
Beech Leaf Disease & Management Options*
Quick Facts
- Beech leaf disease (BLD) is a new disease to the United States; scientists have been working quickly to understand its pathogenesis and test treatment options to mitigate or control damage.
- BLD affects beech (Fagus spp.) tree species and has not been shown to infect any other genera. This disease poses no direct harm to humans.
- BLD causes rapid decline and mortality of American beech (Fagus grandifolia) and European beech (F. sylvatica); mortality can occur between 2 to 10 years depending on size. BLD has also been reported to impact Oriental beech (F. orientalis) and Chinese beech (F. engleriana).
- BLD is caused by an invasive nematode Litylenchus crenatae subsp. mccannii (Lcm; Figure 1). A nematode is a microscopic roundworm that cannot be seen with the naked eye.
- BLD is recognized best by opaque banding of diseased leaf tissue (Figure 2).
- Infection occurs in the leaf buds. Lcm does not infect woody tissue.
- Primary damage to leaf tissue occurs in the bud stage.
- Highly infected and damaged leaves become thickened, distorted, prematurely shed, and branch dieback ensues. Decline and mortality follow.
- Thiabendazole, the active ingredient in Arbotect 20-S, is currently the most effective treatment option. Proper application is key to high efficacy and beech health; refer to the Arboricultural Treatment section.
- When treatment is not an option, mitigation steps are key to reducing negative environmental impacts from beech losses.
*Our neighbor Doris Wait sent us information from Rutgers University that is excerpted above. The full Bulletin can be found at: njaes.rutgers.edu/E376/
Some local businesses that can provide information &/or treatment are: Arborist Enterprises, Tomlinson-Bomberger, Bartlett and others.