12 BULLETIN 588, U. S. DEPARTMENT OF AGRICULTURE. 



2 to 12 months. All of the wells but one were constructed before the 

 range was reserved and are on private land. The pipe line was built 

 in 1916 and carries the water from several mountain springs, a dis- 

 tance of about 8 miles, to range difficult to provide with water by 

 any other means. At the same time it relieves the range and water 

 about the wells. One of the tanks was constructed in 1915 and five 

 during 1916 for the double purpose of getting the cattle nearer water 

 and relieving the range and water about the wells, springs, and 

 permanent tanks. 



Of the 15 tanks, one or more caught some of the run-off resulting 

 from practically every shower that fell on the Reserve in 1916. In 

 several instances this allowed the cattle to get onto fresh feed near 

 water and make good gains in condition and at the same time cut 

 down the expense of pumping and gave the hard-used range a rest. 



The cost of the five tanks constructed in 1916 was $787, which 

 includes a reasonable compensation for the use of horses and mules 

 employed in the' work. The cost per tank varied from $53.40 to $309. 

 The cost per cubic yard of earth in the embankment varied from 

 $0.42 to $1.^0, including time of travel between town and the tank 

 site. A large part of the higher cost was for such travel. Even at 

 this high cost the tank is considered a good investment, since it opens 

 up range hitherto little used. The smallest of the five tanks should 

 hold water at least two months after it is puddled and filled once; 

 and the largest about eight months. 



The range of the Reserve is now one of the best watered units in 

 southern New Mexico. On about 80 per cent of the area stock do 

 not have to travel more than 2|- miles to water. This will aid mate- 

 rially in carrying the stock through bad years with light losses and 

 in good years will permit of increasing the number of stock. Although 

 the pipe line and five new tanks were not available for use during the 

 dry season of 1916, the fact that the range was as well watered as it 

 was had its part in carrying the stock through with a loss of less than 

 1^ per cent for the year. 



Additional water will be developed, and careful observations will 

 be made with the idea of determining more conclusively the point at 

 which water development for a given type of range ceases to be a good 

 business investment. 



CARRYING CAPACITY. 



To decide the number of stock that a range pasture or large range 

 unit will carry year after year is one of the most difficult problems of 

 range management. Private pastures, as well as range lands, are 

 often overstocked and slowly depleted unintentionally through lack 

 of knowledge of their carrying capacity and the effect of the over- 

 stocking upon the forage production. The problem is complicated 

 by the following facts : 



