Alkalis In Colorado 
29 
and often are, found in the same soil. They are independent of one 
another in their origin and are not always associated. 
We have given the views held in regard to the poisonous proper¬ 
ties of the important members of our alkalis and it has been fairly 
stated that the results of laboratory experiments made with solutions 
of these salts do not agree with the results found by observations made 
in the field, also that the explanation offered is that this difference is 
made by the presence of other salts in the soil solutions or in the soil 
which modify the action of these salts. It is an important fact that 
these alkalis are really much less harmful in the soil than we would ex¬ 
pect, judging from their action taken singly in laboratory experiments. 
While some investigators have spent much time and effort to as¬ 
certain the amount of these alkalis at different depths in the soil, it is 
agreed that only that alkali that gathers at or near the surface ever 
does any harm. As these alkalis get to the surface largely by being 
brought up from the lower portions of the soil, investigators have ex¬ 
amined the soils to a depth of 4 feet, which is a fair height for water 
to be lifted through the soil, and it is also a fair depth for the plant 
roots even of apple trees, for instance, to go down. 
TWO DISTINCT GROUPS OF ALKALIS 
It is necessary to separate the alkalis into two groups, one which 
does but little injury, and the other which does more, even great injury. 
To the less injurious group belong the calcic magnesic and sodic 
sulfates, and the chlorids of these elements. To the decidedly injuri¬ 
ous group belong sodic carbonate and the nitrates. Fortunately for 
us the less injurious alkalis constitute practically all of our ordinarilv 
visible alkalis. 
“WHITE ALKALIS” NOT INJURIOUS 
These alkalis, ‘‘white alkalis” as we designate them, which form 
so striking a feature of some sections of our State, especially in the 
spring-time after a light snow or rain, are very gentle indeed in their 
action. So gentle that I have not seen any bad effects which were 
clearly attributable to these salts. If, by chance, I have seen instances 
in which these salts really damaged plants I have failed to recognize 
them. I have seen, on the other hand, so many instances of their pres¬ 
ence, in such quantities that one would expect them to kill the plants, 
and they apparently did no harm, that I feel justified in making the 
general statement that in Colorado these alkalis constitute only an un¬ 
important factor in our agriculture. I recall a case in illustration of my 
last statement. There was a piece of land planted to corn. It was, of 
course, deeply creased and was watered profusely. The sides of the 
•creases just above the water had a band of white efflorescent salts, 
alkalis, between 2 and 3 inches wide, while the crowns between the 
