207 
 
 U. S. DEPARTMENT OF AGRICULTURE. 
 
 BUREAU OF PLANT INDUSTRY— BULLETIN NO. 124. 
 
 B. T. GAhLOWAWChief of Bureau. 
 
 THE PItlCKLY PEAR AS A FARM ' 
 
 DAVID GRIFFITHS, 
 Assistant A(H{Ioui-ti'ri8t. Fakm MANAGEMEisfT Investigations. 
 
 Issued FF.niaiAKv 1!>, UM»S. 
 
 WASHINGTON: 
 
 GOVERNMENT PRINTING OFFICE. 
 
 1908. 
 
 %m0 
 
2.QJ 
 
U. S. DEPARTMENT OF AGRICULTURE. 
 
 It 
 
 BUREAU OF PLANT INDUSTRY— BULLETIN NO. 124. 
 
 B. T. a ALLOW AY, Chief 0/ Bureau. 
 
 THE PRICKLY PEAR AS A FARM CROP. 
 
 DAVID GRIFFITHS, 
 Assistant Agkiculturist, Farm Manacjement IxvESTioATiONa. 
 
 Issued Feukuary lU, 1908. 
 
 WASHINGTON: 
 government printing office. 
 
 1908. 
 
BUREAU OF PLANT INDUSTRY. 
 
 Pathologist and Phi/sioJoyist, and Chief of Bureau, Beverly T. Galloway. 
 
 Pathologist and Phiisiologist, and Assistant Chief of Bureau, Albert F. Woods. 
 
 Lahoratorii of Plant Pathology, Erwin F. Smith, Pathologist in Charge. 
 
 Investigations of Diseases of Fruits, Merton B. Waite. Pathologist in Charge. 
 
 Laboratory of Forest Pathology, Haven Metcalf, Pathologist in Charge. 
 
 Truck Crop Diseases and Plant Disease fiurvey, William A. Orton, Pathologist in Charge. 
 
 Plant Life History Investigations, Walter T. Swingle, Physiologist in Charge. 
 
 CgtTon Breeding Investigations, Archibald D. Shamel and Daniel N. Shoemaker, Physiolo- 
 gists in Charge. 
 
 Tobacco Investigations. Archibald D. Shamel, Wightman W. Garner, and Ernest H. 
 Mathewson, in Charge. 
 
 Corn Investigations, Charles P. Hartley. Physiologist in Charge. 
 
 Alkali and Drought Resistant Plant Breeding Investigations, Thomas H. Kearney, Physi- 
 ologist in Charge. 
 
 Soil Bacteriology and Water Purification Investigations, Karl F. Kellerman, Physiologist 
 in Charge. 
 
 Bionomic Investigations of Tropical and Subtropical Plants, Orator F. Cook. Bionomfst 
 in Charge. 
 
 Drug and Poisonous Plant Investigations and Tea Culture Investigations, Rodney H. 
 True, Physiologist in Charge. 
 
 Physical Laboratory, Lyman J. Briggs, Physicist in Charge. 
 
 Crop. Technology and Fiber Plant Investigations, Nathan A. Cobb, Crop Technologist in 
 Charge. 
 
 Taxonomic and Range Investigations, Frederick V. Coville, Botanist in Charge. 
 
 Farm Management Investigations, William J. Spillman, Agriculturist in Charge. 
 
 Grain Investigations, ^lark A. Carleton, Cerealist in Charge. 
 
 Arlington Erperimcntal Farm, Lee C. Corbett, Horticulturist in Charge. 
 
 Vegetable Testing Gardens, William W. Tracy, sr., Superintendent. 
 
 Sugar-Beet Investigations, Charles O. Townsend, Pathologist in Charge. 
 
 Western Agricultural Extension Investigations, Carl S. Scofleld, Agriculturist in Charge. 
 
 Dry-Land Agriculture Investigations, E. Channing Chilcott, Agriculturist in Charge. 
 
 Pomological Collections, Gustavus B. Brackett, Pomologist in Charge. 
 
 Field Investigations in Pomology, William A. Taylor and G. Harold I'ovvell, I'omologists 
 in Charge. 
 
 Experimental Gardens and Grounds, Edward M. Byrnes, Superintendent. 
 
 Seed and Plant Introduction, David Fairchild, Agricultural Explorer in Charge. 
 
 Forage Crop Investigations, Charles V. Piper, Agrostologist in Charge. 
 
 Seed Laboratory, Edgar Brown, Botanist in Charge. 
 
 Grain Standardization, John D. Shanahan, Expert in Charge. 
 
 Subtropical Laboratory and Garden, Miami, Fla., Ernst A. Bessey, Pathologist in Charge. 
 
 Plant Introduction Garden, Chico, Cal., August Mayer, Expert in Charge. 
 
 South Texas Garden, Broansville, Tex., Edward C. Green, Pomologist in Charge. 
 
 Cotton Culture Farms and Farmers' Cooperative Demonstration Work, Seaman A. Knapp, 
 Lake Charles, La.. Special Agent in Charge. 
 
 Congressional Seed Distribution (Directed by Chief of Bureau); Lisle Morrison, Assistant 
 in General Charge. 
 
 r- r- n Editor, J. E. Rockwell. 
 
 'to 26 1903 Chief Clerk, James E. .Tones. 
 
 ^'ora,' 
 
 Farm Management Investigations. 
 William J. Spillman, Agriculturist in Charge. 
 
 Scientific Staff. — J. C. Beavers, G. A. Billings, D. A. Brodie, J. ^ Gates, J. S. Cotton, 
 H. R. Cox, M. A. Crosby. L. G. Dodge, J. A. Drake, L. W. Ellis, J. W. Froley. C. L. 
 Goodrich, David Griffiths. Byron Hunter, H. B. McClure, A. D. McNair, H. A. Miller, 
 W. A. Peck. C. E. Quinn, C. B. Smith, S. M. Tracy, J. A. Warren, B. Youngblood. 
 
 124 
 
.ETTER OF TRANSMITTAL. 
 
 TT. S. DRPART:\rENT OF Agricitlture, 
 
 Bureau of Plant Ixdustry, 
 
 Office of the Chief, 
 Washington, D. f'.. Decemhete, 1907. 
 Sir: T have tho honor to transmit herewith, and to recommend 
 for publication as Bulletin No. 124 of the series of this Bureau, a 
 manuscript entitled "The Prickly Pear as a Farm Crop," by Dr. 
 DaA'id Griffiths, which has been submitted by Prof. W. J. Spillman, 
 Agriculturist in Charge of Farm Management Investigations, with 
 a view to publication. 
 
 This is the first. report based upon actual experiments dealing Avith 
 the cultivation upon a field basis of any of the peculiar a]id interest- 
 ing plants laiown as prickly pears. They have been utilized to a 
 large extent in the economy of the stock business of southern Texas, 
 but have never before been cultivated as a field crop in this country. 
 The author desires to acknowledge his indebtedness in the conduct 
 of these investigations to the cooperation of Mr. Alexander Sinclair, 
 upon Avhose ranch the Avork is being carried on, and to his son, Mr. 
 William Sinclair, Avho has so faithfully cared for the plantation. 
 Respectfully, 
 
 B. T. Galloavay, 
 
 Chief of Bureau. 
 Hon. James Wilson, 
 
 Secretary of Agriculture. 
 
 124 3 
 
CONTENTS. 
 
 Page. 
 
 Introduction 7 
 
 Climatic conditions of tlie region 8 
 
 Preparation of cuttings of priclvly pear 10 
 
 Method of planting 12 
 
 Time of year to plant 14 
 
 Renewal of plantation 15 
 
 Cultivation , . 15 
 
 Time of harvesting •_ 10 
 
 Method of harvesting 16 
 
 Varieties to plant 18 
 
 Cost of planting 19 
 
 Spineless compared with spiny species 20 
 
 Quantity of feed produced by jH'ickly pears 22 
 
 Cultivation and noucultivation 24 
 
 Some effects of cultivation 25 
 
 Uses of the crop 20 
 
 Prickly pear compared with sorghum 27 
 
 Enemies of the prickly pear 28 
 
 Summary — 31 
 
 Description of plates 34 
 
 Index 35 
 
 124 5 
 
ILLUSTRATIONS 
 
 rage- 
 
 Plate I. Prickly pear experiments. Fig. 1. — Cultivated and nuculti- 
 
 vated prickly pear. Fig. 2. — Covering cuttings with a plow. 
 
 Fig. 3. — Cuttings distributed in furrow ready to be covered. 
 
 Fig. 4. — Cuttings distributed on the surface of the ground, 
 
 not to be covered 34 
 
 II. I'rickly pear experiments. Fig. 1. — Cattle grazing singed 
 prickly pear. Fig. 2. — Singeing prickly pear. Fig. 3. — Un- 
 cultivated plantation twenty years old. Fig. 4. — Cultivated 
 
 prickly pear two years old 34 
 
 124 
 
 6 
 
B. r. I.— 327. 
 
 THE PRICKLY FEAR AS A FARM CROP. 
 
 INTRODUCTION. 
 
 No attempts have been made hitherto to cuHivate prickly pear as 
 a resiihir crop in this country. The nearest approach to it was 
 made by some of the old mission fathers of California, who im- 
 ported cuttings, probably from Mexico, and planted them in hedges, 
 where they served the double purpose of barriers against stock and 
 as food for man. That they received any appreciable degree of 
 cultivation, however, is very doubtful. They were probably grown 
 in much the same manner that the so-called cultivated prickly pears 
 are grown in Mexico to-day. 
 
 An extended use has been made of the native crop at various times 
 for the past fifty years or more in southern Texas, but it has mainly 
 been spasmodic, lasting only until " the drought was broken," ex- 
 cept for sheep and goats, which are fed on it regularly, and in the 
 case of the few dairymen who have made it a practice to feed it for a 
 portion of each year. In short, the prickly pear has been con- 
 sidered an emergency feed, to be used only Avhen other feeds fail. 
 Even enthusiastic pear feeders in Texas thought that the results to be 
 obtained from planting and cultivating an experimental tract would 
 only be " very interesting." There was little expectation that the 
 plants would respond to cultivation as they have done. The facts 
 presented in this paper, however, show that the prickly pear will 
 produce, under proper cultural methods similar to those used for the 
 common staple crops, yields of roughage superior to some of the 
 standard agricultural crops of the region, especially when an otf 
 3^ear occurs. It has proved itself under cultivation not only an 
 emergency feed but an insurance against famine, as well as a plant 
 which can be grown and depended upon regidarly as a farm crop. 
 
