How to Rid Canker on Apple Trees
- 1). Stop what caused the canker to set in initially. The disease feeds on weakened trees, many of which get too much or not enough water. If there's been a dry spell, increase the amount of water. However, if there's been a lot of rain, don't keep giving it so much water that it floods the roots.
- 2). Remove all branches that have been infected with canker. Cut off each branch as close to the trunk as you can, going through it with a straight cut. Canker thrives on loose ends sticking out here and there.
- 3). Pry off all bark that has been infected with canker using your knife. The infected bark is acting as protection to the canker, and by removing it, the canker will begin to dry out.
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