THE DETERIORATION OF MANURES UNDER SEMI-ARID 
CONDITIONS. 
By W. P. Headden and Earl Douglass. 
INTRODUCTION. 
For many years prior to the introduction of the sugar beet as a 
commercial crop it was the practice of most Colorado farmers to throw 
away the manure made upon the farm. The land seemed to be in¬ 
exhaustibly fertile and work spent in spreading manure upon the 
land was considered labor wasted. In the early years of our agri¬ 
cultural development, this was, to a certain degree, true. The soil 
gave bountiful crops year after year, and any additional fertility 
seemed to do more harm than good by increasing stems and leaves at 
the expense of grain. During these years the manure, much of it 
first-class sheep manure from sheep which had been fed upon corn 
and alfalfa, was dumped into the creek beds or sloughs, or left upon 
the ground, and the corrals were moved when the layer of manure 
became so thick that the sheep were likely to jump the fence. 
Manure of More Importance than Formerly. 
The growing of sugar beets and more intensive methods of farming 
have changed this, and in those districts in which there are sugar fac¬ 
tories, the manure is' now carefully saved and spread upon the land. 
More thought is given to saving the manure and to increasing the 
supply by fattening cattle or sheep on the farms, the value of the 
manure being now taken into account as part of the profits. There 
are still too many places in Colorado where the soil is being robbed, 
while the means of restoring, or at least partially restoring the fer¬ 
tility is going to waste in neglected manure heaps. 
The question of the deterioration of manures under our Colorado 
conditions is important for the reason that the high freight rates 
make it impracticable for the western farmer to use the commercial fer¬ 
tilizers which are in common use in sections nearer the great dis¬ 
tributing centers, the sea ports and packing houses. In the west, 
very little attention has been paid either to the subject of fertilizers 
or barnyard manures and, so far as we know, no analytical data are 
at hand on the deterioration of manures under semi-arid conditions. 
Fresh Manure Should Not he Used on Irrigated Soils. 
Another question arises, when discussing the deterioration of 
manure, namely, the effect of fresh manure upon soils which are 
sometimes watered scarcely enough to produce a crop. In order to 
prevent waste of the elements of fertility under humid conditions, the 
general practice has been to use the manure as fresh as possible. 
It probably seems improvident on the part of our fanners to 