 The investigations of this subject at the present time are very 
 opportune indeed, because the demand for such a crop is not as great 
 in southern Texas now as in a thickly settled region, giving ample 
 time for growers to learn just the position that the crop should 
 occupy in the economy of their operations. Land is still changing 
 
 22052— Bui. 124— OS 2 7 
 
8 THE PRICKLY PEAR AS A FARM CROP. 
 
 hands in southern Texas in 200-section blocks, and all of it has 
 more or less prickly pear growing upon it. It is not to be expected 
 that holders of such areas will be concerned with the culture of 
 prickly pear any more than they will be concerned with the culture 
 of any other crop, for they have plent}^ of pear growing wild in 
 their pastures now. often more than they can possibly use. Settle- 
 ment and subdivision of holdings are taking place very rapidly, 
 however, throughout the region, and the time is not far distant 
 when the whole counfry will be divided up into small holdings where 
 the small farmer will depend upon a variety of crops and where use 
 will be found for a crop like this which can withstand a protracted 
 drought of two or three months or more without artificial irrigation. 
 
 Indeed, many large communities now exist which need to grow 
 sdme crop of this kind. In the vicinity of the larger cities dairymen 
 have for years been in great need of roughage ' upon which they 
 can depend, as well as succulent feed, which is not usually available 
 during one-half of the year. In the vicinity of San Antonio, Tex., 
 the feeding of the prickly pear has been so extensive during the past 
 six years that the pastures have been practically depleted of it 
 Avithin a radius of eight miles from the city. Still, the hauling of 
 the crop such distances is doubtfully profitable, especially when it 
 must now almost invariably be paid for. When it is remembered 
 that a cow will eat in the neighborhood of 100 pounds a day, it will 
 be readily understood that to haul pear such distances for feed is 
 very burdensome. These dairymen could much better afford to turn 
 some of their native brush pastures into cultivated fields of prickly 
 pear, wherein they could feed the crop with no handling and be 
 insured against a shortage of roughage. The conditions around San 
 Antonio are practically duplicated near Laredo. 
 
 Attention should be called here to the fact that this report applies 
 to the experiments conducted at San Antonio only and that the terri- 
 tory to which the experiments apply extends, roughly, from Houston 
 to Del Rio and from Austin to Brow^nsville. Investigations along 
 similar lines are being conducted in New Mexico, Arizona, California, 
 and Florida, but it is not time to report upon them yet. 
 
 CLIMATIC CONDITIONS OF THE BEGION. 
 
 According to Bulletin Q. " Climatology of the United States," 
 issued by the United States Weather Bureau, the mean annual pre- 
 cipitation for the city of San Antonio for the past eighteen years 
 has been 28.4 inches. The total amount for the driest year for the 
 same period was IT). 9 inches, and the total for the wettest. year, 40.5. 
 These figures are very important in the interpretation of these inves- 
 tigations and show that the work is being done in a region of rela- 
 tively high average annual rainfall. These tables do not, however, 
 
 124 
 
CLIMATIC CONDITIONS OF THE REGION. 
 
 9 
 
 tell the whole story. It is necessary to study the monthly totals in 
 order to appreciate the conditions of moisture prevailino-. The fol- 
 lowing table is compiled from monthly totals of precipitation for 
 the past ten years and shows in a striking way how irregular is the 
 distribution of moisture: 
 
 Table I. — Monthly totals of precipitation for Sian Antonio, Tex., for the ten years 
 from 1897 to 1906, inclusive, in inches. 
 
 Month. 
 
 1897. 
 
 1898. 
 
 1899. 
 
 1900. 
 
 1901. 
 
 1902. 
 
 1903. 
 
 1904. 
 
 1905. 
 
 1906. 
 
 Monthly 
 extremes. 
 
 January.. 
 
 1.59 
 
 1.') 
 
 1. 1)."-) 
 
 1.84 
 
 3.1.3 
 
 2.19 
 
 .28 
 
 .40 
 
 l.(il 
 
 1. 3.') 
 
 .43 
 
 1.34 
 
 0.46 
 1.16 
 1.47 
 1.46 
 1.06 
 7.06 
 2.24 
 3,35 
 1.32 
 .03 
 1.34 
 1.54 
 
 0.38 
 
 .31 
 
 *T. 
 
 2.60 
 
 2.22 
 
 4.32 
 
 2.85 
 
 .00 
 
 ..57 
 
 1.31 
 
 1.70 
 
 3.39 
 
 5.42 
 
 .34 
 4.34 
 9.11 
 4.47 
 
 .78 
 2.24 
 4.05 
 
 .97 
 2.94 
 1.82 
 
 .70 
 
 0.41 
 
 .71 
 
 .54 
 
 .59 
 
 2.47 
 
 1.86 
 
 3.79 
 
 .96 
 
 4.20 
 
 :S 
 
 .,5 
 
 0.70 
 
 .55 
 
 .12 
 
 2.31 
 
 3.14 
 
 .02 
 
 3.85 
 
 .00 
 
 5. .52 
 
 2.54 
 
 3.53 
 
 2.51 
 
 2.39 
 
 7.88 
 
 1.29 
 
 1.74 
 
 1.95 
 
 4.75 
 
 7. .52 
 
 .20 
 
 2.96 
 
 1.61 
 
 *T 
 
 .82 
 
 0.30 
 
 .64 
 
 .16 
 
 3.25 
 
 5. 93 
 
 1.73 
 
 3.50 
 
 1.97 
 
 7.74 
 
 2.86 
 
 .24 
 
 1.06 
 
 0.88 
 1.62 
 2.74 
 6.08 
 4.11 
 6.01 
 2.82 
 .51 
 1.80 
 1.83 
 2.63 
 1.56 
 
 0.29 
 1.07 
 1.29 
 3.94 
 .86 
 .62 
 4.34 
 2.25 
 1.74 
 1.09 
 1.33 
 1.60 
 
 0. 30 to 5. 42 
 
 . 15 to 7. 88 
 
 March ■ 
 
 April 
 
 *T. to 4.34 
 ..59 to 9. 11 
 
 May 
 
 June 
 
 July 
 
 1. 06 to 5. 93 
 . 02 to 7. 06 
 . 28 to 7. 52 
 
 
 . 00 to 4. 05 
 
 
 . 57 to 7. 47 
 
 October 
 
 . 03 to 2. 94 
 *T. to 3. .53 
 
 
 .15 to 3. 39 
 
 
 
 
 
 
 
 *T.= 
 
 trace 
 
 
 
 
 
 
 
 With an equitable distribution of the rainfall there would be less 
 demand for a crop whicli can withstand periods of drought. 
 
 The column showing monthly extremes in the table above is most 
 striking; only three months ha^•e a minimum of more than one-half 
 inch. A glance at the columns of monthly totals will show nearly as 
 striking variations for the seasons. Even this table does not tell the 
 complete story. One must take into consideration the torrential 
 character of the summer rains. A rainfall of 4 inches is not at all 
 uncommon and may occur over a very local area. 
 
 These are the moi.sture conditions especially adapted to the suc- 
 cessful growth of prickly pear. Attention is called to this especially 
 because of the apparently well-established idea in the popular mind 
 that the plants will grow with little or no water — i. e., are adapted to 
 any desert condition. On the contrary, they are adapted to grow 
 where the rainfall is considerable but irregularly or periodically dis- 
 tributed. These plants can not grow without water any more than 
 any others, but they can get along for long periods without it on 
 account of the large quantities which they store up in their succulent 
 tis.sues. 
 
 As regards temperature « we are concerned with this crop mainly 
 in the minimum. The lowest temperature recorded by the Weather 
 
 "The records are all compiled from the United States Weather Bureau 
 records in the city of San Antonio, which are not perfectly satisfactory for our 
 station, because it is not only 8 miles distant, but 70 feet above the ground, 
 and consequently may not represent conditions where the plants grow within 
 several degrees. These records, however, are the only ones available. 
 124 
 
10 
 
 THE PEICKLY PEAR AS A FARM CROP. 
 
 Bureau for the San Antonio station is 4° F. in February. 1899, at 
 which time, according to the best information obtainable, pear as 
 well as the huisache {Acacia farnesiana) was badly frozen all over 
 southern Texas. This is an unusual temperature and has occurred 
 but once since the establishment of the station. The minimum in 
 1905, the lowest since these investig-ations were begun, occurred on 
 February 13. when a temperature of 13° F. was reached. Even this 
 was considered an unusually cold season. At this time the native 
 prickly pear appeared to be near the limit of its perfect endurance. 
 A few plants in the open drooped a little, but no permanent injury 
 was done, as they straightened up again in a short time. The mini- 
 mum Fahrenheit readings recorded for San Antonio for ten consecu- 
 tive years, beginning with 190G, are as follows: 24°, 13°, 22°, 19°, 26°, 
 15°, 19°, 4°, 20°, 18°, 27°, and 11°. But even these temperatures are 
 of short duration. It is seldom that seven days occur during an 
 entire Avinter with an absolute minimum below 22° F. Winters are 
 rather frequent when this temperature is not reached. 
 
 Besides a minimum not lower than something like 12° F. a high 
 average summer temperature is an advantage in the culture of 
 prickl^y pear. During the ten years ending in 1903 there occurred 
 on an average only four days a year with a maximum over 100° F. 
 One year of this period had twelve days with a maximum above 100° 
 F. and one year's maximum did not reach 100° F. The conditions 
 in this respect are presented in the following table : " 
 
 Table II. — Mnj-imum, minimum, and mean t r m peraturcM at San Antonio, Tex., 
 for a period of eighteen and one-half years. 1888 to .1906, inelusive. 
 
 Month. 
 
 January. 
 February 
 March . . . 
 April . . . 
 
 May 
 
 Juiie 
 
 Mean. 
 
 Maxi- 
 
 Mini- 
 
 
 mum. 
 
 mum. 
 
 op 
 
 °F. 
 
 °F. 
 
 52 
 
 82 
 
 6 
 
 55 
 
 90 
 
 4 
 
 62 
 
 97 
 
 21 
 
 70 
 
 99 
 
 35 
 
 .75 
 
 97 
 
 44 
 
 " 
 
 103 
 
 54 
 
 Month. 
 
 July...... 
 
 August... 
 September 
 October. . . 
 November 
 December. 
 
 Mean. 
 
 Maxi- 
 
 
 mum. 
 
 op 
 
 °F. 
 
 83 
 
 106 
 
 83 
 
 103 
 
 78 
 
 100 
 
 70 
 
 97 
 
 60 
 
 90 
 
 55 
 
 86 
 
 Mini- 
 mum. 
 
 PREPARATION OF CUTTINGS OF PRICKLY PEAR. 
 
