SOILS AND ALKALI. 
21 
of neutral alkaline salts. In most cases lime or gypsum, 
with deep tillage , will be of great benefit to the land. The 
presence of a carbonate of potash or soda can be known to 
the farmer by the alkali effervescing with strong vinegar, 
or by the fact that it dissolves the vegetable humus of the 
soil, and this dissolved humus is more or less black in 
color, and is what is commonly called “ black alkali .” 
One of the most important considerations in the alkali 
question is the water used, to irrigate the land. If this water 
is pure, as it is about Fort Collins, where the water comes 
from the melting of the snow upon the mountains, but 
little danger need be anticipated ; but if, on the other hand, 
the water used, as in some parts of California, is itself a 
xlilute solution of alkali, and in some cases not very dilute, 
the farmer is but adding fuel to the flame. 
The kind of crop that will shade the soil and prevent 
evaporation from the surface will be best adapted to alkali 
soils. It may be said that an accumulation of alkali around 
the roots of the crops would be injurious, but it must be re¬ 
membered that the solution is very dilute and could not 
injure the crop. When the ground is hoed during a dry 
time, the capillary pores are cut off at the surface and 
evaporation is prevented, or at least very much lessened; 
therefore, a hoed crop would be valuable on alkali soil. 
Owing to the expense, the question of sub-irrigation has 
not been tried in a practical way where I have had an op¬ 
portunity to examine it. There are two arguments in 
favor of sub-irrigation, viz: It would prevent the rise of 
the alkali and accomplish a saving of all the water lost by 
evaporation. If the farmer wants to reclaim his valuable 
bottom land, he must provide a system of drainage by 
which the surplus subsoil water is carried off to the rivers 
and other places, or he will share the fate of the people of 
India and their “ reh ” (alkali) lands. It is to be hoped, some 
day in the near future, that the Government will build res- 
