4o6 Journal of Agricultural Research voi. iv, No. s 



Sotgia (lo) reported an experiment on feeding prickly-pear to five 

 cows in Sardinia which indicated in general that the prickly-pear increases 

 the milk yield without lowering the percentage of solids in the milk. 



On the other hand, Mr. P. R. Mehta (9), Acting Deputy Director of 

 Agriculture, Bombay Presidency, India, in reporting the results of a 

 feeding trial conducted with five animals for five months in 1902, stated: 



The result of our extended and thorough trial proves conclusively that prickly- 

 pear has hardly any value as a cattle feed. It is only when given with a moderate 

 quantity of ordinary fodder that the animals can just manage to live for a period of 

 four to fave months. 



While these and other interesting and valuable observations on the 

 feeding of the plant have been made, it was thought advisable to obtain 

 more definite knowledge than is afforded by the ordinary feeding prac- 

 tice. Accordingly, the Dairy Division of the Bureau of Animal Industry, 

 cooperating wdth the Office of Farm Management of the Bureau of Plant 

 Industry, conducted the experiments herein reported at the South Texas 

 Gardens, Brownsville, from October, 191 1, to April, 1913. 



PLAN OF THE INVESTIGATIONS 

 CULTIVATION OF PRICKI^Y-PEAR 



The prickly-pears used in these experiments consisted of cuttings of 

 native species collected from uncultivated lands near Brownsville and 

 set out in the cultivated fields of the experimental farm. The stock 

 which it was thought would produce the largest yields was used in the 

 plantings. Three species common to the region were planted, O. gomtnei, 

 O. cyanella (color PI. F), and an unnamed variety. All were probably 

 confined in their distribution to the delta region of the Rio Grande. 

 Although these species differ botanically there is very little distinction 

 between their forage value and that of many other spiny species in 

 southern Texas, except that these delta species are the most viciously 

 spiny and the most difficult to singe. The difficulty in singeing is caused 

 mainly by the large number of coarse spines and the still larger number 

 of long, coarse spicules; and the region being near the coast, where the 

 atmosphere is humid, the spines of all species are less combustible. 



The two varieties named constituted probably 95 to 98 per cent of the 

 plantation. The third species differed from these in several particulars, 

 but more especially in its habit of growth. It is judged to be of less 

 value than either of the two others, mainly on account of its smaller, 

 thinner joints. However, this species did not form more than from 3 to 

 5 per cent of the field. 



The main crop of prickly-pear was planted in the spring about 18 

 months before the feeding was begun and consequently had had two sea- 

 sons' growth. As the feeding was continuous from the date of beginning, 



