining tree and shrub health. It includes monitoring for pests and diseases, improving soil conditions, and applying targeted treatments when needed.
At least once a year is recommended, especially if you have mature trees or live in an area where pests or diseases like BLD are active.
Our PHC programs include disease and pest management, deep-root fertilization, structural pruning, tree risk assessments, soil care, and safe tree removal when necessary.
Certified arborists have the training, experience, and credentials to accurately diagnose problems, recommend effective treatments, and ensure tree work is done safely and to industry standards.