 When these investigations were begun certain conventional for- 
 mula^ for planting all species of cacti were more or less in vogue. 
 These were found in the practices of horticulturists and in pub- 
 lished reports, mainlj' of French investigators in northern Africa. 
 These practices, briefly summarized, related mainly to propaga- 
 tion from cuttings. It has been the custom among horticulturists, as 
 well as the practice of the growers mentioned above, to prepare the 
 
 " See also discussions of temperature on page 21. 
 
 124 
 
PREPARATION OF CUTTINGS. 11 
 
 cuttin<j!;8 some time, commonly two weeks, before planting them. In 
 other words, the joints were somewhat wilted before being planted. 
 This practice appears to be necessary under greenhouse conditions, 
 and growers in northern Africa seem to be quite insistent upon the 
 same practice for out-of-door culture. When planted under the 
 humid conditions of the greenhouse, cuttings are much more likely 
 to decay at the surface of the ground unless some of the moisture is 
 evaporated before the cut surface is put in contact with moist earth. 
 
 Prickly pear cuttings do not callous over and produce roots from 
 the cambium and buds as do cuttings from ordinary trees and shrubs, 
 but the cut surface heals over and roots are put forth from the 
 areoles which contain the spines. It is important to bear this in 
 mind in the propagation of the prickly pears. From the gi^eenhouse 
 standpoint it is necessary that the cut surface be thoroughly dried 
 before the cutting is set. 
 
 Some attention was paid to this practice when the first plantings 
 were made in the spring of lOO"). An attempt was made to prepare 
 the cuttings at least forty-eight hours before they were planted, but 
 it was not always done. Indeed, a considerable part of the planting 
 occurred immediately after the cuttings were prepared. No bad ef- 
 fect was observed from the practice followed, although some of the 
 cuttings were planted during a very wet season. Since that time no 
 attention has been paid to the wilting of the cuttings. 
 
 The practice has been to use one- joint cuttings almost entirely for 
 planting, and it is believed that this is the most advantageous, all 
 things considered, for conmiercial practice. The favorite instrument 
 for making the cuttings has been a hoe straightened out so that the 
 blade is in a straight line with the handle. This is used much as a 
 spade might be used for the same purpose. With this instrument the 
 whole plant is cut up, as nearly as is convenient, into individual 
 joints. Of course it is not always convenient or even possible to 
 strike the union between the joints exactly, but this is approximated 
 as closely as possible. Sometimes the instrument severs one side or 
 the other, but this appears to make little difference, if any. 
 
 When the 6 acres of ground were planted in the spring of 1907, it 
 was done with the avowed purpose of performing the work as it was 
 considered the practical farmer or dairyman would carry it on. It 
 was the intention to get as practical a test as possible. The plants 
 after being brought to the field were cut up into single joints mainly 
 by the writer, but the hauling and distributing of the cuttings were 
 done principally by negro and Mexican labor. The handling was 
 done entirely with pitchforks, and the laborers were not cautioned at 
 all about being careful not to injure the stock. As a result, practically 
 every joint planted upon the entire 6 acres had from one to a half 
 
 124 
 
12 THE PKICKLY PEAB AS A FARM CROP. 
 
 dozen tine holes in it. In spite of this, it is certain that at least 99 
 per cent of the cuttings grew. Indeed, the stand on all portions of 
 the field was practically perfect. 
 
 The above experience is cited to show that there is nothing im- 
 practicable in our method of rough handling of the cuttings, not as 
 a justification of such handling. The less injury the cuttings receive 
 the better they will grow and the more vigorous plants will they 
 make without doubt ; but it is by no means imperative that care to 
 the sacrifice of speed in handling should be indulged in. The cut- 
 tings will withstand quite rough treatment and still make good 
 plants, but they should not be unnecessarily bruised or mangled. 
 
 As has been stated, single-joint cuttings have been used as a rule. 
 Occasionally when joints were very small two of them have been 
 left attached. The whole plant has been used invariably. All the 
 joints appear to grow equally well, but large, heavy joints two 
 or more 3^ears old make much the best plants. Good plants are 
 always obtained from old woody stems, often six or seven years old. ' 
 These are also much less likely to be bruised and otherwise injured 
 in handling than the younger growth. 
 
 The ISIexican people who handle very small quantities commonly 
 plant two and a half to three joint cuttings. Their object is to get 
 fruit as early as possible. In the cultivation of their large tame 
 forms they are not concerned with the stock-feed side of the question. 
 They claim to get a good crop of fruit the third year from such cut- 
 tings, while it would take five years to secure the same crop from 
 single-joint cuttings. Good crops of fruit have been secured from 
 single-joint cuttings of the native Opuntm lindheimeri in three years 
 in southern Texas. The large tame forms of JNIexico are much larger 
 plants, and it may consequently take them longer to come into bear- 
 ing. Indeed, none of them grown from single-joint cuttings along- 
 side of the Texas forms produced fruit in any quantity the third year. 
 
 METHOD OF PLANTING. 
 
 There are many points connected with the various operations of 
 planting, cultivating, and handling of these plants that have not 
 been fully demonstrated as yet. The best that can be done in con- 
 nection with some of these processes is to give an account of the 
 methods which have been used in these experiments. It is expected, 
 of course, that thes6 will be improved upon as our experience in 
 growing prickly pear becomes more extensive. 
 
 When the cultural Avork was taken up a 6-foot row was decided 
 upon as the most suitable. The distance between the cuttings in the 
 row has been varied from 2 to 4 feet. Although plantings have been 
 made for the purpose of determining which is the best distance, 
 
 124 
 
METHOD OF PLANTING. 13 
 
 still it is not possible to make ai\y definite recommendations at the 
 present time any more than to say that close planting appears to be 
 more productive in a general way than the more distant planting. 
 So thoroughly did this appear to be the case in our first experiments 
 that the entire G acres planted in the spring of 1907 had cuttings 
 planted 2 feet apart, from center to center, in 6 or 8 foot rows. 
 
 It is recommended to those who contemplate the cultivation of 
 this crop for forage in southern Texas that 6-foot rows be adopted 
 and that the cuttings be set 2 feet apart, from center to center, in 
 the row. This will enable one to cultivate one way for two seasons, 
 and the crop if harvested at the end of this time can be cultivated 
 again for the succeeding two seasons, when the second crop is being 
 grown, and so on indefinitely. It will be difficult to get a horse 
 through 6-foot rows after the second year. It is (juite possible that 
 further experience will demonstrate that other, distances will be 
 more advantageous. It may be that 2 feet apart in the row will 
 bring the plants too close together to produce the maximum yield, 
 or that the red spider will prove less injurious when the plants are 
 grown farther apart. These are questions which will require prac- 
 tice to fully demonstrate. At present it appears that 2 by 6 feet 
 is the proper distance. 
 
 The stock planted has been secured from native pastures within a 
 radius of 2 miles from the experiments. The plants cut olf at or 
 near the ground have been loaded on wagons with pitchforks. 
 Sometimes the larger plants have been cut up somewhat to facilitate 
 handling. Wngonloads of stock of this kind have been distributed 
 in the field in piles (see PI. I, fig. 3), which were subsequently pre- 
 pared for planting by cutting the plants into individual joints with a 
 hoe straightened upon its handle as described elsewhere. The cut- 
 tings were then distributed with a pitchfork to the places where 
 they were to grow. IMuch labor can be saved by a careful distribu- 
 tion of the material so that it need not be carried far. 
 
 Several methods of setting the cuttings have been tested. In 
 the earlier plantings some were set on edge in furrows or in holes 
 opened up with a shovel. This hand labor Avas very expensive 
 and troublesome, and it was soon recognized that it would not do 
 for commercial practice. In the last plantings made the cuttings 
 w6re not touched by hand at all. A portion of the 6-acre tract 
 planted in 1907 was laid out in rows by running a shallow furrow 
 with a small walking plow. The cuttings were laid against the 
 furrow, the base reaching nearlj^ to the bottom of the depression 
 (PI. I, fig. 3). Another furrow was then turned in the same di- 
 rection, throwing dirt over the bases of these joints, covering ap- 
 
 124 
 
14 THE PEICKLY PEAR AS A FARM CROP. 
 
 proximately one-half of them, sometimes more and sometimes less." 
 (PI. I, fig. 2.) Another portion of the field was simply marked and 
 the joints were laid on the surface of the ground at proper distances 
 in the rows thus laid out. (PI. I, fig. 4.) 
 
 When the ground is very dry, cloddy, or otherwise poorly pre- 
 pared, it will be advantageous to partially cover tjie cuttings; but 
 if the ground is well pulverized and in such condition that mois- 
 ture will be brought to the surface by capillarity, just as good 
 results will be secured by simply placing the cuttings on their 
 sides in firm contact with the ground. Indeed, in the first plantings 
 better plants were secured in this way than when the joints were 
 planted on edge. 
 
 Thei-e is good reason for this. Attention has been called to the fact 
 that roots spring from the areoles or cushions of spines and spicules 
 distril)uted regularly over the surface of the stems (joints). This 
 statement is equally true of the new growth. It always springs from 
 these areoles, but these spaces are always more numerous around the 
 edges of the disk-like cuttings. When the cuttings are laid flat on the 
 ground it is but a short time before unequal evaporation from the 
 two surfaces causes them to. dish slightly. This will leave the areoles 
 in the center of the lower surface in contact with the ground. They 
 will form roots in a very short time. From any portion of the 
 slightly upturned edge of the joint new growth may take place. In 
 the case of joints buried 6 inches or more by the plow, or otherwise, 
 the surface for ne.w growth is reduced at least by one-half and the 
 base or foundation of the plant is also reduced, or, more properly, is 
 much smaller than Avhen the cutting is laid flat and the whole edge is 
 in position to send out new growth. 
 
 It is very fortunate that the plants grow readily in this position, 
 for planting in this way greatly reduces the labor involved. Usually 
 all that is necessary is to drop the cutting into place from the fork. 
 At other times it may be necessary to press it down with the foot or 
 a slight pressure of the fork after it is in place. It should be borne 
 in mind that the cuttings should be in contact with the ground. If 
 they are held away from it an inch or so by clods, or even by the long, 
 stout spines found in some of the varieties, the chances of their be- 
 coming established are greatly reduced. Indeed, if none of the are- 
 oles is in actual contact with moist earth the cuttingSvwill not grow. 
 
 TIME OF YEAR TO PLANT, 
 
 There are indeed few, if any, crops which have such a range of 
 adaptability as regards the time at which they may be planted. Be- 
 
 o Care must be taken not to cover the joints, for they will almost invariably 
 rot if this is done. 
 124 
 
CULTIVATION. 15 
 
 ginniiiir with February, 1905, plantings were made between the first 
 and tenth of each calendar month, except August, for the next twelve 
 months, to determine, if possible, the most favorable season. No 
 plantings were made in August because it was excessively dry and 
 hot, similar to July, when cuttings failed to grow. .VU other plant- 
 ings iXYQw as well at one season of the year as another. All of the 
 plantings, except a part of those made in F'ebruary, were upon uncul- 
 tivated ground, the joints being placed in a furrow and partially 
 covered, as described elsewhere. This feature is again a decided 
 advantage, for it enables the farmer to plant this crop at almost any 
 time of the year. In other words, it can be done during a season 
 when other farm operations are not pressing. There is little doubt 
 tliat cuttings will grow even in July and August, provided those 
 months happen to be sufficiently moist. 
 
