American Falls press. [volume] (American Falls, Idaho) 1907-1937, 1911-09-14
GRAIN SORGHUM CROP
Two Ways by Which 1t Can Be
Made of Greater Value.
MOST Useful In Regions Where Mois.
sure Is Often Controlling Factor
! n Crop Production Are
Drought Resistant,

CBy CARLETON r. BALL. Bureau nj
rant Industry. U. s. Department of Az
riculture.)
In general there are two ways BY
which the grain-sorghum crops can be
made OF greater value to the grower
Inc frst is by improving the varie.
ties; the second. by finding more rap
ID n economical methods of har.
Vestlng. Improved varieties can be
obtained through selection of present
sorts n by lettering the methods OF
growing them. More rapid and eco
nomical harvesting will come about
either through adapting the crops to
present machinery or through the in
Vention OF new machines, or both.
There are five principal ways in
which improvement may be made:
~ Increased drought resistance,
20 increased earliness, go dwarfer
stature. "a greater productiveness,
and 90 increased machine harvest
Ing.
The grain sorghums are most use.
full In regions where moisture is often
the controlling factor in crop pro-
duction. Much good should therefore
be accomplished by increasing their
drought resistance. especially In the
areas of lighter rainfall.
NO one knows exactly what drought
resistance Is. 1t is probable that
wnat we call drought resistance is
the effect of several different factors.
b most important of these factors
are probably 1) increased ability to
prevent the loss Of water by transpi-
ration, CD increased DEVELOPMENT of
the root system, and 60 a possible
Increase in power to extract water
from a dry soil.
D1rerences In the power to control
Transportation are well-known and
readily observed facts. By transpira-
ton is meant the passing OF water
from the tissues of the plant into the
air. In the processes of their growth
all plants are constantly absorbing
water from the soil through their
rootlets and allowing certain quaint
ties OF this moisture to pass out into
the air through minute pores, called
stomata. This Is done in much the
same manner as water escapes
through the animal skin in the form
OF p~erspiration. In times Of drought
1t Is important that the plant lose as
little as possible of it's water supply
In this way. The plant best fitted to
prevent Transportation is thus the most
drought resistant. In cacti, for in
stance, this ability is highly perfect
Cd. Corn is much less drought resist
am thar the members of the various
groups OF s%orghums. Corn is in dan
ger when the leaves begin to curl,
but %sorghums often remain in this
condition for a long time without per-
manent injury.
The size and character of the root |
system is probably a strong factor in
drought resistance. The larger the
root system in proportion to the plant
the better 1T can supply moisture. The
wider and deeper it's penetration, the
larger the area of soil from which 1t
draws moisture In times of drought.
A deeply roofing plant may be able
to secur water when shallow root
systems lie wholly in dry soil. This
Is entirely apart from possible diff
ferences in ability to secure moisture
from a given unit of soil. Such differ
ences may exist, but the idea is only
a theory as yet. Unfortunately, the
character Of the root system cannot
be observed while making observa-
tiOns