Friday, April 1, 2011
Target Canker on Pecan
The canker disease pictured here is commonly called target canker., The target-like concentric rings of callus tissue form as the tree responds to the attacking fungus. The disease is caused by the fungus, Nectria galligena, which seems to infect trees at the site of branch stubs. A large number of cankers weakens the health of a tree and can lead to poor growth and low nut yield. If this tree was in my native grove, it would have been cut down years ago.