FARM MANAGEMENT PRACTICE OF CHESTER COUNTY, PA. 93 
TasLeE LIV.—Amount of silage raised and fed per head of cattle on owner farms, 
Chester County. 
Num- 
Aver- 
Aver- Num- | ber of 
oY ore age Aver- NBR ber of | tons 
Num- | yim- | 2@2- lamount| raised | ,tons_| raised 
Number of cattle. ber of ber fed per | for feed} Loss. 
ber of fed per | for feed 
farms days Al year per 
| cate feeding coup Pll Bere) |aper.” I year 
units p ead. er 
silage.® need p | head. ie 
Pounds.| Pounds. (Pect 
IL iO TAC ee ee pace mise aes acer seaareet 5 9 200 38 5 3.80 5.30 28.3 
DSU ORDA ee ere Sere eres eee a eras ee aS 26 20 192 43 45 4.13 4.32 4.4 
DOMLORGA eee cle Mae mo oa ase, sue 16 29 224 32 36 3.58 4.03 eZ, 
BUPA GHOVOLS st ws) sialic ene Se 9 50 212 45 50 4.77 5.30 10.0 
a Figured on basis that 2 head of young stock = 1 cow, bull, or steer. 
b Answers by letter from 24 farmers. 
On account of the manner in which this estimate was obtained, the 
figures here given can only be considered a first approximation at 
this loss. It should be stated, however, that this estimated loss of 
i3 per cent is in close agreement with the rather meager chemical 
investigations of the subject. 
It is worthy of note that the largest losses occur on those farms 
feeding the smallest number of cattle. Unless there are cattle enough 
to consume the entire surface layer of silage to a depth of several 
inches daily, there is a good deal of loss from decay of silage left too 
long in contact with the air. 
The average number of tons of silage stored per head of stock 
to be fed is seen by Table LIV to be 43. The actual amount fed 
appears to be about 4 tons per head in 63 months. The common 
practice here is to feed silage during the winter, and during periods 
of the summer when pastures are short. 
RATE OF DEPRECIATION OF DAIRY COWS. 
The data obtained in this survey make it possible to calculate the 
rate of depreciation on dairy cows, as well as on farm horses. The 
rate thus obtained does not, however, represent the annual rate at 
which an animal deteriorates after it passes its prime, for as the 
calculation is here made the depreciation of such animals is in -part 
cancelled by the increase in value of animals before they reach their 
prime. But the rate here obtained does represent approximately 
the average charge which must be made for depreciation in deter- 
mining the cost of maintaining the dairy herd. The method. of 
calculation is shown in detail in Table LV. This method may be 
applied to an individua! herd of cows, as well as to the average of a 
large number of herds. 
1See Henry’s Feeds and Feeding, edition of 1898, p. 246, where this loss is given as 
10.8 to 20.0 per cent. 
