planted European chestnut orchards of the Pacific Coast from time to
time, but it has been kept under control by eradication. Chestnut trees
or nuts from the eastern States, where blight is common, should not be
shipped into the Rocky Mountain or Pacific Coast States.
Finding the Asiatic chestnuts resistant to the blight, the Division of
Forest Pathology sent R. Kent Beattie to Asia to make selections of
chestnuts for introduction into this country. Later Peter Liu, a Chinese
collector who worked with Mr. Beattie, continued to select Chinese
chestnuts for introduction. These introductions, together with the
earlier ones made by the Division of Plant Exploration and Introduction,
were grown at Chico, Calif., Savannah, Ga., and Bell, or Glenn Dale, Md.
Altogether some 300,000 chestnut trees, of pure species and hybrids,
were distributed to cooperators for forest and orchard plantings. (Fig.
1.) These constituted a fine lot of material from many parts of Asia as
a basis for selecting the best ones for our use. Private nurseries and
State game and forestry departments are now growing these chestnuts and
the Division of Forest Pathology has discontinued general distribution
of trees to cooperators.
Chinese chestnuts have proved to be the most valuable for forest,
orchard and ornamental use. The Japanese chestnut is being discriminated
against because of the poor quality of its nuts. Orchardists having
mixed plantings containing Japanese chestnuts are advised to top work
the trees or remove them, if the seed is to be used for plantings. In
fact, for orchard plantings, nuts should be used only from the best
individual trees of the Chinese chestnut.
The Chinese chestnut should be planted on sites with good air drainage
as it is very susceptible to injury from early-fall or late-spring
freezes. Many persons think their trees have been killed by the blight
when the primary cause of the trouble was injury to the trunk by
freezing followed by growth of the blight organism over the injured
parts. This fungus may grow for many years in the outer layers of the
bark without doing any material damage to the tree. An important factor
in resistance of the Chinese chestnuts to the blight is to keep the
trees growing vigorously. Avoid late growth in the fall as this favors
fall freezing damage.
[Illustration: Figure 1.--F1 hybrids between the Chinese chestnut and
the American chestnut.]
+Nut Spoilage+
In the Southern States
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