 RENEWAL OF PLANTATION. 
 
 Little is known about the length of time during which a plantation 
 will grow when repeatedly harvested in a systematic manner. Xo 
 reliable data are available. The nearest approach is in the case of 
 the planting made by Mr. D. M. Poor (PI. II, fig. H). This planta- 
 tion, consisting of two-thirds of an acre, was established by Mr. Poor 
 about 188;"). He laid off the gi'ound in rows 2 feet apart, with an 
 ordinary tAvo-horse plow, in land which had been cleared of brush 
 but never broken. Native pear was chopped up into one or two 
 joint cuttings, distributed in the furrows, and subsequently partly 
 covered with another furrow. The area has been used more or less 
 for twenty years, but it has never been cultivated. It has never been 
 harvested closely and certainly never systematically. 
 
 A plantation well established and cultivated is good for an indefi- 
 nite period, say fifteen or twenty years.' Should plants in various 
 portions of the field die for some reason, it is a very simple matter to 
 establish new ones when the crop is on the ground. All that is neces- 
 sary is to cut off a joint and put it in the proper place flat on the 
 
 ground. 
 
 CULTIVATION. 
 
 Upon the subject of cultivation little need be said. The ground to 
 receive tlie cuttings should be well and deeply prepared, and subse- 
 quent cultivation should probably be shallow, for the plants are shal- 
 low rooted. There are no cultivators known which are exactly suited 
 to this crop. In the experimental work described in these pages an 
 ordinary one-horse spike-tooth cultivator has been employed. The 
 ()!)jection to this implement is that the framework is too large, inter- 
 fering with the projecting branches of the plant, and also it is not 
 easily regulated as to depth. Some tool of the nature of a one-horse 
 22052— Bull. 124—08 3 
 
16 THE PEICKLY PEAR AS A FARM CROP. 
 
 sweep which could be regulated so as not to go into the ground much 
 more than 2 inches would be more serviceable. In the experimental 
 plantation it has been the endeavor to cultivate just enough to 
 keep down the weeds and prevent the ground from baking. To keep 
 down the Aveeds thoroughly it has been necessary to go through the 
 plantation occasionally with a hoe, knocking down such stray M^eeds 
 as the cultivator did not reach. 
 
 TIME OF HARVESTING. 
 
 It is not the purpose of this paper to attempt to say how often it 
 will be most profitable to harvest crops of prickly pear from estab- 
 lished cultivated plantations. Experience in this matter, as in many 
 others, has Ipeen too brief. All that will be attempted at the present 
 time is to state what can be done with one definite plan of cropping. 
 
 Prickly pear has been considered a slow-growing plant, and in- 
 deed it is a sloAv grower under natural conditions, where it is obliged 
 to compete with hardy grasses and other vegetation. In a previous 
 publication ° the opinion has been expressed that it will take five 
 years to produce a crop on uncultivated lands in the vicinity of Eagle 
 Pass, Tex., while in the same publication estimates made by ranch- 
 ers give the period as from two to three years. There appears to be 
 no reason at present for changing the first estimate for uncultivated 
 lands, while it has been demonstrated that a crop can be profitably 
 harvested in two years in cultivated plantations. Whether a pro- 
 portionately greater yield can be secured by allowing the plants to 
 grow three or four years has not been determined, but a paying crop 
 can be secured at the end of the second 3'ear, and probably can be 
 utilized at the end of eighteen months to good advantage if plantings 
 are made in February or March. The first harvesting done upon the 
 experimental tract was two years after planting. As shown in an- 
 other place, there was at that time more than sufficient roughage 
 upon an acre to feed two cows for one year. 
 
 But little fruit will be produced the first two years, but quite a 
 large crop will usually be secured the third 3^ear. 
 
 METHOD OF HARVESTING. 
 
 The different methods of preparing prickly pear for the use of 
 stock have been sufficiently discussed in other publications '' and 
 need not be repeated here. 
 
 In the singeing process economy depends largely upon the dispo- 
 sition of the plants. In the case of natural growth much time is 
 
 " Bulletin No. 74, Bureau of Plant Industry, " The Prickly Pear and Other 
 Cacti as Food for Stock," 1905. 
 
 ^ Especially in Bulletin No. 74 of the Bureau of Plant Industry, pp. 12-20. 
 124 
 
METHOD OF HARVESTING. 17 
 
 consumed in walkinif from 'one plant to another, because the phmts 
 are usually scattered over the field. Systematic plantinix economizes 
 both time and fuel. 
 
 In the harvestino; which has been done thus far upon the experi- 
 mental plantations the torch lias been used on standing plants, and 
 cattle have then been turned on to graze them (PL IT, figs. 1 and 2). 
 Others have been cut doAvn and hauled out of the field. This work 
 was done in the spring of 1907. In the autumn of the same season 
 little, if any, difference could be noticed between the growth made by 
 tlie plants harvested by the two methods. Those plants (grazed by 
 the cattle, however, were left in a very ragged condition and conse- 
 quently did not present so good an appearanc^. So far as growth is 
 concerned, however, it must .be admitted that grazed pear was nearly, 
 if not quite, as good as that which was cut down and hauled off. 
 
 There are several methods of harvesting open to the grower, two 
 of which have been mentioned here. Besides these methods the 
 plants may be cut down before singeing, and, if desired, two rows 
 may be cut into one center. The plants as they lie on the ground 
 may then be singed. Again the plants may be singed as they stand in 
 the row and then cut down, the cattle being allowed to graze them 
 where they fall. It is quite possible that the best method is the last 
 mentioned. 
 
 The singeing is done by pointing the blast flame downward in the 
 center of the plant, because in this Avay the maximum surface is 
 covered at one time by the flame. Afterwards the outer joints will 
 be touched by the blast. These processes can easily be regulated so 
 as to interfere but very little with the stump which is to be left stand- 
 ing. After the singeing the plants can be cut down and grazed Avhere 
 they fall. This will avoid leaving the stems partially chcAved and 
 macerated, in which condition they are more likely to decay and 
 result in injury to subsequent growth. Of course the plants can be cut 
 down before singeing, but the burning can not be done so advanta- 
 geously after the plants are felled. When standing, both sides of the 
 joints, which are in a more or less upright position, can be easily 
 reached with the fl.ame. while when felled the lower side in contact 
 with the ground can not be so easily singed. The two most impor- 
 tant requirements are economy of time and fuel and protection of the 
 stumps which are to produce future growth. These requirements 
 should be borne in mind constantly. Any process which economizes 
 time and fuel and does not injure the stem is the one to use. It 
 seems to the writer that singeing and then cutting the plants down to 
 be grazed Avhere they fall accomplishes this result best. 
 
 Iii some instances in the experimental investigations the harvesting 
 has been close, leaving nothing of the old plant but the original cut- 
 
 124 
 
18 THE PRICKLY PEAR AS A FARM CROP. 
 
 liii<>'. In other csises the harvestin"; has been done so as to leave all 
 the joints directl}^ attached to the original cutting. The latter plan 
 leaves a stump of two to four joints. If the plant was established 
 from a cutting laid on the surface of the ground, a large base and a 
 good surface for future growth to spring from will be secured. 
 There is no doubt that a large stump of this kind is an advantage; 
 neither is there much doubt that these old stumps will produce a much 
 heavier yield for the second biennial crop than is jDroduced from the 
 freshly established cuttings for the first crop. A considerably 
 heavier growth was secured during the season of 1907 from plants 
 having a stump of three or four joints from which to develop. 
 
 VARIETIES TO PLANT. / 
 
 In the southern Texas region there are several native varieties of 
 prickly pear, but in each locality there is usuallj'- one variety which 
 predominates. The very fact that it does predominate is fairly 
 good proof of its superior value for that locality. 
 
 In the vicinity of San 'Antonio the predominating variety is the 
 typical form of Oinintia lindhelnieri Englm., and this is the one 
 which is considered the best of all the forms for cultivation in this 
 immediate locality. Befoi-e any plantings were made upon the ex- 
 perimental tract a careful examination was made of the varieties in 
 the neighborhood, and this one selected is the most promising. Subse- 
 ([uent results — for other varieties were also planted for comparison — 
 confirmed the- first judgment. There is no (juestion that this is the 
 most valuable of all the forms and species used. It has prominent 
 and formidable spines, which turn white toward the end of the first 
 season's growth, and abundant light golden spicules." Another 
 native varietj'^ with a trifle darker color, less formidable spines, and 
 brown spicules has also made nearl}?^ as good growth and a much 
 heavier crop of fruit. This may prove valuable. From 150 to 200 
 varieties ha\e been planted. On the whole, none is to be recom- 
 mended above the spin}^ native just mentioned. Some of the vari- 
 eties planted, however, have characters which are decidedly ad- 
 vantageous. 
 
 One cultivated spiny form secured farther south is very promising 
 for breeding purposes. It has withstood the climate the first two 
 winters very well, but should another winter like 1901-5 occur it is 
 certain to suffer badly, for it was cut back very severely then in the 
 locality where secured. The spines on this one are not as formidable 
 as on the native form that is being grown, and the spicules are almost 
 
 "See Bulletin No. 91, Bureau of Animal Industry, 1!)00, pp. 0-11, for furtlioi' 
 notes on this species. 
 12-J 
 
COST OP PLANTING. 19 
 
 entirely absent on the joints. This variety has made a growth at the 
 rate of not less than 55 tons to the a^re per annum dnrino; the past 
 two years. 
 
 The prospective planter should study the plants in his locality 
 carefully before planting. He sliould select that form which makes 
 the largest and most rapid, clean growth, and from that variety he 
 should choose the most liealthy plants. Selection should be made 
 first for vigor and second with reference to tlie habit of the plant. 
 In southern Texas those forms growing most erect are to be pre- 
 ferred. In no case should a low, prostrate, or sprangling form be 
 used. As compact a growth as possible is desirable on accoimt of the 
 greater ease with which such forms are singed and cultivated. An 
 open-branching, low habit of growth renders the operation of culti- 
 vation very difficult on account of the interference of the branches, 
 with the animals and the machinery used in cultivation. 
 
 COST OF PLANTING. 
 
