Healthy trees are a cornerstone of any vibrant garden, but they can face challenges from a variety of pests and diseases. Early detection is vital to safeguarding their health. Here’s a guide to some of the most common threats to trees in the UK, with tips on how to spot the warning signs and take action.
1. Aphids (Greenfly, Blackfly, Woolly Aphids)
Symptoms: Look for distorted or yellowing leaves, sticky residue (honeydew), and the presence of sooty mould. Woolly aphids also leave fluffy white deposits on branches.
Commonly Affected Trees:
Ornamental Cherry (Prunus species)
Apple Trees (Malus species)
Prevention and Treatment: Encourage natural predators like ladybirds or spray with horticultural soap. Prune out heavily infested branches.
2. Horse Chestnut Leaf Miner
Symptoms: Brown blotches on leaves that look scorched, often leading to early leaf drop.
Commonly Affected Tree:
Horse Chestnut (Aesculus hippocastanum)
Prevention and Treatment: Remove and dispose of fallen leaves to disrupt the pest's life cycle. Pheromone traps may help in severe cases.
3. Ash Dieback (Hymenoscyphus fraxineus)
Symptoms: Wilting leaves, blackened stems, and lesions where branches join the trunk. Trees often die back from the crown.
Commonly Affected Tree:
Ash (Fraxinus excelsior)
Prevention and Treatment: Currently no cure exists. Monitor trees closely and consult an arborist for advice on removal to prevent spread.
4. Oak Processionary Moth (OPM)
Symptoms: Caterpillars with distinctive long white hairs cause defoliation, weakening the tree. They can also pose health risks to humans and pets due to their toxic hairs.
Commonly Affected Tree:
Oak (Quercus species)
Prevention and Treatment: Report sightings to the Forestry Commission. Avoid handling caterpillars and seek professional removal.
5. Honey Fungus (Armillaria)
Symptoms: Affected trees may show decayed roots, white fungal growth under the bark, and clusters of honey-coloured mushrooms near the base. Leaves wilt and branches die-back.
Commonly Affected Trees:
Apple Trees (Malus species)
Birch (Betula species)
Prevention and Treatment: Remove and destroy infected roots. Use physical barriers like root collars to prevent spread.
6. Phytophthora Root Rot
Symptoms: Wilting leaves, poor growth, and dark, mushy roots. The disease thrives in waterlogged conditions.
Commonly Affected Trees:
Beech (Fagus sylvatica)
Yew (Taxus baccata)
Prevention and Treatment: Improve drainage around trees and avoid planting in poorly drained soils.
7. Powdery Mildew
Symptoms: A white, powdery coating on leaves, often leading to leaf curling and stunted growth.
Commonly Affected Trees:
Sycamore (Acer pseudoplatanus)
Crab Apple (Malus species)
Prevention and Treatment: Ensure good air circulation by pruning overcrowded branches. Apply fungicidal sprays during the growing season if necessary.
8. Red Spider Mites
Symptoms: Fine webbing on leaves and yellow speckling, particularly during dry, hot summers.
Commonly Affected Trees:
Plum (Prunus domestica)
Citrus Trees
Prevention and Treatment: Increase humidity around the tree by misting leaves. Introduce predatory mites as a natural control.
Protect Your Trees with Bowhayes Trees
At Bowhayes Trees, we’re here to help you plant and maintain healthy trees. Browse our range of resilient native and ornamental species at www.bowhayestrees.co.uk. Whether you’re adding to your garden or seeking advice on pest and disease management, we’ve got you covered.
Comments