64 BULLETIN 1031, U. S. DEPARTMENT OF AGRICULTURE. 
Constant use of the better methods should result in a calf crop 
of not less than 70, or more nearly 80, calves per 100 cows each year 
on the ranges of the Southwest, instead of the usual 50 or 60 calves 
under present methods. So great an amount as $3.87 per cow per 
year for feed and provision of adequate winter and spring range, 
as well as the small additional expense for proper bull distribution, 
are warranted when they affect calf crops so materially. Four bulls 
per 100 cows are insufficient unless stock are handled in small lots 
during the breeding season, and bull distribution is attended to by 
range riding on large ranges. With expensive, high-class bulls, 
fencing to control stock on small areas and riding to distribute bulls 
will doubtless be found more economical than the use of more bulls. 
Segregation of breeding stock from nonbreeding stock is of im- 
portance in obtaining better bull service and should not be lost sight 
of in efforts to obtain more calves per 100 cows. In addition, it is 
probable that heifers under 20 months of age should not be bred 
under southwestern range conditions, as they usually skip the fol- 
lowing year or require additional feed to prevent stunting. After 
a cow passes 11 or 12 years of age she usually begins to decline in 
productiveness and there is danger of heavy expense in feeding her 
through the spring, so that it is best to dispose of cows when they 
reach this age. 
FUTURE PLANS FOR INCREASING THE CALF CROP ON THE JORNADA RANGE RESERVE. 
The results to date’on the Jornada Range Reserve justify con- 
tinuing the methods of management and even intensifying them. 
In the future it is planned to increase feeding in the various herds 
to where all stock will be in better breeding condition, and also 
eventually to divide the range for the main herd so that the cows 
will be confined in a smaller area during the main breeding season, 
and in this way insure better bull service, as well as provide fresh 
range for winter. The herd of approximately 500 head will be 
handled much the same as previously, with more riding to keep bulls 
distributed. The herd of less than a hundred head will be continued 
in order to secure more conclusive data on the value of small herds. 
To determine the effect of breeding heifers to calve at 2 years of 
age, 95 yearling heifers were placed in a separate pasture and bred 
in 1919. Careful records will be made of the number of calves 
dropped, rate of growth of calves and heifers, and cost of feeding 
each year. They will be compared with a number of heifers not 
bred to calve until 3 years cf age. Records for the two herds will 
be maintained long enough to obtain data as to the effect over a 
period of breeding heifers to calve at 2 years, compared to breeding 
them to calve at 3 years of age. 