 During the spring of 1*.)()7 a careful ivcord was kept of the cost 
 of planting G acres of prickly pear upon the experimental ])lots. 
 Owing to the requirements of the farm, men could not be employed 
 regularly for full daj's on the planting and preparation of the 
 ground, but so far as the value of the record goes it is considered that 
 nothing is lo.st, for tlie time has been kept in hours for man and team. 
 
 The ground .selected had never. been plowed. It was in native 
 grass, closely pastured for sevei'al 3'ears, and had been grubbed 
 nearly clean of mescjuite and other brush years ago. The greater 
 part of the plowing and harrowing was done at odd times between 
 the 1st of January and the 1st of March. The season being very 
 dry considerable difficulty was experienced in getting the soil well 
 pulverized, and even the plowing was done with much difficulty. 
 
 The stock used for planting was .secured from various local .sources, 
 ranging from close by to 2 miles distant. The greater part of the 
 stock, although it was practically all of the .same variety, was hauled 
 from a neighboring ranch 2 miles away. Some Avas cut from a 
 pasture about half a mile distant, and about four loads from a 
 smaller experimental tract planted two years ago contiguous to the 
 present field. 
 
 The time employed in the va'rious planting operations, exclusive of 
 the preparation of the ground (plowing and harrowing), was as 
 follows : 
 
 Hours. 
 
 One man and team hauling stock (G acres) NH 
 
 One man and team marking (6 acres) and covering (3 acres) 14 
 
 One man distributing cuttings (G acres) "(4 
 
 The laborers used in hauling were negroes and Mexicans, and the 
 time was not employed to good advantage. It will be .seen froju the 
 
 124 
 
20 THE PRICKLY PEAR AS A FARM CROP. 
 
 above statement that the heaviest item of expense was for hanlinir 
 the stock for planting, which ought to have been done, even under 
 the disadvantages of distance, much cheaper. 
 
 Assuming the vahie of a man and a team at $3 and a man at $1 a 
 day of ten hours, the cost of planting an acre after the ground is 
 prepared is a little less than $6. If it is assumed that the value of 
 the preparation for planting is $3 an acre, then it costs about %^ an 
 acre to get the cuttings planted. With good labor advantageously 
 employed this expense could doubtless be reduced to $6 or $7 an 
 acre, but even at $9 the operation is not expensive when it is consid- 
 ered that a plantation is probably good for fifteen or twenty years 
 and that subsequent planting or establishing plants is a simple matter 
 when the material is on the ground and all that is necessary to estab- 
 lish a new plant is to la}^ a joint in firm contact with the soil. 
 
 SPINELESS COMPARED WITH SPINY SPECIES. 
 
 Much emphasis has been placed of late, esj)ecially in popular writ- 
 ings, upon the great advantages of spineless prickly pears. The 
 spines of these plants leave an unpleasant memory. They are diffi- 
 cult to handle, and the novice usually can not conceive how the 
 plants can be utilized at all on account of their formidable armament. 
 It naturally follows that if spineless forms can be substituted the last 
 objection to them has been removed. They could then be handled with 
 bare hands, and eaten as they grow b}' all kinds of live stock. So 
 firmly is the " spineless cactus " idea established in the public mind 
 that much talk has been made about establishing such forms, even on 
 the deserts^ supplanting the native forms and producing an abun- 
 dance of forage for live stock — this to be utilized without the singe- 
 ing process to which the native spiny forms must be subjected. 
 
 While such ideas are very interesting . and attractive, there are 
 many practical considerations which nnist be taken into account. 
 Of course, the expei'ience of the writer is as yet meager, these 
 experiments having been carried on only about four years. How- 
 ever, observation, together with three or four years' experimental 
 evidence, while not conclusive, points strongly to certain conclusions 
 which are not at all favorable to spineless forms for southern Texas, 
 for the immediate future at least. * 
 
 Thus far no spineless forms have been found which are hardy 
 under the conditions existing at San Antonio. The Avriter has 
 secured ten or twelve spineless forms from Mexico, and the Office 
 of Seed and Plant Introduction of the Bureau of Plant Industry 
 has imported for investigations as many more from Hawaii, south- 
 ern Europe, and northern Africa, all of which have been planted 
 and well cared for. All that are left of these spineless forms at the 
 
 124 
 
SPINELESS COMPARED WITH SPINY SPECIES. 21 
 
 present time are such individual plants as have been protected dur- 
 ing the winter. There' are a feAv nearly spineless forms here and 
 there in southern Texas, but so far as has been observed none of 
 them are quite hardy. They live through one or two winters all 
 right, but may be frozen down badly the third winter. The nearest 
 approach to hardiness that has lieen seen is in the city of Laredo, 
 Tex. There are here a few plants (nearly spineless) which often 
 pass the winter uninjured, but they were fro/en to sucli an extent in 
 February. 1004, that not less than one-half of the joints broke off. 
 Even these are not hardy upon the plantation at San Antonio and 
 probably would suffer nearly every winter at Laredo were the plants 
 there not protected by surrounding buildings. 
 
 Lack of hardiness I'cndei-s the spineless forms of no economic 
 value at the present time in southern Texas. If they can not with- 
 stand tlie winter temperature it is of course useless to plant them. 
 But while this is true it is not at all improbable that these smooth 
 forms may in time become very important and possibly entirely 
 supplant in culture those forms which are now being grown. The 
 bringing about of such a condition is, however, a long and tedious 
 process which will involve years of breeding in which the farmer 
 can usually take little or no part. Work along this line is now being 
 conducted for the benefit and use of the future, but present resvlts 
 must he secured from, spiny natives. Of course, in experimental 
 work sight is not lost of the fact that economic conditions may 
 change in the future so that it will be advisable to have spineless 
 forms, but the whole question is one of production. If spineless 
 forms which are hardy and which will produce moi-e feed than 
 spiny species which are now being grown can be evolved thev will 
 be valuable in proportion to the excess of feed which they will pro- 
 duce. This is as yet a purely experimental field, but the spiny native 
 varieties have been proved to be valuable. 
 
 Aside from lack of hardiness, the spineless prickly pears have 
 other disadvantages. Wherever grown they have to be fenced. It 
 will be obviously impossible to grow them in uncultivated pastures, 
 even in regions where they are hardy, for they would be grazed too 
 closely, if not exterminated in a very short while. Fences are expen- 
 sive. Unless the area planted to these forms were very large, Avhich 
 it could not be for some time, a rabliit-proof fence would be re- 
 quired. This sort of fence has been found necessary in order to 
 protect the varietal plantings made by the Bureau of Plant Industry 
 at San Antonio. Spineless forms would be severely injured by rab- 
 bits, gophers, and rats. The latter often do considerable injury to 
 the spiny native plants, but the spineless forms would suffer very 
 severely. A planting of about a hundred cuttings of imported varie- 
 
 124 
 
')9 
 
 THE PRTCKLV PEAR AS A FARM CROP. 
 
 lies, not all spineless, was completely destroyed in a fortnight by 
 ral)l)its in sonthern Arizona two years ago. When a hirge acreage 
 is j)Ianted the danger from these pests will not, of course, be so seri- 
 ously felt, but it will be many years before any extended plantings of 
 spineless forms can be made. There is not enough stock of spineless 
 prickly pears in this country at the present time to plant 5 acres if it 
 Avere all gathered into one place. 
 
 A plantation of spineless prickly pear ,would not only have to be 
 fenced, but stock could not be allowed to enter the field at any time 
 of the year, for they woidd trample over the entire field, knocking 
 down plants hither and 3'on and causing an unwarranted Avaste. 
 All of the crop would have to be harvested, loaded on Avagons. and 
 hauled to another lot to be feci. Tvemembering that 100 pounds a 
 day Avill be eaten by an average coav, it Avill be seen that this 
 procedure will mean considerable expense. In a 100-cow dairy 
 it Avill mean the moving of 5 tons of material for feed each day, 
 besides the removal of the manure. On the other hand, the spiny 
 forms, singed and fed Avhere they stand, obviate this expensive han- 
 dling and cause the manure for 100 coavs to be distributed each day 
 on about one-fifteenth of an acre — by no means a small item in main- 
 taining fertility. With spiny forms the number of plants fed or 
 grazed each day is absolutely Avithin the control of the rancher, e\'en 
 though stock is allowed in the field all of the time. 
 
 So far as southern Texas is concerned the advantages of the spine- 
 less and spiny prickly pears concerning Avhicli Ave have any knoAvl- 
 eclge may be summed up as follows: 
 
 Ad idiitdgcK! of sinin/ luitirc foruis. Advaiiidf/c.s of .s'/x'/ir/c.s.s- foiiiis. 
 
 1. They are bjirdy. 1. They do not require sui.Lceing. 
 
 2. They do not require fencinji. 
 ;>. They are injured but little hy wild 
 
 animals. 
 
 4. They require a niininnun of han- 
 dling. 
 
 n. They accomplish the distril)utif)n 
 of the manure duriui; tlic day. 
 
 QUANTITY OF FEED PRODUCED BY PRICKLY PEARS. 
 
 Our knoAvledge of the yield of prickly pear, either under natural 
 or cultivated conditions, is as yet quite imperfect, and the state- 
 ments made herein Avith reference to yields are made Avith such 
 reservation as is consistent with the meagerness of the evidence. 
 HoAvever, it is believed that all computations in Avhatever manner 
 made are exceedingly conservatiA'e, and miderestimate rather than 
 overestimate in every case what may be secured from a cultivated 
 crop of prickly pears. 
 
 124 
 
QUANTITY OF FEED PRODUCED. 23 
 
 The first plantings at San Antonio, and, indeed, the first attenipt 
 ever made in this country to cidtivate this phmt as food for stock 
 so far as the writer is aware, occurred in February, 1905. A plot 
 of ground 41G feet long and 208 feet wide (2 acres) was secured 
 under lease the preceding winter. Half of this area was plowed 
 and put in a good state of cultivation, the other half being left in 
 the condition in which it was found, i. e., in native sod, with all 
 brush removed. One half of the cultivated portion (one-half acre) 
 was reserved for varietal plantings and the other half was planted 
 to three or four varieties of native species, the typical O^nintia Jind- 
 heimeri predominating over all others. The whole area was laid off 
 into G-foot rows, numbered 1 to 69, and all plantings have been 
 made on this plan, variation being made in the distance apart of the 
 plantings in the row only. 
 
