Trees - Canker


 

There are two common forms of canker, fungal canker and bacterial canker.

The fungul type is a common and destructive diseases of apple trees, and may also affect pears, beech, ash, poplar, and sorbus.

If left unattended small branches can be girdled and killed in a single season.

The fungus spreads from the edge of the canker during the dormant season and produces spores, these spores are then spread by wind and rain into wounds which were possibly made by woolly aphids.

What happens is: an area of bark dies, and gradually forms a hollow, and the fungus forms at its edges, sometimes resulting in an infection so bad that it can kill whole branches.

In summer, white pustules appear on the sunken bark, these pustules are filled with spores, which when disturbed are spread by wind, these develop into small red bodied spores which remain on the tree throughout the winter months.

Fungal Canker

Heavy, waterlogged soil may aggravate canker.


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