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phoric acid, and potash, attributing neither influence nor 
value to the other fertilizing elements, which is justifiable 
only on the ground that we have neither a commercial 
nor a conventional measure of value for them, particularly 
the easily decomposable organic matter which has more 
value in our soils than it would have in many others. I he 
humus in our soils is not high—in the samples given 0.4 
and 0.2 per cent, respectively—and they produce good crops, 
but the addition of this form of organic matter 
would better their mechanical condition and very probably 
their productiveness. As the increase of humus in these 
prairie soils is not easy, I believe that we ought to value 
highly the easily decaying alfalfa roots. 
There is still another manner in which the growing 
of this plant benefits our lands for cultivation : it opens 
up channels through compact substrata to a considerable 
depth, allowing the entrance of water and air. The writer 
unfortunately does not know whether hardpan streaks are 
frequently met with or not, but, so far as his observation 
goes, they are not; compact layers are met with, but the 
alfalfa roots have penetrated all of these which he has ex¬ 
amined with this point in view. The size and length of 
the average roots in this country are not at all consonant 
with popular estimate, nor yet with the descriptions given 
of them as found elsewhere ; but their power to penetrate 
tough clays and hard streaks is great enough to make them \ 
most excellent subsoilers. The soil of a field which has 
been to alfalfa has practically been deepened for a subse¬ 
quent sowing to wheat. I have not seen, nor do I know of 
any observations having been made upon the root develop¬ 
ment of wheat in our prairie soils or as to the depth to which 
they penetrate in virgin soil, where there is a very fine, com- 
pact, and tough substratum, the result of the settling and 
compacting of ages To plant such a soil to alfalfa is to perfor- 1 
ate this compact subsoil with numerous channels for the pas¬ 
sage of water and air and for the entrance of other roots 
when those of the alfalfa have rotted. The work done by I 
the alfalfa roots in accomplishing this is very great, but this 
work is to the benefit of the soil,the advantage of the sue- 1 
ceeding crops, and to the profit of the owner, being the 
cheapest labor as well as the best directed and most effi¬ 
cient of any which he can employ. 
A very common practice among our ranchmen ought 
to be particularly mentioned here, though it is only inciden¬ 
tal to the object of this bulletin and is self-evident, needing 
only that attention should be directed to it. I he great 
benefit accruing to worn out wheat soils by being sown to 