 Early in March, 1907, when the plantation was 2 years old, the 
 first harvesting Avas made. Xo weights were obtained except on a 
 small scale — too small, in fact, to make a reliable record, and conse- 
 quently need not be reported upon here. In one instance 75 head of 
 stock were turned in to graze off two i'oavs which had been singed. As 
 nearly as could be estimated this number of cows got from this small 
 area a full day's ration of roughage. There were some young cows 
 among them, and some which did not eat pear as freel}^ as they should, 
 but nevertheless they had been fed prickly pear regularly all the win- 
 ter and were still receiving it daily. Accepting the above as the 
 measure of the biennial production of forage of this plant under cul- 
 tivation, it will readily be appreciated that at this rate 2 acres of this 
 crop would, roughly, supply roughage for 75 cows for one month, 
 and 25 acres would, roughly, supply their needs for one year, but as it 
 took two years to grow this crop, on this basis it would require only 50 
 acres to furnish rough feed for 75 cows continuously. It is recognized 
 that this is a very crude and imperfect estimate of production, but it 
 is, nevertheless, instructive wlien taken in connection with wliat the 
 eye can see of the 2-37^ear-old crop shown in Plate II, figure 4. In or- 
 der to put the matter very conservatively, suppose this area was in- 
 creased 50 per cent : this would mean that 75 acres would furnish 75 
 cows with continuous roughage. This is still a production equaled 
 by that of few areas in the country. This quantity was produced 
 during one very favorable and one very unfavorable season and 
 probably represents about the average crop. 
 
 More definite data upon production were secured early in October, 
 1907, when the plantation was 31 months old. At this time two rows 
 were selected near the east side of the native plantings on cultivated 
 ground because they were thought to be typical of the half acre of 
 the cultivated native Opuntia Undheimeri. These rows were har- 
 
 124 
 
24 THE PRICKLY PEAR AS A FARM CROP, 
 
 A'ested down to the original cutting and weighed. These tAvo rows, 
 numbered 20 and 21 in the records, yielded 8,518 pounds. Rows 35 
 and 36 were then harvested, and weighed in the same manner. Row 
 36 was considered the poorest in the area. This was in part due to 
 its being in close proximity to uncultivated ground and in lesser part 
 to the ravages of the red spider. These rows were taken in order to 
 be certain not to overestimate the production. These two rows 
 yielded 7,269 pounds. On the four rows, therefore, there were pro- 
 duced 15,787 pounds. The area occupied by them measures three 
 twenty-sixths of an acre. The yield to the acre, consequently, was 
 136,820 pounds, or 68f tons. On account of the time of the year at 
 which the measurements were made it is rather difficult to reduce 
 this thirty-one months' growth into yearly terms, but if it is assumed 
 that three years' growth was secured an average yearly production of 
 22^ tons of green, succulent forage is shown. 
 
 This estimate of the average growth per annum of 224 tons is cer- 
 tainly conservative. It is evident that the growing season is not 
 closed the 1st of October, but, on the other hand, that a very decided 
 increase will occur between that time and Februarj^ Again, the 
 measurements were made at the close of a long dry season. It is quite 
 certain that the growth for the remaining five months, together with 
 the water absorption of the humid winter season, would be expressed 
 by tons to the acre. Besides this growth of plant body, there was 
 produced during the third growing season between 4 and 5 tons of 
 fruit to the acre. This fruit is greatly relished by horses, cattle, 
 sheep, and swine, and is harvested by them without assistance and 
 without injury <to the plants. 
 
 In feeding dairy cattle" at San Antonio it was found that a com- 
 plete roughage ration of prickly pear consisted of about 140 pounds 
 for each cow daily. In feeding steers for market at Encinal, Tex., an 
 average of about 75 pounds was eaten daily by each steer. These 
 figures would indicate that 100 pounds is about what the average ani- 
 mal will eat in a day. But the yields previously stated show that 
 sufficient roughage is grown here on an acre for about one and one- 
 fourth animals. 
 
 Any way it is figured, roughage of prickly pear for one mature 
 bovine animal on an acre seems to be a very conservative estimate. 
 
 CULTIVATION AND NONCTJLTIVATION. 
 
 At the same time that estimates were made of the rate of growth 
 on cultivated ground rows 37 and 38 were harvested. These were 
 
 grown without cultivation. As stated elsewhere, a furrow was opened 
 
 . , _» 
 
 « Bulletin No. 91, Bureau of Animal Industry, 1906. 
 124 
 
SOME EFFECTS OF CULTIVATION. 25 
 
 in the native sod, the joints hiid ai>ainst the hmd side, and the dirt 
 pulled back over their bases. The growth of pear on these tAvo rows 
 in thirty-one months weighed 980 pounds. This is at the rate of 
 8.49 tons to the acre. Eeducing this to terms of annual growth in the 
 same manner as was done in the other case, we have 2.83 tons to i:ep- 
 resent the growth per annum upon uncultivated ground; in other 
 words, eight times as much forage Avas produced under cultivation. 
 (See PI. I, fig. 1.) 
 
 The method of planting insured the rooting of the cuttings prac- 
 tically tlie same upon uncultivated as upon cultivated land. Practi- 
 cally ever}'^ cutting in either situation rooted and grew through the 
 period specified. , 
 
 It should be noted that the plantation is under fence. The 
 l)rickly pear upon the uncultivated ground, therefore, had to com- 
 pete with its full complement of grass growth. It would have 
 made a greater gain if the grasses were grazed off, as they commonly 
 are in the native pastures of the region. The figures showing the 
 relation of the production under the two conditions are conse- 
 (|uently not comparable with what would take place in pasture- 
 grown pear. Indeed, the growth in Mr. Sinclair's pastures just 
 outside of our fence was very much greater than that upon our 
 uncultivated area. This furnishes a very strong suggestion as to 
 the cause of the increase of prickly pear in some sections of south- 
 ern Texas since its occupation and settlement. Formerly, when 
 grasses were not grazed so closely, they were stronger competitors of 
 the prickly pears than they are now and Avere able to keep it in 
 check. Overgrazing, coupled with the prevention of fires, is doubt- 
 less responsible for the excessive growth of prickly pear in some 
 sections of the region. On the other hand, the rapid increase of 
 mesquite and other brush tends to check the growth of the pear, for 
 it does not thrive in the shade. 
 
 SOME EFFECTS OF CULTIVATION. 
 
 During the year 1907 the drouglit from June to October 1 was 
 much more pronounced than the average for this section. The 
 prickly pear in the pastures surrounding the experimental plantings, 
 as a consequence, was suffering considerably by the 1st of October. 
 Nearly all of it was somewhat shriveled, and in a few instances the 
 color had begun to change, showing the beginning of interference 
 with metabolism. Upon the cultivated area, on the contrary, the 
 long period with little precipitation had no apparent effect. All 
 plants were thrifty and vigorous. It is believed that no particular 
 nijury Avould have resulted if no rain had occurred for another three 
 months. 
 
 124 
 
26 THE PRICKLY PEAR AS A EARM CROP. 
 
 The effect of cultivation upon the development of spines is natu- 
 rally of some interest, and since the writer has often been questioned 
 regarding the comparative spininess of cultivated and uncultivated 
 plants, a few remarks upon the subject are made, with, however, no 
 attempt at any generalization. In the case of the typical form of 
 Ofuntia lindheimeri, which is being grown in the experiments, there 
 is a decided increase in spininess under cultivation. Indeed, the en- 
 tire plant looks somewhat different when cultivated; that is, a plant 
 under favorable conditions is just as different from a plant growing 
 under unfavorable conditions in this species as in the common culti- 
 vated crops. A comparison of Plate II, figure 3, with Plate II, figure 
 4, will tell better than words what the differences are. The first 
 is a view of the Poor plantation, which, although planted originally, 
 is in a practically native condition, for it was never cultivated. It 
 will be readily seen that the spines are fewer by several fold upon the 
 uncultivated plants. No quantitative measurements have ever been 
 made, and consequently only general statements are possible at this 
 
 time. 
 
 USES OF THE CROP. 
 
 A more or less complete discussion of the uses to which prickly 
 pear is put will be found in Bulletin No. 74 of this series, and a 
 further discussion of the value of the crop is contained in Bulletin 
 No. i)l of the Bureau of Animal Industry of this Department. 
 
 The crop appears especially adapted to dairy purposes because of 
 the comparative ease with which the ration can be balanced by the 
 addition of concentrates, which are used with all roughage in this 
 region. The succulence appears to be a decided advantage, and of 
 course can be obtained at any time of the year if the plants are 
 grazed where standing or are harvested as fed. The importance of 
 this can not be overestimated, for it applies to all seasons of the year, 
 and oftentimes green feed for dair}^ cattle is as difficult to secure in 
 the summer as in the winter. There is an impression in some sections 
 that this feed can not be used after the new growth starts in the 
 spring, but this is entirely disproved by the practices of several 
 ranchers who. have used it at all seasons of the year with good re- 
 sults. Of course there is a period during which the young growth 
 will not be eaten on account of its being distasteful to animals,*^ and 
 this growth will therefore be wasted at that time, but there is no 
 season of the year when pear will not be readily eaten, especially 
 if other feeds are short or dry. 
 
 It is very probable that the crop can also be used successfully for 
 the production of baby beef, as has been suggested Iw Mr. Sinclair, 
 
 " See Bulletin No. 91, Bureau of Animal Industry, 1906, p. 17. 
 124 
 
PRICKLY PEAR COMPARED WITH SORGHUM. 27 
 
 Avho has fed pear with as great success as anyone in southern Texas. 
 This region has been a favorite breeding ground for many years, and 
 much beef is constantly prepared for market, a large part of which is 
 accomplished by the use of prickly pear at some stage of its growth. 
 The great draAvback in any beef production — especially in the pro- 
 duction of baby beef — is a lack of continuity of feed. An abundance 
 of pasture is to be had in some seasons, but in other seasons it is too 
 short for the maintenance of a steady rapid growth. A roughage 
 like this, therefore, which can be utilized at any season and is a sure 
 crop, fills a gap not filled by any other. 
 
 Prickly pear roughage is relished by nearly all kinds of live stock. 
 No case is known of horses being fed on it, but other classes of .stock 
 eat it readily. Cattle, sheep, goats, and swine relish it, and even 
 chickens utilize it Avhen it is chopped for them. Hogs Avill eat even 
 stumps and heavy joints that cattle leave. 
 
 In short, it can be said that prickly pear is of vastly more impor- 
 tance in southern Texas than is ordinarily appreciated. A crop 
 which will produce twenty-odd tons of roughage to the acre per an- 
 num with a degree of certainty not attained by any other, and this 
 readily eaten by all classes of live stock, is not to be disregarded as 
 an important farui crop even if it has been looked upon as some- 
 thing of a nuisance in the past. 
 
 PRICKLY PEAR COMPARED WITH SORGHUM. 
 
 Upon another page it has been shown that 22f tons of prickly pear 
 can be grown each year upon the grav^lly-black-waxy soils of the 
 San Antonio region of Texas. Thfe main hay crop upon the ranch 
 where the experiments are conducted has always been sorghum, and 
 since the experiments were started this has been placed in a silo. In 
 the season of 1906 about 1 ton of silage was secured to the acre, and 
 in 1907 about 2^ tons. These are estimates made in the silo. 
 
