Density of stand in seedbeds influences seedling size. As size of
seedling is important in budding and grafting black walnut, information
on the most desirable spacing in seedbeds was needed. In three seedbeds
Thomas nuts were planted in three nut spacings: 4 x 4 inches, 5 x 5
inches, and 6 x 7 inches. In other plots nuts were planted 4 x 4 inches
and after emergence the stand was thinned. All seedlings from the
thinning test were set out in nursery rows the following spring and
those large enough were budded in the summer.
~Results~: Increasing the spacing produced seedlings of larger girth and
shorter height--a desirable characteristic in black walnut budding
stocks. The most desirable spacing appeared to be 6 x 7 inches. Even
though the number of seedlings resulting from this spacing was
approximately half the number produced at 4 x 4 inches spacing, more
usable seedlings were produced at the wider spacing.
Thinning seedlings spaced 4 x 4 inches resulted in larger girth of those
remaining--very similar in size to seedlings spaced 5 x 5 inches.
Seedlings from the thinned and unthinned plots averaged 0.62 cm. and
0.55 cm. in diameter, respectively. In the nursery row 73 percent of the
larger transplanted seedlings were large enough for budding the
following summer, while only 59 percent of the smaller seedlings
attained proper size. Bud survival was 22 percent on the larger stocks
indicating the desirability of using large stocks.