8 BULLETIN 430, U. S. DEPARTMENT OF AGRICULTURE. 
The United States Weather Bureau, in reporting killing frosts, 
uses the staple crops of any given locality as a basis for determining 
the character of a given frost. Therefore, a temperature of 32° F. 
is not necessarily a killing frost, depending on the hardiness of the 
staple crops grown in the area under discussion. 
~ At Cheyenne the average frost-free period is 125 days. 
CHEYENNE EXPERIMENT FARM. 
LOCATION. 
The Cheyenne Experiment Farm is located in Laramie County, in 
southeastern Wyoming, about 8 miles east of Cheyenne and half a 
mile southeast of Archer. Archer is on the Union Pacific Railroad, 
while Cheyenne is on the Union Pacific, the Colorado & Southern, — 
and the Chicago, Burlington & Quincy Railroads. The farm is about 
Fic. 2.—Buildings on the Cheyenne Experiment Farm, Archer, Wyo., in 1915. (Photograph lent by 
the Office of Dry-Land Agriculture Investigations.) 
35 miles west of the Nebraska State line and 15 miles north of the 
Colorado State lime. It lies in about 41° 8’ N. latitude and 104° 48’ 
W. longitude. A view of the farm buildings is shown in figure 2, 
of the barns and silo in figure 3, and of a farmers’ round-up at the 
station in figure 4. 
DESCRIPTION. 
The farm consists of 250 acres. It was part of a large cattle ranch 
and for years had been used for grazing purposes. The soil is a sandy 
loam, varying in depth from 3 to 6 feet. Below these depths the soil 
is gravelly or sandy. The surface soil contais a low percentage of 
humus. 
The farm slopes gently a little south of east and excellent surface 
drainage is afforded. 
A map of the farm is shown in figure 5. The experimental work 
has been conducted on the west field. This field, of about 100 — 