 In feeding tests upon the ranch in 1905 it was found that 6 pounds 
 of prickly pear produced the same results in feeding dairy cattle as 
 1 pound of dry sorghum hay." If 1 ton of hay is assumed to be 
 equivalent in feeding value to 3 tons of silage, then the hay produc- 
 tion froui sorghum has been on an average for the past two years 
 only seven-twelfths of a ton to the acre per annum. This seven- 
 twelfths of a ton of hay, assuming the relative value of sorghum hay 
 to prickly pear to be as 6 to 1, is equivalent to only 3^ tons of pear. 
 In other words, prickly pear has produced more than six times as 
 much roughage during the past two years as sorghum. Of course, 
 the A^eld of sorghum mentioned here is abnormally small, but sea- 
 sons occur every now and then in this region when crops are short, 
 
 " See Bulletin No. 91, Bureau of Animal Industry, 1906, p. 4. 
 124 
 
28 THE PKICKLY PEAK AS A FAEM CROP. 
 
 and while they may be assumed to be at the lowest point of produc- 
 tion during these two years it is against these years of shortage that 
 it is necessary to provide. 
 
 ENEMIES OF THE PRICKLY PEAR 
 
 There are many fungus and insect enemies of the prickly pear, 
 but only one insect and one fungus need be considered in this place 
 because the others have not thus far given cause for any appre- 
 hension. 
 
 The black-spot fungus {Perisporium wrightii) is first found as a 
 soft, brownish area, usually more or less circular, on any portion of 
 the joint. This soon becomes black and rotten, and later dries up when 
 the ascogenous bodies appear upon the epidermis. Often there may 
 be a dozen of these spots on a single joint, and these are approxi- 
 mately one-half to 1 inch in diameter usually and extend clear 
 through the joint. When but one or two occur the joint may re- 
 cover, the tissue healing up around the diseased portion, when the 
 dried diseased tissue falls out, leaving a notch or a clear circular 
 opening through the joint. When the diseased spots are numerous, 
 the plants are very much impoverished and the joints often drop off, 
 the healing in this case occurring at the union between them. 
 
 Fortunately this disease appears less prevalent upon plants under 
 cultivation. In February, 1905, when the first plantings were made, 
 one row, 208 feet long, was planted to very badly diseased pear in 
 order to study the behavior of the disease. There are at present 
 some diseased plants upon this row, and many of the cuttings failed 
 to grow, but the vast majority of the plants have overcome the dis- 
 ease quite perfectly. It is much more common on some varieties 
 than on others, and the badly diseased material which was planted 
 was discovered later to be of a different variety from that which it is 
 recommended should be planted in the vicinity San Antonio. The 
 typical form of Opuntia lindheimeri which is recommended is much 
 less subject to this disease than some of the other native forms. It 
 is a common disease in many species of prickly pear throughout the 
 pear region from Texas to the city of Mexico. 
 
 The only practical remedy is to feed the diseased plants and propa- 
 gate from healthy stock only. At the present time it looks as though 
 this method of handling would reduce the injury to a minimum. 
 The cultivated area referred to, except where diseased pear was 
 planted, is quite free from disease now. The stock was carefully 
 selected, however, and there appears to be no disease on either the 
 cultivated or uncultivated areas. 
 
 The red spider {Tetimnychus opuntiae), on the contrary, is more 
 serious upon cultivated than upon imcultivated land. These minute 
 
 124 
 
ENEMIES OF THE PRICKLY PEAR, 29 
 
 animals work around the areoles of spines and spicules first and 
 g^radually cover the entire surface of the joint. After the}^ have 
 worked on the pear, a yellowish or brownish dead callus forms over 
 the entire surface. This cracks in places and there is often a consid- 
 erable exudation of mucilage, which, although white at first, finally 
 turns black. The plants are very much disfigured by this mite, 
 but it can not be stated at present just how much real injury is done, 
 for no plants have been observed which have been killed b}'^ it. 
 
 It may be difficult for the uninitiated to recognize what the trouble 
 with the plants really is, but after seeing it or having it pointed out 
 it can not be overlooked, for the diseased condition is very character- 
 istic. It is not so easy to find the mites, however, because they are 
 very small and at times nearly, if not quite, absent. 
 
 Just what tlieir habits are during the season has not been worked 
 out. It is certain that they were abundant in March, 1907, and less 
 abundant in the autumn of the same year. 
 
 The Mexicans are very familiar with this diseased condition, but 
 so far as known have not interpreted the cause. Attention has been 
 called to it several times bj'^ Mexican ranchers, who deplored its 
 presence and expressed the opinion that it might in time entirely 
 destroy such forms as nopal amarillo, naranchado, chaveiio, and 
 certain forms of joconoxtle. AVhile these fears express extreme 
 views, there is no doubt that the red spider is a pest to be reckoned 
 with. However, in Mexico, as in the United States, the greatest 
 injury is done when plants are close together or growing intermin- 
 gled with other shrub])ery. This crowding together of the plants 
 is probabh' the cause of vthe large numbers of mites which developed 
 in our cultivated experimental area. 
 
 Experience is altogether too limited yet to permit much, if any- 
 thing, to be said with any certainty about this injurious insect. 
 A few observations, however, may be of interest. These, concisely 
 tabulated, are as follows: 
 
 (1) The disease occasioned by the red spider has long been known, 
 but its cause has only recently been determined. 
 
 (2) It has never been alarmingly abundant upon the uncultivated 
 pear in southern Texas. 
 
 (3) At the end of the second year a few red spiders appeared in 
 our plantation. 
 
 (4) During the third season these mites multiplied rapidly and did 
 considerable injury to the older plantings. 
 
 (5) All plants harvested in any manner whatsoever in the spring 
 of 1907 were uninjured by the red spider during the season, although 
 some of them were badly infested when harvested. 
 
 124 
 
30 THE PEICKLY PEAR AS A FARM CROP. 
 
 (6) No red sjDiders were found during the season on plantings 
 made in the spring of 1907. 
 
 (7) The red spider has been abundant upon thick phmtings only, 
 and no injury has been done any of the plants except the natives 
 thus far. 
 
 (8) Red spiders are injurious only part of the year. In 1007 they 
 were abundant in March. 
 
 (9) Heavy rain washes the red spiders "off and they do not appear 
 to regain possession for some time, but just how long has not been 
 determined. 
 
 (10) Prickly pear having red spiders on it is eaten as readil}^ by 
 live stock as that which is not affected. 
 
 The above observations indicate that the red spider can be kept in 
 check by feeding such areas as are affected as they appear. The fact 
 that the crowding together of the plants seems to increase the spread 
 of the red spiders and the injury done may influence the method of 
 planting. 
 
 Another malady which is of very common occurrence can probably 
 be discussed here as well as elsewhere, because it is connnonly looked 
 upon as a disease. This occurs some time in the spring of every 
 year at San Antonio. It is a condition in which the new joints of the 
 plant drop off wdien about half grown. The recovery from its effects 
 is very rapid, but of course the growth which drops off is lost. 
 
 To illustrate the extent of this malady, a single case in which a 
 quantitative estimate was made can be mentioned. About the mid- 
 dle of May, 1905. a large plant harvested during the winter of 1903-4 
 had just recovered from the effects of this malady. It had made a 
 splendid growth the previous season and had started vigorously 
 again when the joints began to drop off. At the time referred to 
 most of the fallen joints were completely' dried. Fifty-two of them 
 were lying at the base of the plant, while eleven more were par- 
 tially injured. In spite of this, the plant had completely recovered 
 and was then supporting, besides the eleven somewhat injured joints 
 still clinging to it, fifty-eight perfectly sound and normal ones. 
 AVhat proportion of the latter started after the falling of the first 
 crop of joints can not be stated, but probably nearly all of them. 
 This was a large, vigorous plant (second growth) from an old stump 
 harvested several times, and probably represents an extreme case, but 
 it is not uncommon for one-half to two-thirds of the first crop of 
 joints to be lost in this way at San Antonio. 
 
 The exact cause of this particular phenomenon has not been 
 demonstrated, but it appears to be due to neither fungous nor insect 
 enemy, but, on the contrary, to be purely climatic. Observations 
 seem to indicate that the falling of the joints takes place some time 
 
 124 
 
SUMMARY. 31 
 
 after a cold and usually a moist spell of weather which occurs when 
 the joints are about half grown and while they are thin and leathery, 
 before they have begun to swell out into the normal shape of the 
 mature joint. 
 
 In 1907 this malady was at its height about April 27. At this time 
 nearly all the season's growth on many species was destroyed, and 
 in some none remained. In others about half fell off, while a very 
 few varieties were uninjured. The native Opuntia Undheimeri was 
 not much affected; possibly one-eighth of its joints were injured, 
 but not more than this. All varieties recovered speedily, putting 
 out new joints in a short time. No injury was done to the previous 
 year's growth. 
 
 While often a large part of the growth of a month or so in the 
 spring is lost in this way. no apprehension is felt regarding the 
 matter in respect to the yield. In fact, the 3^ields which are re- 
 ported elsewhere in this paper have been produced each year in spite 
 
 of this malad}^ 
 
 SUMMARY. 
 
 These experiments in planting prickly pear as a farm crop have 
 been conducted in a region having a rainfall varying from 15^*'^ 
 inches to 40^ inches a year, the average for the past eighteen years 
 being 28f inches, but this rainfall is very unevenly distributed. 
 
 The absolute minimum temperature for the locality is 4° F., but 
 this is exceptionally low, having occurred but once in eighteen years. 
 During the ten years ended in 1903 there was only one year which 
 had seven days with a mininnun below 22° F., two years had none 
 lower than 22° F., while the others had from one to six days during 
 the year with a minimum temperature lower than 22° F. 
 
 The plants are most advantageously grown from single- joint cut- 
 tings, wdiich are easily prepared by cutting up all of a full-grown 
 jjlant into single joints with a spud or spade. 
 
 Plants should be established about 2 feet apart in 6-foot rows. 
 
 When the ground is moist and w^ell prepared, cuttings can be 
 distributed on the surface of the ground. When these conditions 
 are not met the cuttings should be placed in a furrow and par- 
 tially covered with another furrow. With care a sulky cultivator 
 can be used for covering the joints. 
 
 Planting may be done at any time of the year except during the 
 hottest and driest part of summer. 
 
 Cultivation shoidd be shallow and sufficiently frequent to keep 
 down Aveeds and prevent excessive baking of the soil. 
 
 Plants set in February can be harvested at any time of the year 
 after twenty to twenty-four months. 
 
