Cabbage diseases are the chief limiting factor In profitable commerclal cabbage growing In Iowa. The most destructive of these are black·leg, black-rot, and cabbage yellows. Any one may destroy the greater portion of a crop. The first two are known to be distributed with the seed and cause Infection of the young plants In the seed bed. Some of these naturally find their way Into the field and under favorable conditions become destructive. Cabbage yellows may also be distributed with the seed but Is probably more commonly spread with the plants by the soil adhering to the roots.