SILOAM ORCHARDS FRUIT TREE FOCUS
APPLE SCAB
Apple scab is the most prevalent disease affecting apple trees. Black spots appear on the foliage in the spring and spread to the fruit. This fungus disease is more active in wet seasons than dry.
This disease , as is the case of most pathogens, will slow the growth of the tree, weaken it, make it more susceptible to winter injury and will damage the fruit perhaps to the point of rendering it unusable.
Commercial orchardists begin protecting their trees from scab as soon as green tissue emerges in the spring. Home gardeners who wish to protect their trees should apply at least one fungicide spray prior to bloom. Many garden centres carry suitable products such as Wilsons Fruit Tree Spray or lime sulfur.Always use these products according to directions. Remember that a " natural " or "organic" label does not mean that a product can be used without necessary precautions and common sense.
Be sure to clean up fallen fruit and leaves in the fall to lessen the supply of apple scab spores overwintering on the orchard floor.
If you are planting new apple trees consider the DISEASE RESISTANT APPLES available from SILOAM ORCHARDS.
Visit these web pages for detailed information on apple scab.
Omafra Factsheet - PRECAUTIONS WITH ALL PESTICIDES
Omafra Factsheet - APPLE SCAB STRATEGY FOR 1998
UNIVERSITY OF WEST VIRGINIA - info page with photos
PENN STATE FACTSHEET WITH PHOTOS
OHIO STATE FACTSHEET WITH PHOTOS