194 FACTS ABOUT CROP TREES
several nurseries, is merely a variety of the Japanese walnut. Some heart nut trees produce nuts whose kernel comes out in one piece—a fact of great commercial significance.
Consider the easy hybridization of the various species of walnut with each other. Consider this in connection with all the qualities above mentioned as well as the fact that Japanese and Manchurian and Chinese specimens come from sections of Asia having cold winters and hot humid summers.®
In view of these considerations it seems to be clear that we have the opportunity of making a great number of walnut hybrid varieties suited to a great number of climates and conditions. It may be easily within the possibilities that we can produce some kind of walnut to be grown especially for pig and poultry food.
5 "You will be interested to know that a letter from Dr. Edwin D. Weed. Duluth College. Duluth. Minnesota, states that Chinese walnut trees I sent him went through the winter 1925-26 well and are growing vigorously.
These were from ten thousand feet elevation in North China. (The seed)." (Letter. J. F. Jones, 1927.),
