44 
Journal of Agricultural Research 
Vol. XXI, No. I 
Fig. 20.—Graph showing nitrogen content ol barley kernels from plots variously irrigated. Data shown 
are in milligrams per kernel and are averages of daily measurements dining each 3-day period. 
DISCUSSION OF RESULTS, 
The data presented show the course of development of kernels for 
different plots. Some facts, however, they do not and can not show. 
They show, for instance, that the development of kernels in plot 2 is not 
so great as in plots 3 and 4. t They do not show that a part of this is due 
to the extra culm formation on this plot as comparedWith those irrigated 
later. It is probable that the soil of plot 2 was somewhat below the 
average; but, in addition to this, there was a heavy development of 
culms which caused the water to be exhausted rather early in growth. 
The foliage of this plot showed that its plants were suffering from lack 
of water by July 30. On plots 3 to 8, the number of culms was much 
less, many of the secondary culms being arrested before they drew on the 
water supply. On the plots irrigated late in the series, wolf plants devel¬ 
oped which by their extra development used more than an average 
amount of water and caused some irregularities. These are apparent 
in the data from plot 5. The plot yields are not given, as the study was 
not planned to include so many factors as are involved in the total yield. 
The kernel weights bear no necessary relation to the yield per plot. 
The major point of the study is conclusive. Plants, even though 
suffering from drouth, are able to utilize water in late applications. 
On plots 6 and 7 the plants were well along toward maturity when water 
was applied. The advanced stage of maturity is not shown by the 
growth curves. The sterile lateral spikelets of plants in plot 8 had lost 
their green color by August 1—that is, plot 7 had been irrigated just 
before the actual abandonment of tissue in the spike took place through 
drying or maturity. By August 3 the color was disappearing on the 
side florets of plants in plot 2, which had begun to suffer from drouth a 
few days before. By August 4 the color was apparent only around the 
furrow of the kernels from this plant, and the lateral florets of plot 3 were 
