18 
BULLETIN 128D, U. S. DEPARTMENT OF AGRICULTURE 
DEPTH OF SEEDING 
In order to determine the effect of seeding at different depths, 
experiments covering a period of three years were conducted at Cor- 
vallis, Oreg. The data are given in Table 10. From this it is apparent 
that depth of seeding has nothing to do with yield; at least this is 
the case when the seeding depths are within the range of usual farm 
practice. The essential factor in depth of seeding is to obtain 
moisture conditions favorable to the germination of the seed. 
Table 10. — Yields per acre of seed and hay of Oregon retch when seeded at various 
depths 
[Computed from duplicate twentieth-acre plats] 
Product and depth of seeding 
Seed: 
1 inch 
2inches 
3inches 
4inches 
Hay (dry-matter basis): 
1 inch 
2inches 
3inches 
4inches 
Date of seeding 
Oct. 14, Nov. 3, | Nov. 10, 
1915 1916 1917 
Pounds 
1,590 
1,690 
1.610 
1,640 
5,300 
6,500 
6,440 
6, 4b0 
Pounds 
2.065 
2.046 
2.040 
2,090 
6.400 
6,500 
6,660 
Pounds 
1,025 
1,120 
1.200 
1,050 
5,560 
5.0G0 
5, 340 
5,580 
Total 
Average 
Pounds 
Pounds 
4,680 
1,560 
4,856 
1.619 
4.850 
1.617 
4,780 
1,593 
17,260 
5, 753 
18. oeo 
6.020 
18, 440 
6, 147 
is, ceo 
6.220 
CONTINUOUS CROPPING AND ROTATION WITH OATS COMPARED 
The data from experiments conducted at Corvallis, Oreg., com- 
paring continuous cropping to Oregon vetch with rotations of Oregon 
vetch and oats are given in Table 11. On account of weather con- 
ditions the vetch-seed crop was a failure in 1918 and all the plats 
were harvested for hay. The difference between the yields of vetch 
seed on the continuously cropped plats and on the rotation plats 
was greater in 1916 than in 1920 or 1922. the heaviest yields being 
always on the rotation plat. However, the difference in the ratio 
of the vields was very slight. The ratio in 1916 was 1 : 1.098 and in 
1920 and 1922 it was 1:1.100 and 1:1.166, respectively. These 
differences are very small and indicate that there has been no 
decrease in vetch-seed yield due to the continuous cropping. How- 
ever, it is clearly indicated that there has been an increase in yield 
due to the rotation. 
Table 11. — Yields per acre of Oregon retch under continuous cropping and in 
rotation with oats 
[Computed from duplicate twentieth-acre plats; hay yields computed on a dry-matter basis. The asterisk 
(*) marks a year of crop failure] 
Year harvested 
Planting 
date 
Stand 
Vetch continuously 
planted 
Vetch rotated with oats 
Seed 
Straw 
Bay 
Crop 
Seed 
Straw 
Hay 
1915 
Oct. 15 
Nov. 4 
Nov. 10 
Oct. 3 
Oct. 29 
Oct. 6 
Oct. 2s 
Oct. 21 
Oct. it 
Pit cent 
100 
"loo" 
100 
100 
100 
100 
100 
100 
Pounds 
1,520 
2,285 
1 . 925 
(*) 
1.9S0 
1.200 
1,000 
oeo 
1,040 
Pounds 
"5.2t : 
7,"320 
4,920 
4,300 
Pounds 
6,140 
7,980 
6,720 
2, 520 
8,520 
6,980 
7. K'(l 
t. 100 
4.000 
Oats 
Vetch . 
Oats 
Vetch... 
Oats 
Vetch- 
Oats 
Vetch... 
Oats 
Pounds 
2.270 
2.510 
2. n^s 
<*) 
2. 530 
1.320 
2.7-50 
1,120 
2. 400 
Pounds 
Pounds 
1916 
2.1(6" 
7, _ 6C6" 
I. "Ml 
5.300 
8.220 
1917. 
1918... 
2, I'd 
1919 
1920-. 
6,780 
1921 
1922... 
4,280 
1923 
