r to thoroughly test the possibilities of direct seeding as an
economical method of establishment, this Division during seven years
(1939 to 1942, and 1944 to 1946) planted over 7,000 nuts by direct
seeding in 200 locations in 18 eastern States. It was suspected that the
greatest hazard to direct seeding in or near forests would be rodents.
Accordingly, in the spring of 1939 and 1940, 400 nuts and 600 nuts,
respectively, were coated with a strychnine-alkaloid rodent repellent,
and a comparable number of seeds, for both years, were left untreated to
serve as checks. The checks were held in sphagnum moss at Beltsville,
Md., and the nuts to be treated were packed in sphagnum moss and
expressed to Denver for treatment by the Division of Wildlife Research,
the Fish and Wildlife Service, Department of the Interior. Only 5.9 and
2.5 per cent of the treated seeds developed into seedlings, whereas 22.6
and 13.5 per cent of the untreated seeds produced seedlings. Not only
did more of the treated seeds fail to germinate than of the untreated
seeds, but the seedlings from the treated nuts were less vigorous.
Because of the results obtained, the rodent-repellent study was
discontinued at the end of the second year.
In 1941 and 1942, over 4,000 untreated chestnut seeds, representing 22
strains, were planted in 12 locations in eight eastern States. The seed
source was entirely from American-grown, Asiatic chestnut trees growing
in 28 locations in 16 eastern States. They represented Chinese,
Japanese, hybrids, and also a limited quantity of American chestnut
seed. Seed of the American species was included primarily to determine
whether or not it differs from the Asiatic species with reference to
establishment by direct seeding. The results for the two years confirmed
our earlier beliefs: Only 2.2 per cent in 1941, and 4.0 per cent in
1942, developed into seedlings, of which only a remnant have survived.
No species or strain differences were apparent.
"Tin Can" Method
In 1944, the tin-can method was employed in planting 400 nuts in four
eastern States. By this method 15.5 per cent of the planted nuts
developed into seedlings, representing a fourfold increase over results
obtained for the three previous years. One end of a No. 2 can is
removed, and a cross is cut in the other end with a heavy-bladed knife.
The open end of the can is then forced into the ground, over the planted
nut, so that the top lies flush with the ground level
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