74 
Research Bulletin No. 3 
the most vigorous growth of all (see the upper row in figure 16) 
but they had completely exhausted the free water before any 
plants had put forth heads. These two were the only milo plants 
which formed any tillers. Each formed one, that in the case of 
IV being removed on March 26 and that in the case of III on 
April 16, both being less than 6 inches long. At the end of April 
both plants were already suffering seriously from drouth and 
neither showed any sign of putting forth a head. Both were in 
worse condition on May 13. There was little difference between 
the two plants at this time but that in III seemed to be in the 
better condition ; the plant in this was harvested and the cylinder 
opened. That in IV was left a month longer. It was almost en- 
tirely dead on June 11 and was harvested three days later, being 
then quite dry. 
The roots in both were abundant and uniformly distributed. 
The surface soil of IV contained 2.0 per cent less water than that 
of III but there was little difference in the amount of moisture 
in the subsoil — it being practically exhausted in both. If, as is 
probable, the subsoil moisture was at least as low in IV as in III 
on May 13, it is of interest that it was no lower at the end of an- 
other month, one of very high temperature. 
The loss of moisture from the surface foot of soil of IV which 
occurred during the last month, assuming that it was as dry as 
in III on May 13, is to be attributed almost entirely to direct 
evaporation, as the free moisture had already been entirely re- 
moved. 
MEXICAN BEANS. 
Mexican pink beans, from the Sulphur Spring Valley Dry- 
Farm of the Arizona Experiment Station, were planted on Febru- 
ary 5 in cylinders I and II, filled as described on page 48, the sur- 
face foot of soil containing 25 per cent and the subsoil 18 per 
cent total water. On February 22 the plants were thinned to 
the most vigorous two in each cylinder. On March 29 all the 
plants were in bloom, the two in I being 7 and 9 and those in II 
being 9 and 13 inches high. Many pods formed on each of the 
plants but most of these failed to fill. By April 23 leaves were 
beginning to drop from all four; the photograph (figure 18) was 
taken on that day. On April 27 the two plants in I wilted badly 
and did not recover, both being dead on April 30. A week later 
all the leaves seemed quite dry, but the pods and stems not being 
dry the cylinder was left until May 13. The plants in II held out 
for over a week longer, wilting for the first time on May 7. They 
were dead two days later and quite dry by May 13. 
On the death of the plants, as will be seen from Table 18 and 
figure 7, there was a very uniform distribution of moisture 
