There’s something spooky about this unsightly disease!
When trees are bare in winter, the disorder known as witches’ brooms reveals itself.
Brooms are large clusters of closely growing, many-branched twigs in the crowns of trees, and when you spot the disease in evidence, you’ll quickly realise where it got its name! Sometimes brooms occur scattered on side branches, with ten or more
individual brooms on each tree. Or one enormous broom can form, which may be spherical or elongated and look like an old-fashioned besom. They grow in size and can take over the crown of the tree.
Witches brooms are commonest on birches but are also seen on plums, ornamental cherries, hornbeams and different kinds of conifer. The foliage on brooms is usually abnormal too – leaves are small and leathery, while conifers have short, stunted needles.
The commonest causes are fungi and bacteria, although viruses can produce similar effects. Insects, mites and even eelworms can also bring about superficially similar symptoms.
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