Control
Non-chemical control
Pruning out twigs that are blistered, and disposing of fallen leaves and infected fruit will reduce the amount of the fungus available to start infections in the next growing season. Unfortunately, this can be of limited value unless the trees are isolated, because the spores can be blown for long distances.
Some apple cultivars are resistant to infection, including:
A-C
‘Adam’s Pearmain’, ‘Alfriston’, ‘Ashmead’s Kernal’, ‘Barnack Beauty’, ‘Beauty of Bath’, ‘Brownlees Russet’, ‘Charles Ross’, ‘Cheddar Cross’, ‘Claygate Pearmain’, ‘Cockle Pippin’, ‘Cornish Aromatic’, ‘Cornish Gilliflower’, ‘Court Pendu Plat’, ‘Crawley Beauty’
D-F
‘D’Arcy Spice’, ‘Discovery’, ‘Duke of Devonshire’, ‘Edward the Seventh’, ‘Ellison’s Orange’, ‘Emneth Early’, ‘Encore’, Epicure’, ‘Exeter Cross’
G-L
‘Golden Reinette’, ‘Grenadier’, ‘Ingrid Marie’, ‘John Standish’, ‘King of the Pippins’, ‘King Russet’, ‘Lane’s Prince Albert’, ‘Lord Derby’, ‘Lord Hindlip’
M-Q
‘Melba’, ‘Merton Russet’, ‘Millers Seedling’, ‘Monarch’, ‘Mother’, ‘Newton Wonder’, ‘Orleans Reinette’, ‘Park Farm Pippin’, ‘Pinova’, ‘Ponsford’
R-Z
‘Rajka’, ‘Red Devil’, ‘Reinette du Canada’, ‘Resi’, ‘Reverend W. Wilks’, ‘Rosemary Russet’, ‘Ross Nonpareil’, ‘Rubinola’, ‘Santana’ (but is very susceptible to canker), ‘Stirling Castle’, ‘Suntan’, ‘Tom Putt’, ‘Topaz’, ‘Wagener’, ‘Wealthy’, ‘Wheeler’s Russet’, ‘Winston’, ‘Woolbrook Russet’.
Resistant pears include:
‘Beurre Hardy’, ‘Docteur Jules Guyot’, ‘Fondante d' Automne’, ‘Gorham’, ‘Hessle’, ‘Jargonelle’, ‘Josephine de Malines’, ‘Nouveau Poiteau’, ‘Catillac’, ‘Black Worcester’, ‘Souvenir du Congrès’.
Chemical control
No fungicides are currently being produced for use by home gardeners on trees from which the fruit will be consumed.
Fungicides labelled for use on ornamental plants to control other diseases can be used on ornamental Malus (crabapple) and Pyrus trees (provided the fruit are not intended for consumption) and may provide some incidental control. They are used at the owner’s risk (test-spray a small area first to ensure that plant damage does not occur), but are safe to the operator when used as directed.
For the most effective control, you need to cover the whole tree. Unfortunately, most gardeners will not have sprayers capable of treating large, old trees.
Download
Fungicides for gardeners (Adobe Acrobat pdf document outlining fungicides available to gardeners)
Links
Chemicals: using a sprayer
Chemicals: using safely and effectively
Chemicals: storing and disposing safely