Identifying Problems
Before They Spread.

Ash Dieback (Hymenoscyphus fraxineus)

Ash Dieback is now widespread across the UK, including throughout Kent and South East London. The fungal disease causes progressive die-back of the canopy, lesions on bark and stems, and eventual death of the tree, typically within 3–5 years of infection in mature specimens.

Infected ash trees lose structural integrity rapidly and become hazardous to people and property. As a landowner, you have a legal obligation to manage trees that pose a risk to the public. We assess ash trees for infection, advise on management options (which range from monitoring to phased removal), and carry out felling and timber recovery where required.

Symptoms to look for: wilting or blackened leaves in summer, diamond-shaped lesions on bark, die-back from branch tips inward, white fungal bodies at leaf bases in autumn.

Oak Processionary Moth (Thaumetopoea processionea)

Oak Processionary Moth (OPM) is an invasive pest established across much of London and the surrounding counties. The caterpillars defoliate oak trees in late spring and early summer, and their white silken nests, typically visible on trunks and main branches from late April, contain microscopic hairs that cause serious skin, eye and respiratory irritation in people and animals.

OPM nests should not be disturbed or approached without proper protective equipment. If you suspect OPM on your trees, do not attempt to remove the nests yourself. We can assess your oaks and advise on management, which in some cases involves working with the Forestry Commission and your local authority.

Honey Fungus (Armillaria species)

Honey Fungus is the most destructive tree pathogen in the UK. It spreads through soil via rhizomorphs (black bootlace-like structures), attacking the roots and basal stem of a wide range of trees and woody plants. Infected trees can die suddenly, often without obvious above-ground symptoms until late in the infection.

There is no chemical control for established Honey Fungus. Management involves removing infected material, improving drainage, and selecting resistant species for replanting. We can identify the pathogen, advise on removal of infected stumps and roots, and recommend appropriate replacement planting.

Other Common Diseases

• Phytophthora root rot

  Water mould affecting beech, alder and others. Associated with waterlogged or compacted soils.

• Dutch Elm Disease

  Fungal disease spread by elm bark beetles, still present in isolated populations in the South East.

• Sudden Oak Death (Phytophthora ramorum)

  Notifiable disease: must be reported to the Forestry Commission if confirmed.

• Bleeding canker of Horse Chestnut

  Widespread across the region, causing weeping bark lesions and progressive crown die-back.