Heat Necrosis

High soil and tuber temperatures cause heat necrosis.
It occurs when a period of slow tuber growth is followed by active tuber growth at high temperatures. Light to dark brown necrotic spots or blotches form in the
vascular tissue of the tubers. Cortical tissue between the vascular ring and tuber skin is seldom affected.
There are no external tuber symptoms of heat necrosis.
The varieties Atlantic and Chieftain are very susceptible to heat necrosis.