How to Treat Apple Tree Cankers
- 1). Prune out all infected tree areas. Use a sharp, clean pruning tool and do not use an infected tool on healthy tree areas or other healthy trees without proper cleaning.
- 2). Cut out the smaller shoots entirely if cankers are on shoots. If cankers occur on larger branches, carve out all the brown infected tree tissues with a sharp knife. The branch is then able to regain its health.
- 3). Burn all pruned, infected tree parts. This minimizes spread of fungal infection.
- 4). Treat infected trees by spraying affected areas with fresh bordeaux mixture at the rate of 10-10-100. Use the treatment during early fall prior to rains.
- 5). Apply fungicide again after the tree has lost three-fourths of its foliage during fall. This is often necessary when trees are seriously infected. Bordeaux is an organic fungicide for treatment of apple canker.
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