29, BULLETIN 1031, U. S. DEPARTMENT OF AGRICULTURE. 
Areas of loose sandy soil dried out more quickly and were subject to 
greater injury than areas of the more compact finer textured soils. 
The difference was increased by the action of wind as well as differ- 
ence in soil and moisture. Local areas of loose sandy soil were re- 
duced to wind-blown wastes. 
Because of the small amount of inferior grasses and long-lived 
perennial weeds on the two areas under study a conclusion as to 
the behavior of such vegetation is not warranted. This class of 
forage is not of great value except during wet springs, when it 
furnishes considerable early feed. 
Vegetation of the character that usually lasts but a single year is 
not so materially affected by drought, because the plants depend 
upon the surface soil for their moisture, which might be supplied 
by showers at the proper season of the year, even during drought. 
The largest number of such plants occurred during 1917 and 1918, 
the driest years of the drought. This might easily occur, since the 
high winds increased dissemination and planting of the seeds, the 
rain that fell was sufficient to moisten the surface soil to promote 
growth, and competition by the main grasses had diminished. The 
volume of forage furnished by this kind of vegetation on range 
used in winter is negligible, however, since the plants dry up and 
blow away soon after the growing season. 
Aside from the reduction in density of the forage stand due to 
drought, there was also a reduction in the height and foliage growth 
which further reduced the volume of forage. In 1917 the average 
height growth of ungrazed grama-grass was 13 inches, in 1918 it was 
only 8.6 inches, while in 1919, a year of more moisture, the average 
height growth reached 16 inches. It was difficult to measure in 
actual terms of quantity the difference in volume of forage produced 
due to variation in height and foliage growth on the ungrazed plots, 
because the previous year’s foliage was not removed and the dryness 
of the plants made it difficult to determine the amount that was 
actually dead. Careful estimates, however, placed this reduction in 
1917 and 1918 in volume of forage produced per unit area of vege- 
tative stand at not less than 20 per cent of the amount produced 
under average condition. More nearly average height growth and 
foliage production was reached in 1919 by the plants that survived 
the drought. 
From the grama-grass range under protection against grazing the 
data and estimates indicate a reduction in the stand of the most 
important forage plants of 8 per cent in 1917, 12.4 per cent in 1918, 
and 40.5 per cent in 1919, as compared with the stand in 1916. One 
of the plots observed had been under protection since 1913, the other 
since 1915, so that the stand in 1916 was probably near the maximum 
for the two sites which were chosen as representative of this type of 
