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Witches Broom


Witches Broom

Usually appear in

All year

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Caused By:-     Various Fungi, bacteria and aphids


Witches broom is an abnormal growth of a many-branched structure and is commonly found on a large number number of species of trees, shrubs and soft plants such as cocoa, maple, Hornbeam, willow, conifers such as pine and spruce, honeysuckle, potatoes and its related Solanum species. The strength and flexibility of the growth on trees was an ideal material for making brooms in olden times. In the past, mysterious and unexplainable events were often blamed on witchcraft often as a result of the growths appearance in Autumn or Spring. Most are caused by Micoplasma, Fungi, and Bacteria which are transmitted by aphids and other leafhoppers. Witches' broom does not kill trees or plants but what it does is to deplete the tree of its nutrients and slow its growth and reduce crops. A heavily infested tree becomes weakened and consequently vulnerable to the attack of other diseases or the effects of weather which can lead to the death of the tree, shrub or plant. Each tree or plant usually has its own fungi, bacteria or aphid that instigates its occurrence. For example in Hornbeam(Carpinus betulus) it is the fungus Taphrina carpini, in birch (Betula pendula) it is the fungus Taphrina Tugida and in honey suckle it is caused by an aphid. Most brooms have a more or less independent existence, despite the fact that they grow from the tissues of the host instead of the normal growth of the plant. Often the buds from witches broom opens several weeks before the normal buds and do not flower. Witch's broom growths on trees can last for many years and can eventually weigh several kilogram with a hard core of wood with a very distorted grain pattern, which was once highly valued by wood turners production of beautifully patterned wooden bowls. Picture from Wikimedia Commons.


Human activity is often the cause of the introduction of these organisms; for example when a person prunes a tree improperly, leaving the tree susceptible to the Micoplasma, Bacteria or fungi. This disease is also readily transmitted by leaf hoppers or aphids. The growths can be contained by pruning infected branches and spraying fungicides containing copper or systemic fungicides in soft plants.

P_witchesbroom P_witchesbroom2

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