EXPERIMENTS WITH FALLOW IN MONTANA 
which alternates with fallow and those obtained on fallow in rota- 
tions where fallow appears less frequently. The yields given for 
continuous cropping are the averages for all plats continuously 
cropped to any grain, regardless of the methods used in preparing 
the seed bed. For example, the average for continuously cropped 
spring wheat is the average of all plats on which spring wheat was 
grown every year, although these plats had different cultural treat- 
ments in that some were fall plowed and some were spring plowed. 
There was also a difference in the depth of plowing, but the depth 
has made no consistent difference in the yield where the crop was 
grown continuously. 
Table 3 gives the annual and average yields of spring wheat, oats, 
and barley on fallow, on disked corn ground, and with continuous 
cropping for the seven years from 1917 to 1923, inclusive. For 
these years spring wheat averaged 12.4 busHels on fallow, 9.2 bushels 
on disked corn ground, and 5.7 bushels with continuous cropping; 
oats averaged 23 bushels on fallow, 16.7 bushels on disked corn 
ground, and 12.6 bushels with continuous cropping; and barley 
averaged 16.1 bushels on fallow, 10.7 bushels on disked corn ground, 
and 6.8 bushels with continuous cropping. The different tillage 
methods had the same relative values for the three crops, the yields 
on fallow being highest, those on corn ground second, and those 
under continuous cropping the lowest. In 1919, a year of generally 
poor yields, the yield on corn ground was higher than on fallow. 
With this exception the relation between the three methods was 
quite consistent from year to year. For spring wheat, cornland 
compared most favorably with fallow in 1918, 1919, and 1920 and 
least favorably in 1922, when the yields from cornland were rela- 
tively low, being even low T er than those on continuous cropping. 
The highest yields of oats were on fallow in all years except 1919, 
when all yields were very light and the yields on cornland were rela- 
tively high. The highest yields of barley were on fallow with the 
one exception of 1919. 
The yields of wheat, oats, and barley with the three distinct prep- 
arations, as presented in Table 3, are shown graphically in Figures 1, 
2, and 3. 
Table 3. — Yields of spring wheat, oats, and barley on fallow, disked corn ground, 
and with continuous cropping, 1917 to 1928, inclusive 
Previous crop, if any, and 
tillage method 
Num- 
ber 
of 
plats 
Yields per acre (bushels) 
Crop 
1917 
1918 
1919 
1920 
1921 
1922 
1923 
Aver- 
age 
[Fallow 
4 
9 
4 
18 
8 
16 
4 
4 
10 
11.0 
7.3 
4.1 
23.5 
10.3 
8t2 
18.9 
10.0 
7.8 
8.4 
8.4 
4.9 
11.1 
8.1 
8.9 
9.5 
8.8 
5.1 
4.3 
5.1 
1.3 
3.1 
8.1 
.9 
2.4 
5.2 
1.5 
12.8 
11.3 
6.4 
25.4 
21.9 
21.1 
16.9 
13.9 
11.1 
15.5 
11.4 
7.7 
38.4 
24.0 
19.4 
26.4 
9.8 
8.7 
12.2 
2.7 
2.9 
23.8 
14.2 
7.6 
18.0 
9.5 
3.7 
22.9 
18.5 
12.8 
36.2 
30.3 
22.3 
20.3 
17.7 
9.8 
12.4 
Spring wheat . . 
■(Corn, disked 
9.2 
[Wheat, continuous crop 
[Fallow 
5.7 
23.0 
Oats 
<Corn,disked... . 
16.7 
lOats, continuous crop 
[Fallow 
12.6 
16.1 
Barley 
<Corn, disked . 
10.7 
(Barley, continuous crop 
6.8 
1 Nine plats in 1919 and after. 
