io • Colorado Experiment Station. 
because it can now be incorporated into the soil with advantage, and 
its humification may be completed in the soil while fresh manure 
may remain in the ground for years and produce objectionable re¬ 
sults. 
Loss in Two Years Found to be Less than Wolff Found in One Year. 
The second year a further loss of 35.9 percent of dry matter 
occurred, making a total loss of 56.7 percent of the original dry 
matter in about two years. There seem to be very few experiments 
which extend over a period of greater length than one year, and 
we have consequently none with which to compare this loss. Wolff 
found that an 8o-ton manure heap lost 65.5 percent of its dry matter 
in one year when exposed to wind and weather. This is much 
greater than our manure lost in two years. The total nitrogen 
decreased from 2.713 to 2.30 percent. 
Loss of Nitrogen, Potash and Phosphoric Acid. 
In order to compare the absolute losses to better advantage 
the results are calculated to pounds, and the losses given in per¬ 
cent. The original ten tons of manure contained 238.0 pounds of 
nitrogen, 341.3 pounds of potash and 102.8, pounds of phosphor¬ 
ic acid. 
In June, 1905, when the original 8,769 pounds of dry matter 
had shrunk to 5,920 pounds, there were 122.2 pounds of total nitro¬ 
gen, 355.1 pounds of potash and 59.44 pounds of phosphoric acid, 
or a loss of 48.64 percent of the nitrogen, and 42.17 percent of the 
phosphoric acid. The potash did not lose during the first year. 
In May, 1906, the manure had further decreased in weight to 
3,794 pounds of dry matter, and there were now present 76.27 
pounds of nitrogen, 228.1 pounds of potash, and 41.81 pounds of 
phosphoric acid. This represents a total loss in two years of 67.95 
percent of the nitrogen, 34.69 percent of the potash and 59.32 per¬ 
cent of the phosphoric acid. 
In comparison with the losses from our manures, some in¬ 
stances of experiments at other Stations are here given, although 
it is a difficult matter to compare losses owing to the varying dura¬ 
tion of the experiments and methods used. 
Some Experiments at the Nezv Jersey Station. 
Dr. Voorhees in Bulletin 150 of the New Jersey Station, de¬ 
termined the loss sustained by ioo-pound lots of cow manure when 
exposed to the weather in layers eight inches deep in a special form 
of galvanized iron box. From four experiments with mixed solid 
