Apple Scab (Venturia inaequalis)

apple scab.jpg (28625 bytes)Common Name(s): Apple Scab

Scientific Name(s): Venturia inaequalis

Type: Fungal

Principle Host Trees & Shrubs:

Malus (Apple), Pyrus (Pear), Sorbus (Rowan), Populus (Poplar), Salix (Willow).

Very common on ornamental Crab Apples.

Description, Development & Diagnosis:

Leaves appear to have olive-green/brown spots and blotches. Diseased leaves can become yellow and black. Leaves (on Apple) fall prematurely throughout Summer. Similar symptoms appear on fruit.

Outbreaks normally follow cool, wet weather.

Fungus overwinters on fallen leaves and within shoot lesions. During the Spring, spores infect new young leaves to complete cycle.


Very common and disfiguring. Can produce a tree of very poor appearance. Tree suffers through loss of photosynthesis.


Treat frequently throughout the growing season with fungicide spray. Remove fallen leaves in Autumn.

Fungicide spray should contain Carbendazim, Mancozeb or Bupirimate with Triforine. Most garden centres should stock fungicide specifically labelled to treat Apple Scab.

Crab Apple - Consider replacement with resistant variety.

Please Note: Many Fungi are toxic and individual reactions to them vary widely. Do not touch or eat fungi unless you have accurately identified them. Chris Skellern can not accept any legal responsibility or liability for errors in identification or for individual reactions to the consumption of fungi.

Further Information.

2001 Chris Skellern. AIE.    Home  | News | A-Z Index  | Resources  |  Contact AIE  |  Terms of Use