PRODUCING MARKET MILK IN EASTERN NEBRASKA. 7 
CREDIT FOR MANURE. 
The method used in these studies for obtaining the value of manure 
takes into consideration the fertilizing constituents of the feeds. 
The proportion of the fertilizing constituents of the feed that was 
returned in the manure was obtained from standard tables. A cow 
digesting her feed utilizes on the average approximately 25 per cent 
of the nitrogen, 30 per cent of the phosphorus, and 15 per cent of 
the potash contained in the feed. It is evident, then, that 75 per 
cent of the nitrogen, 70 per cent of the phosphorus, and 85 per cent 
of the potash is voided in urine or in the solid portion of the manure. 
The urine voided by a cow is more valuable than the solid manure 
as a source of nitrogen and potash. 
Table 4.— Manure and fertilizing constituents credited to the herds during the two winters 
and the two summers. 
Item. 
Winter. 
1917-18 1919-20 Average 
Summer. 
1918 1919 Average 
Total manure saved tons. . 
Manure per cow pounds. . 
Manure credited per 100 pounds of milk, 
pounds 
Fertilizing constituents in manure, 
pounds 
Credit per cow pounds. . 
979.1 
7,062 
234 
801.1 
7,289 
256 
890.1 
7,162 
244 
68.9 
532 
75.5 
647 
22 
72.2 
587 
20 
Winter average. 
Summer average. 
Nitro- 
gen. 
3,426 
33.9 
Phos- 
phoric 
acid. 
10.5 
Potash. 
Nitro- 
gen. 
3,753 
35.2 
Phos- 
phoric 
acid. 
210 
0.9 
Potash. 
710 
3.0 
The small credit for manure (Table 4) is due to a combination of 
factors. During the summer the cows are in the barn just long 
enough to be milked. Only during very cold or stormy days in 
winter are the cows kept in the barn. On other days they are per- 
mitted to run in the stalk fields, where they pick up a little corn and 
such roughage as they can find. On many farms a considerable 
quantity of the manure voided in the barns, especially the liquid 
portion, was lost through leaky gutters. When it was stored in 
the yards before being spread on the fields a large percentage of the 
fertilizing value was lost through seepage and exposure to the weather. 
Only the manure that was dropped directly on the stalk fields, or 
was saved, or could have been saved by using reasonable care with 
the equipment available, was credited to the cows. The quantity 
of manure dropped was approximated by keeping a record of the 
time the cows were actually in the barn. This made it possible to 
