60 BULLETIN 1301, U. S. DEPARTMENT OF AGRICULTURE 
no more readily obtained than :s a stand of alfalfa, which remains 
productive for a longer time. 
Sweet clover, it seems, should be a secondary crop in a region where 
alfalfa can be grown successfully. It has not been equal to alfalfa in 
vield or quality of hay in any year at the station at Mandan. During 
the pene 1915-1919, inclusive, alfalfa was seeded once for eight 
crops (two cuttings each season), and sweet clover was seeded four 
times for four crops. 
The yields for 1914 shown in Table 21 were from plantings made 
that spring. No yields were recorded for 1915, as the 1914 seeding 
winterkilled and was plowed up in the spring. Where no yields of 
sweetclover are recorded in Table 21, it is because a stand was not 
obtaimed during the previous season or because of winterkilling. 
ALFALFA AND GRASS MIXTURES 
In Table 21 yieids of an alfalfa and brome-grass mixture are shown. 
The hay was of excellent quality. The yields were lower than those 
from alfalfa alone, because brome grass gradually crowds out the 
alfalfa. 
A mixture of alfalfa, brome grass, and crested wheat grass was 
seeded in a field along a coulee in 1919, and the alfalfa did not winter- 
kill in 1919-20. The rate of seeding was approximately 4 pounds of 
alfalfa, 6 pounds of brome grass, and 6 pounds of crested wheat grass, 
to the acre. The yields were about the same as those from the alfalfa 
and brome-grass mixture. 
PERENNIAL GRASSES 
Table 22 presents the yields produced by smooth brome grass 
(Bromus mermis), crested wheatgrass (Agropyron cristatum), slender 
wheat grass a tenerum), and western wheat grass (A. smitha). The 
main point of interest is the yield of crested wheat grass, which has 
been higher than that of any of the others. Crested wheat OTass 1S 
a bunch erass brought into this country from Siberia some years ago 
by the United States Department of Agriculture. It has been grown 
at a number of field stations, and during recent years its value as a 
hay crop has compared favorably with brome grass and other wheat 
grasses. Crested wheat grass produces seed of high quality. It 
can be sown with a drill the same as wheat. It has been sown at the 
station in rows 42 inches apart. It has also been sown in drills 6 
inches apart, 10 to 15 pounds per acre, but no yield records are avail- 
able from the drilled plats. 
Table 22 shows that the average yield of crested wheat grass was 
higher than that of brome grass or the other wheat grasses. Tt makes 
hay of high quality that is readily eaten by stock. Crested wheat erass 
at Mandan starts growth early in the spring, usually a few days before 
brome grass, but after it has matured one crop it does not grow any 
more until fall, when it usually makes some growth which would be 
of value for pasture. 
Brome grass is the cultivated grass most commonly grown. It 
produces fair crops of hay‘ when first sown, but soon becomes sod- 
bound and low yielding. It has been sown at the rate of 10 to 15 
pounds to the acre, usually by hand or by mixing it with grain. It 
does not seed readily with a grain drill, but an agitator attachment 
that makes the grain drill handle brome €-8Tass Sec ‘dina satisfactory 
manner has been made and used at the station. 
