Texas Tech University Research Center Pantex, Texas

TEXAS TECH UNIVERSITY RESEARCH CENTER PANTEX, TEXAS

SPECIAL REPORT NUMBER 3 1

INTERNAT I ONA L CENTER for ARID ond SEMI - ARID LAND S TUD I ES

Research Center Reports 1970

TEXAS TECH UNIVERSITY RESEARCH CENTER PANTEX, TEXAS

DR. GROVER E. MURRAY \.President

DR. GLENN E. BARNETT Executive Vice President

DR. S. M. KENNEDY MR. G. C. GARDNER Vice President for Vice President for Academic Affairs Financial Affairs

DR. GERALD W. THOMAS Dean of Agricultural Sciences and Director of Research Center

DR. R. HOLLIS KLETT Superintendent

March, 1969 ~ March 1970 ACKNOWLEDGMENTS Grateful appreciation is extended to the following companies for the contribution of products and other assistance toward the research program at Texas Tech University Research Center in 1969-1970. Allied Chemical, New York, New York Amarillo Globe-News, Amarillo, Texas Amchem Chemical Company, Ambler, Pennsylvania American Breeders Service, DeForest, Wisconsin American Cyanamid, Princeton, New Jersey American Hoechst, North Hollywood, California BASF, New York, New York · Chas Pfizer and Co., Inc ., Terre Haute, Indiana Chipman Division of Rodia Inc., New Brunswick, New Jersey CIBA Corporation, Summitt, New Jersey Diamond Shamrock Company, Amarillo, Texas Dow Chemical Company, Midland, Michigan E.I. duPont de Nemours and Company, Wilmington, Delaware Franklin Parts and Supply, Panhandle, Texas Funk Brothers Seed Company, Lubbock, Te xas Geigy Chemical Corporation, Ardsley , New York Glover Packing Company, Amarillo, Texas H. J. Hughe s Grain Company, Panhandle, Texas Hercules Inc . , Wilmington, Delaware Hess and Clark Company, Ashland, Ohio Hooker Chemical Company, Niagara Falls, New York Humble Oil and Refining Company, Houston, Texas International Commodities Corp., Amarillo, Texas K.M.P. Lake Pumps, Earth, Texas Monsanto Company, St. Louis, Missouri Northrup-King Seed Company, Richardson, Texas Panhandle Tractor and Equipment, Amarillo, Texas Pennwalt Chemical Company, Bryan, Texas Reliance Chemical Corp. , Houston, Te xas S & S Mfg. Company, Claude, Te xas Shel 1 Chemical Company, New Yor k, New York Southwe st Pellets Corp., Cordell, Oklahoma St.amps Sprayi ng Service, Panhandle, Texas Stauffer Chemical Company, New York, New York Tayl or - Evans Farm Stores, Amarillo, Texas The Hamby Company, Plainview, Texas Tide Chemical Company, Edinb urg , Texas Tr i-State Equipment Company, Canyon, Texas UpJ ohn Chemical Company, Ka l amazoo, Michigan Velsicol Chemical Corporation, Chicago, Illinoi s Warn er Seed Company, Hereford, Texas Weeks and Bagwell Grain Company , Claude, Texas

PHOTOGRAPHS On the front cover is the Killgore Beef Ca ttle Center which serves as headquarters for r elated agricultural research. The back cover shows (1) several calves from t he study "Use of Crossbreeding in Commercial Beef Production"; (2) cattle feeding investigations have contributed greatl y to the development of the research program at Texa s Tech Research Farm; (3) agronomy research of forage sorgh um varieties; (4) fo urteen varieties of coo l season grasses are being studied in this nursery by Range Management personnel for possible irrigated pasture use. T A B L E 0 F C 0 N T E N T S

1969 FIELD DAY PRESENTATIONS Value of Gain to Cattle Feeders Jack Carrouthers . Crossbreeding as a Market for Purebred Cattle T. C. Cartwright . .. . 4 Weight Vs . Shape J . T. Elings . 11 Carcass Cut-out and its Value Da 1 e W. Zinn . 16 ANIMAL SCIENCE Nutritive Value of Waxy Sorghum Grain Reconsti tuted With Different Moisture Levels L. G. Finley and L. B. Sherrod ...... 23

