CEREAL EXPERIMENTS AT JUDITH BASIN SUBSTATION. 11 
age of land, all crops except winter wheat were grown on twentieth- 
acre plats. The tenth-acre plats are 2 rods wide and 8 rods long, 
with alleys 3^ feet wide between the plats and roads 1 rod wide be- 
tween the blocks or series of plats. The twentieth-acre plats were 
1 rod wide and 8 rods long, with 20-inch alleys. 
In 1913 some of the winter wheat varieties were grown on acre 
plats. These plats were 8 rods wide and 20 rods long. The spring- 
wheat varieties were grown in fiftieth-acre plats, and the rest of the 
spring cereals in tenth-acre plats. In 1914 and 1915, part of the 
winter-wheat varieties were grown in acre plats and the spring 
cereals in fiftieth-acre plats. The fiftieth-acre plats are 6 feet wide 
and 8 rods long, with 18-inch alleys. This plat is actually one fifty- 
fifth of an acre in area, but as some moisture and plant food are 
drawn from the alleys, it seems fair to consider them as fiftieth-acre 
plats in computing acre yields. 
Fig. 4. — General view of the cereal experiment plats at the Judith Basin substation, Moccasin, Mont., 
1910. 
REPLICATION OF PLATS. 
From 1908 until 1913 all varieties were grown in single tenth-acre 
or twentieth-acre plats. In every year except 1908 check plats of a 
standard variety were grown. In 1913 the spring- wheat varieties 
were grown in replicated fiftieth-acre plats, and in 1914 and 1915 all 
crops except the winter-wheat varieties in acre plats were grown in 
this way. A 6-foot drill is used and one drill width across the series 
(8 rods) covers one-fiftieth of an acre. As stated before, these plats 
are really one fifty-fifth of an acre in area, but in computing acre yields 
they are considered as one-fiftieth of an acre. In the system of plat 
replication in use at the Judith Basin substation five plats of each 
variety are grown. These plats are distributed throughout the space 
devoted to the test. In computing the yields of the varieties grown 
in replicated plats the average yield of the five fiftieth-acre plats of 
any one variety is obtained and the acre yield then computed. 
PREPARATION OP THE LAND. 
With few exceptions all the varietal tests of cereals have been con- 
ducted on fallow ground. In 1908 the crops were sown on sod 
