There are a large number of forms of kale, and these are thought by
some to be the original type of the cabbage. Kale does not form a head
and has convoluted leaves and thick leaf stems. It is cultivated the
same as cabbage, but may be set somewhat closer. This crop is very
hardy and will live through the winter in the open ground in localities
where freezing it not too severe. The flavor of kale is improved by
frost. Kale is used for greens during the winter, and as a substitute
for cabbage.--(F. B. 255; N. Car. E. S. 132; U. Id. E. S. 10.)