Location: McLoud Farms, McBee, SC. Date: February 2010. Powell Smith, Extension Specialist at CU investigated a tree with strange galls underneath buds: Only one major limb from one scaffold was involved; at the junction of this limb and the other major limb of that scaffold was a large, rough 'lump or knot' (I would not describe it as a canker, as no wood was exposed), the bark on the lump was rough, blackened and exfoliating in thick cubical chunks; on that major limb and the other major limb on that scaffold there were smooth knots and lumps that had pushed through the bark but were themselves covered with healthy smooth bark. I cut some of the large secondary limbs to obtain whole limb samples and noted that, in all cut limbs, there was discolored heartwood. It appeared that the tree had a problem with gummosis. A lot of fungi cause 'galls', burls, and various knots and lumps on woody plants; I wonder if this problem has a fungal etiology e.g. Botryosphaeria.
The variety is 'Gala' from a nursery in McMinnville, TN. The block is in its eighth leaf. It is an isolated tree on the row by the road; I walked widening circles out into the block and saw no other symptomatic trees but did not have time to do what I would call a good survey. Although the symptoms were only noticed this year, there have been at least four years that small limbs have emerged from swollen buds. Dr. Walker Miller mentioned that he had seen this symptom one time before in South Carolina.