32 THE PRICKLY PEAE AS A FARM CROP. 
 
 It is believed that it will be found advantageous in harvesting to 
 singe the standing plants and then cut them down to be grazed. 
 However, good results have been obtained without cutting. It is 
 possible to singe after cutting, but it is a little more difficult and will 
 probably be attended with more waste. 
 
 It will be advantageous in harvesting to leave a stump of two to 
 four joints rather than to harvest too closely. 
 
 Those forms which are most vigorous and most free from disease 
 should be selected for stock to plant. In the vicinity of San Antonio 
 this is the t}q:)ical form of Opuntia Jindheimeri. 
 
 The experimental plantation cost nearly $9 an acre, including all 
 expenses, beginning with the breaking of the raw prairie and ending 
 with the cuttings properly placed. With good labor and proper 
 management this expense, it is believed, could be reduced to $6 or $7 
 an acre. Even $9 per acre is low for a plantation that does not re- 
 quire renewing for fifteen or twenty years. 
 
 The spineless forms thus far grown (about twenty varieties) are 
 practically useless under present conditions in Texas except for breed- 
 ing purposes. 
 
 A conservative estimate of the annual production of prickly pear 
 under cultivation is 22* tons, or enough roughage for one bovine 
 animal for a year from each acre of ground. This is to be harvested 
 biennially. 
 
 Cattle, sheep, goats, swine, and even chickens will eat the crop 
 readily at any time of the year. 
 
 Eight times as much growth of prickly pear has been secured 
 under cultivation as was obtained without cultivation in ungrazed 
 pastures. 
 
 More than six times as much roughage (actual feeding value) has 
 been secured during the past two j^ears from prickly pear as from 
 sorghum. 
 
 One fungous and one insect enemy of prickly pear of some im- 
 portance are found, both of which may be controlled either by 
 selection of stock or by methods of harvesting, or by both combined. 
 
 The diseased condition known as dropping of joints is believed to 
 be purely climatical. This, while costing a month's growth in the 
 spring, is not looked upon with any apprehension. The yields given 
 in this paper have been secured in spite of this injury. 
 
 124 
 
PLATES. 
 
 124 
 
 33 
 
DESCRIPTION OF PLATES. 
 
 Plate I. — Prickly pear experiments. Fiji. 1. — Cultivated and uncultivated 
 prickly pear, showing relative si'owths. The first two'rows cultivated and 
 thejfirst two rows uncultixated were planted in the same way and at the 
 same time. The vegetation in the uncultivated area consists of native 
 grasses and the broom weed (Amphcacharis (Iracunculoidcs). Fig. 2. — 
 Covering the cuttings with a plow. Covered in this way they usually stand 
 at an angle of about 45 degrees. Fig. 3. — Cuttings distributed in the furrow 
 ready to be covered. When covered with a plow they stand at about the 
 angle shown, but if a sulky cultivator is used to cover them they can be 
 arranged nearly upright. In the distance will be seen piles of cuttin.j;s 
 ready to be distributed. Fig. 4.— Cuttings distributed on tiie surface of the 
 ground. These are not to be covered, but will grow readily in this position. 
 This method of planting is to be recommended when the ground is 
 thoroughly prepared and sufficiently moist. 
 
 Plate II. — Prickly pear experiments. Fig. 1. — Cattle grazing singed prickly 
 pear on the experimental plantation, March, 1!)07. Fig. 2. — Singeing 2-year- 
 old pear upon the experimental plantation in Mai'ch, 1007. Fig. 8. — Uncul- 
 tivated plantation 20 years old upon the Poor ranch, at San Antonio, Tex. 
 This plantation bars been repeatedly harvested but never cultivated. Fig. 
 4. — Cultivated prickly pear 2 years old upon the experimental plantation. 
 Comjmre the aiipearance of the plants with the same variety shown in 
 figure 3. 
 
 124 
 
 34 
 
Bui. 124, Bureau of Plant Industry, U. S. Dept. of Agriculture, 
 
 Plate I. 
 
 PRICKLY PEAR EXPERIMENTS. 
 
 Fig. 1.— Cultivated and Uncultivated Prickly Pear. Fig. 2.— Covering Cuttings 
 WITH A Plow. Fig. 3.— Cuttings Distributed in Furrow Ready to be Covered. 
 Fig. 4.— Cuttings Distributed on the Surface of the Ground, not to be Cov- 
 ered. 
 
Bui. 124, Bureau of Plant Industry, U. S. Dept. of Agriculture. 
 
 Plate II. 
 
 PRICKLY PEAR EXPERIMENTS. 
 
 Fig. 1.— Cattle Grazing Singed Prickly Pear. Fig. 2.— Singeing Prickly Pear. 
 Fig. 3-— Uncultivated Plantation Twenty Years Old. Fig. 4.— Cultivated 
 Prickly Pear Two Years Old. 
 
INDEX. 
 
 Page. 
 
 Areoles, relation to propagation 11,14 
 
 Beef, baby, use of priclvly pear in production 20 
 
 Breeding hardy spineless varieties, possibilities 18,21 
 
 Callus, cuttings 11 
 
 Cattle, daily and annual consumption of i)rickly peai', estimates 8,22,23,24 
 
 Chavefio, injury by red spiders 29 
 
 Chickens, feeding on prickly pear 27 
 
 Climate, prickly pear requirements 9-10 
 
 Cold, effect on prickly pear 10 
 
 Cost of planting 19-20,32 
 
 Cows, ration of prickly pear 8,22,23,24 
 
 Cultivation 15-10 
 
 effects compared with noncultivation 24-20 
 
 first attempt ^- 23 
 
 Cuttings, preparation and handling 10-12 
 
 Dairy pastures, availability of prickly pear 8 
 
 use and adaptation of prickly pear 20 
 
 Enemies of prickl.v pear 28-31 
 
 Experimental planting. 1907. methods employed, etc 11, 12, 
 
 13-14, 17, 18, J9, 20, 23-24 
 
 Feed yield to the acre of cultivated prickly pear, estimates 22-24 
 
 Fence requii'enients of spineless varieties 21 
 
 Flavor, prickly pear, relation to use by stock 20, 27 
 
 Freezing fatal to prickly pear, Texas '. 10 
 
 Fruit, time of production 10 
 
 Fungus, black-spot, description and remedy 28 
 
 Goats, feeding on prickly pear 7,27 
 
 Grass, effect on growth of prickly pear 25 
 
 Greenhouse propagation, decay of cuttings, etc 11 
 
 Harvesting, time and methods 10-18,32 
 
 Hedges, use of prickly pear 7 
 
 Hogs, feeding on prickly pear 27 
 
 s:mplements for cutting, handling, and planting prickly pear 11,13,31 
 
 Introduction to bulletin ■, 7-8 
 
 Joconoxtle. in.iury by red spiders ' 29 
 
 Joint-dropping disease, cause and effects 30-31,32 
 
 Labor, negro and Mexican 19 
 
 Mexico, method of planting prickly pear, etc 12 
 
 Mites, red spiders injurious to prickly pear 13.28-30 
 
 Naranchado, injury by red spiders 29 
 
 Nopal amarillo, injury by red spiders 29 
 
 124 35 
 
36 THE PRICKLY PEAR AS A FARM CROP. 
 
 I'ase. 
 Opuutia liudlieimeri, description, cbaracteristics, and rt'conmiendalions.^ 1!>, 
 
 23, 26, 28, 32 
 
 freedom from disease 28,31 
 
 spininess increased under cultivation 26 
 
 Pear, priclvly, climatic requirements S-10 
 
 cultivation ir>-16 
 
 and use, historical notes 7 
 
 first attempt 23 
 
 fungous and insect enemies 28-31 
 
 feed produced . 22-24 
 
 growth, rate . _ 16 
 
 propagation and harvesting methods 10-18 
 
 spineless species, advantages and disadvantages 20-22 
 
 spiny species, advantages 22 
 
 uses 26-27 
 
 yield and value, comparison with sorghum 27-28 
 
 under cultivation 22-26 
 
 young growth distasteful to animals 26 
 
 Perisporium wrightii, description and remedy 28 
 
 Plantation, renewal 15 
 
 Planting, cost 12-14, 31 
 
 methods 12-14,31 
 
 season 14-15 
 
 Plants, selection for propagation 12 
 
 setting, distance apart 13,31 
 
 Plates, description 34 
 
 Poor. D. M., planting of prickly pear 15 
 
 Precipitation, San Antonio, Tex., monthly totals, 1807-1006 S-0, 31 
 
 Prickly pear. See Pear, prickly. 
 
 Propagation, areole as a factor 11,14 
 
 distance between plants _^ 13,31 
 
 methods and implements 10-14, .31 
 
 suggestions for insuring growth of plants 14 
 
 varieties recommended 18 
 
 Rabbits injurious, especially to spineless varieties 21 
 
 Rainfall, San Antonio, Tex., monthly totals, 1807-1006__ 8-0,31 
 
 Ration, daily, prickly pear for cattle 8,22,23,24 
 
 Red spiders injurious to prickly pear 13, 28-30 
 
 Rodents injurious, especially to spineless varieties 21 
 
 Roughage, value of drought-resistant crop 8 
 
 San Antonio, Tex., climatic conditions : 8-10,31 
 
 pastures, depletion of prickly pear 8 
 
 Season for planting 14,31 
 
 Setting plants in field, two methods 12-14,31 
 
 Sheep, feeding on prickly pear 7.27 
 
 Singeing process, directions 16-18,32 
 
 Sorghum, yield compared with prickly pear — 27 
 
 Spacing plants, proper distance 13,31 
 
 Spiders, red, injurious - 13,28-30 
 
 Spineless varieties, advantages and disadvantages 20-22 
 
 hardy, breeding possibilities 18,21 
 
 importations, experimental planting 20 
 
 not hardy, useless in Texas 20, 32 
 
 124 
 
INDEX. 37 
 
 Page. 
 
 Spines, development, effect of cultivation 26 
 
 liiiidrance to propagation of plant 14 
 
 Spiny varieties, advantages and disadvantages 20-22 
 
 Summary of bulletin 31-32 
 
 Swine, feeding on prickly pear 27 
 
 Temperature, average, San Antonio, Tex., 1888-1906 9-10, 31 
 
 Tetranychus opuntiae. injuries, observations 28-30 
 
 Texas, climatic conditions 8-10 
 
 forage cultivation, space between plants 13 
 
 land sales and holdings 7-8 
 
 need of drought-resistant crop for roughage S 
 
 varieties preferred 19 
 
 Varieties, care in selection 18-32 
 
 preferred forms 19 
 
 Yield to the acre under cultivation, estimates 16^ 22-24 
 
 124 
 
 o 
 
%. 
 
 LEJe'08