Host of the month - Beech

‘Host of the month’ is a series of Blogs and PDF’s that highlight a tree host and their associated priority pests and diseases that are best seen and recorded in that month. For July we’re looking at Beech (Fagus sylvatica) and Beech leaf disease.

Common Beech is classed as native to southern England and is frequent in places such as the Chilterns but has been planted and is naturalised across much of the UK. It is grown for forestry, the good quality timber finding uses from musical instruments and furniture to the sticks in ice lollies. It’s also a popular choice as an amenity tree with several common cultivars; copper beech, the fastigiate beech ‘Dawyck’, and fern leaved beech with finely cut leaves. It’s most common appearance in gardens though is as hedging, probably in part due to the phenomenon of marcescence where dead leaves are retained on the twigs over winter. The tallest hedge in the world at Meikleour in Scotland is composed of beech and is currently 30m tall!

Priority disease – beech leaf disease (BLD)

BLD was first observed in American beech (F. grandifolia) in Ohio in 2012 and soon spread to other parts of the Eastern USA including Pennsylvania, New York, New Jersey and West Virginia and Ontario in Canada. Research suggests a strong association between the presence of the nematode (Litylenchus crenatae mccannii) and the symptoms of BLD, but it has also been found in symptom-free buds and leaves. American beech is the main species affected, but symptoms have also been reported on common beech and Oriental beech (F. orientalis) planted in the USA. However, as a relatively new disease the full risk to other beech species in not yet known. BLD has not yet been observed in the UK or the rest of Europe but the importance of beech trees and the potential threat to them led to it being added to the UK Plant Health Risk Register.

Identification

The first sign of BLD and a key diagnostic feature is the appearance of dark bands between the lateral veins on the leaves in early summer, conveniently best observed from below. Note that the individual dark bands do not cross the lateral veins. The banded areas gradually take on a leathery texture, frequently accompanied by chlorosis giving a yellow appearance. Over the ensuing few years the canopy begins to thin due to buds being aborted, leaf size reduces, and leaves start to drop prematurely. Saplings displaying symptoms are usually killed within five years, and larger trees within ten.

For more information check the Observatree resource pages for Beech leaf disease, or the Host of the Month for July. You can also test your knowledge with the Host of the Month Quiz.

Reporting

July is an ideal time to seek out Beech trees and see if you can identify any of the signs and symptoms of Beech leaf disease. BLD is a priority disease so please report possible sightings via TreeAlert. Healthy tree data is equally important so please do report those too.