Although the ash has adapted to numerous environmental influences such as dry periods or persistent frost, it is still very susceptible to pest infestation. Not only the dreaded ash dieback but also parasites and beetles cause serious damage to the deciduous tree, which is of great importance for forestry. But these pests are also a nuisance in your own garden and should be combated as soon as possible after detection. This article shows how you can recognize an infestation, what type of pest it is and how you can tackle the unwanted guests.
Some pests leave marks on the bark
Common ash pests
- the ash bark beetle
- the weasel moth
- the ash gall mite
- the ash leaf sucker
- aphids
- the ash weevil
The ash bark beetle
The ash bark beetle, around 3 mm in size, nests in the bark of young or weakened deciduous trees and eats through the wood. Beginning in the crown, its passages later also run through the trunk of the ash tree, so that it gradually dies. The pest is mainly active in the period from March to May.
The weasel moth
The ash weasel moth only infests the ash tree. The first generation, which you can recognize by pitting of the leaves, is followed by a second that also burrows into the terminal buds. There is little danger to the health of the ash, but an infestation reduces the value of the wood, as the growth form becomes crooked.
The ash gall mite
Are you enjoying the blossoms of your ash tree or even hoping to get seeds to propagate the tree? In this case, you should act as soon as possible if you notice initially green, later brown growths on the branches of your tree. The ash gall mite does not kill the ash tree, but it does cause stunted bud sites and reduced seed yield.
The ash leaf sucker
Growths similar to those of the ash gall mite also form when the ash leaf sucker is infested. However, the symptoms appear on the leaves.
aphids
Aphids also cause the leaves to curl up.
The ash weevil
Holey leaves indicate the ash weevil. This is a gray-brown pest that lays its eggs on the underside of leaves in spring.
Note: Pests such as the ash jewel beetle or the false white stalked beetle are not yet widespread in Europe, but are threatening to come closer. Their occurrence would have massive consequences for forestry.
treatment
- be sure to remove all affected shoots
- full pruning may be required
- treat your ash with biological pesticides
- resort to chemical fungicides only in extreme emergencies
- Find out about the seasons when the pests are more prevalent
- check your ash tree regularly for symptoms