10 BULLETIN 398, U. S. DEPARTMENT OF ACrPJCLLTLEE. 
date-of-seeding, and rate-of-seeding tests of winter and spring wheat, 
and spring oats, barley, and flax. In different years the number of 
varieties under trial has varied from 75 to 125. The number of plats 
in the date-of-seeding and rate-of-seeding tests has ranged from 40 
to 60. so that the total number of experiments has varied from 115 
to 185. 
The nursery work at Moccasin covers two general lines: (1^ The 
introduction and testing of new varieties, and (2) experiments in the 
improvement of cereals. Xew varieties are usuaUy tested in nursery 
rows before being grown in plats. This makes possible the testing 
of a large number of varieties with much less time and labor than 
would be necessary hi larger plats. 
The effort in the improvement work has been to select individual 
heads representing desirable types. These selections usually are 
made from the varieties that have given the best results in the plat 
Fig. 3.— Buildings at the Judith Basin substation. Moccasin. Mont., in 1915. (From a photograph 
lent by the Office of Exhibits, U. S. Department of Agriculture.) 
tests. These selections are multiplied and tested for yield and other 
desirable characters, such as length and stiffness of straw and freedom 
from shattering. The poor selections are discarded and the prom- 
ising ones increased. 
The number of rows has varied from 256 in 1909 to S40 hi 1911. 
Most of these are devoted to the improvement work. Since 1911 the 
number of rows has been reduced as the poor selections are dis- 
carded and the promising ones increased. 
EXPERIMENTAL METHODS. 
That portion of the substation farm used for plat work is divided 
into blocks 132 feet wide and 617 feet long, which are separated by 
roads 1 rod wide. These blocks may be divided into tenth-acre, 
twentieth-acre, or fiftieth-acre plats, each 132 feet, or S rods, long. 
Plat Experiments, 
size of plats. 
All of the varieties in 1908 and 1909 and nearly all in 1010 were 
grown on tenth-acre plats. In 1911 and 1912, because of the short- 
