a8 BULLETIN 1301, U. S. DEPARTMENT OF AGRICULTURE 
merly physiologist in that office, was in charge of the field experi- 
ments, and was stationed at Mandan in 1919 and 1920. During 1921 
the trials were continued by the Office of Dry-Land Agriculture 
Investigations without cooperation. In 1922 the work was in coop- 
eration with the Office of Forage-Crop Investigations under the field 
supervision of H. L. Westover.*® 
ALFALFA AND SWEET CLOVER 
Alfalfa probably is the most valuable hay crop that can be grown 
in this area, because it yields well and makes hay of high feeding 
value. The severe winters which sometimes occur necessitate the 
use of hardy varieties. A combination of severe conditions occa- 
sionally kills even these, but this does not occur often enough to 
destroy the value of alfalfa as a hay crop for this area. During the 
winter of 1919-20, all varieties of alfalfa at the station completely 
winterkilled except the yellow-flowered variety (Medicago falcata), 
which was 30 per cent killed. This extensive winterkilling was prob- 
ably because of the dry summer and fall of 1919 and the unusual 
weather conditions early in the winter. Alfalfa that was located 
along a coulee and protected by snow did not winterkill. 
Table 21 gives the yields of alfalfa, sweet clover, and a mixture of 
alfalfa and bromegrass for the years these were grown (1914 to 1922, 
inclusive). In 1915 alfalfa was seeded on native sod broken the 
previous summer, and a light crop was harvested. During each of 
the other years until it winterkilled in 1919-20, two crops were 
harvested. The alfalfa was seeded in drills 6 inches apart and in 
rows 42 inches apart. The average difference in yield was slight. 
The hay from the rows was coarser and contained considerable dirt. 
The rows also required cultivation two or three times during the sea- 
son. The hay from the drilled plat was free from dirt, and the only 
labor in connection with it was harvesting. 
TABLE 21.—Yields of field-cured alfalfa, sweet clover, and mixed alfalfa and brome 
grass hay at the Northern Great Plains Field Station, 1914-1922, inclusive 
{ Where no yields are recorded it is because a stand was not obtained during the previous season or because 
of winterkilling] 
Yields per acre (pounds) 
ay, caveat yo Seeding 
Crop and variety Ter - 
1914 1915 1916 | 1917 | 1918 | 1919 | 1920 | 1921 : 1922 
Alfalfa: 
Grimms 5 22 eee eae Drilled (aes 8,350! 3,900) 4,610} 3, 640}__-- -_|------|_--=_- 
DOS OB RY ee ows. _. | ae 6, 350) 4, 750) 5,290) 3; 880)" = | ee eee 
Sweet clover: 3 
Wiiite= ss! Saar se ee! Drilled__-_] 2 200)_--._- 504.50] ee A) ee ESS Lee Uae Ses 22e 
DQ Seer See ee OE Rows... |-2500 2 1.600) 1,300) 222 a 2 470) 4-215) = 
Wellow2 eit 2 tee: wee ee ae Drilled see ee ee 227301" oe 15730} 
WG! cee oh, Sa ee eee Rows... meee ee ea eee 3; 390)) 22 4 AND 2 
Alfalfa and brome grass mixture __| Drilled____|______ 2,800) 6,950; 2,350) 2, 700) 3, 520)-_---_}------ paar 
Alfalfa in the ordinary tests was sown without a nurse crop at the 
rate of 5 to 8 pounds per acre in drills 6 inches apart. When sown 
in rows 42 inches apart, the rate of seeding was approximately 1 pound 
per acre. The seeding was done with a grain drill having a grass- 
seeder attachment. With seed of high quality and a favorable season 
10 This report of the experiments with forage crops was prepared by J. T. Sarvis and approved by A. C. 
Dillman and H. L. Westover. 
