6 BULLETIN 222, U. S. DEPARTMENT OF AGRICULTURE. 
not have been the very best obtainable for that section, but by using 
the same variety in all of the methods under study uniformity in this 
factor has been obtained. 
Uniformity in rate, time, and manner of seeding has been observed 
on all plats at the same station. There is naturally some variation 
between the different stations. Differences in climatic conditions 
have been recognized in differences in the rate of seeding, but at the 
same stations it has been uniform. The usual rate of seeding has 
been 6 pecks of hulled barley and 3 pecks of hull-less. Both the 6-rowed 
and the 2-rowed barleys are hulled varieties. 
There is considerable variation in the time of seeding for the differ- 
ent field stations throughout the area, it being about a month earlier 
in the southern than in the northern portion. At some of the sta- 
tions the time of seeding is about the same as that of wheat and 
oats. At others it is a little later. All seeding has been done with 
a drill. Some stations, on account of the type of soil, have used the 
press drill in order to firm the soil around the seed. At other stations 
a drill without a press attachment has been used. 
For a comparative study of the effect of environment and for 
securing data on production, certain parts of the work are made 
uniform at all stations. This results in the attempted growth of bar- 
ley and other crops in sections to which they are not adapted and in 
their growth at certain stations by methods not adapted to the con- 
ditions obtaining there. 
Considering the fact that no two stations can have exactly the 
same combination of soil and climatic factors and that the combi- 
nation resulting from any two seasons is not the same, it is evident 
that the consequent effects of the different tillage methods will not be 
the same. Therefore, the results obtained from different methods 
at each station are given separately. 
In this bulletin a table divided into two parts is presented for each 
station. The first part shows the yields that have been obtained 
each year by each of the different methods under which barley has 
been grown, considering only the treatment during the one year imme- 
mediately preceding the crop. Where more than one plat has been 
grown under the same treatment for the previous year, only the aver- 
age yield of the whole number of plats so grown is given. Column 2 
shows the number of plats so averaged. In the presentation of 
yields, the column headed " Treatment and previous crop" indicates 
the method of preparation, whether fall plowed, spring plowed, listed, 
subsoiled, disked, green manured, or summer tilled. Some of these 
are again subdivided, to show the previous crop. In the last column, 
where the average appears under the heading ''Average," the calcu- 
lation is from the left. For a rough comparison of seasons, the bot- 
