EXPERIMENTS WITH FLAX ON BREAKING. 11 
mitted backsetting the same fall. Each year the flax was grown on 
land which had been broken and backset the previous summer, and 
double-disked and harrowed in the spring before seeding. A disk 
drill was used in seeding the plats. Alleys and roads were cultivated 
at intervals during the season, and hand weeding the plats was neces- 
sary in order to maintain uniform conditions for all plats and to keep 
the station free from undesirable weeds. Yields from experimental 
areas probably should be discounted somewhat, to offset the favorable 
conditions arising from the effect of the alleys upon the plats and the 
hand pulling of weeds, which doubtless would have lowered yields. 
INTERPRETATION OF EXPERIMENTAL RESULTS. 
Yield of seed is the predominating factor in the value of a variety 
or cultural method when flax is grown for the seed alone. Other fac- 
tors are worthy of serious consideration, however. Some of these are 
earliness of maturity, a definite period of bloom, height, erectness of 
straw, and yield and quality of oil. Distinctive characters of flower 
or seed are desirable, but in the experiments reported no factors of 
this kind enter into consideration. 
The continued growing of certain types and varieties in the nursery 
can be justified only on the basis of classification studies and. their 
utilization in hybridization. Some possess characters or character- 
istics of growth which, if combined properly with other types, may 
give strains of superior value. At Mandan, too, the breeding ex- 
periments for the entire flax project are concentrated, and strains 
are continued here even when they do not appear promising, if they 
are known to be of value in other areas. 
The yields obtained in these three years undoubtedly are high, as 
the rainfall during this period was excessive when compared with the 
normal for this section. It is doubtful, also, whether the results dur- 
ing three years supply an adequate expression of what may be ex- 
pected from rates and dates of seeding, as these results vary greatly 
from year to year, depending upon the weather. The relative yields 
of the different varieties conform more or less closely, however, to 
those obtained in similar experiments at other stations. 
FLAX EXPERIMENTS IN PLATS. 
Plat experiments were confined to the study of varieties and of 
rates and dates of seeding. Complete experimental data were ob- 
tained on 14 varieties grown for the three years in replicated plats. 
HISTORY AND DESCRIPTION OF VARIETIES. 
The 14 strains and varieties in this experiment were selected from 
the most promising ones being grown at State and Federal stations 
in the Northwest in 1913. These had been or were assigned Cereal 
Investigations accession numbers and, for the sake of brevity, will be 
referred to by these numbers. 