Continuing Report on Project Entit l~d "A Compar ison of Beef Cattle Selected by Four Different Criteria" K. R. Hansen , R.H . Klett and D. W. Zinn. 27

Effect of ~wo Feeding Regime s Upon Performance of Early Weaned Crossbred Bulls and Heifers K. R. Hansen ...... 29 The Use of Crossbreeding in Commercial Beef Production K. R. Hansen ...... 31 Evaluation of Added Bacteri al Enzymes Plus Ba cteria Upon Utilization of Ground Reconsti tuted Sorg hum Grain by Finishing Beef Cattle K. R. Hansen and L. B. Sherrod .... 34 Mel engestrol Acetate and Chlortetracycline, Alone or in Com bination for Fi nishing He ifers K. R. Han sen, L. B. Sherrod and R. D. Furr . 37 AGRONOMY Influence of Pho sp horus Fertilization Levels Upon Yields and on the Availability of Iron and Zinc With Irrigated Grain Sorgh um Dale Hollingsworth, J. L. Green and William F. Bennett ...... 40 Yield and Chemical Compo s ition of Irrigated Sorghum Grains Produced With Different Nitrogen Fertilization Level s L. B. Sherrod and R. D. Furr . ... . 42 Sewage Effluent as an Irrigation Resource L. B. Sherrod, Dal e Hollingsworth and R. D. Furr ...... 46 (Table of Contents - continued) Control of Field Bindweed and Bur Ragweed with Soil Sterilants Dwane E. Lavake, Dale Hollingsworth, A. F. Wiese, Wayne Chenault and Wendell Vandiver ... •. .. •. 50 Weed Control Studies in Sorghum Wayne Chenault, Dale Hollingsworth, A. F. Wie se, Dwane Lavake and Wendell Vandiver 53 RANGE SCIENCE A Technique Study of Seeding Abandoned Cropland to Range Grasses Dale Hollingsworth and J . L. Schuster 59 The Effects of Burning and Fertilization on Production and Utilization of Weeping Lovegrass W. Ellis Klett, Dale Hollingsworth and J. L. Schuster ...... 61 Adaptation and Yields of Several Cool Season Grasses J. L. Schuster and Ricardo deLeon 64 Herbage Yields and Utilization of Playa Lakes on the Texas Tech University Research Center J. L. Schuster and Ricardo C. deLeon .. 68 ENTOMOLOGY

Additional Observations on the Control of ~ites Attacking Grain Sorghum Charles R. Ward, Ellis W. Huddleston, John C. Owe ns and Donald Ashdown . . . . • ... 71 VALUE OF GAIN TO CATTLE FEEDERS Jack Carrouthers* When I first came to this country in '62, feeding was not a big industry like it is now. It was just getting its start. At that time there were two or three people in this area that had enough foresight to see the future of it, and Dean Stangel was one of the foremost. What I am going to say on the value of "gain" to cattle feeders I endorse myself, but I certainly can' t put anyone else behind me on this. Let's talk about "daily gain . " As I speak you will have to remember that I am speaking from a practical standpoint, because I am a feedyard operator. Daily gain to us is one of the most important things that we figure . We run a commercial feedyard and one of the first things our customers want to know is what does it cost to put a pound of gain on. So, we look at this real closely. We do everything we can to put this cost down within a reasonable range. It is competitive. One feedyard seems to be competitive with another to see which one can do the job the cheapest. So let me speak for a minute of the facts that are going to affect us in thi s goal of putting on a cheap cost of gain. Some of these factors the feedyard itself does not actually have any control over. The person who buys the cattle and sends them in to us, has control over such a thing as the condition of the cattle when you weigh them and the kind of cattle that they are . Some cattle won't gain as cheap as other cattle. We know this. We try to buy higher costing gain ca ttle at cheaper price. If this is done, and if there is a profit, we can make as much profit on a cheaper grade of cattle as we can on a higher priced cattle . So this realy i sn't a factor if you realize it. Another t hing i s the weather. This is the one element that we cannot control. It is the one element that I don ' t think too much con sideration can be given. It is real important. We come into Winter months, and we don't have severe Winters. In Colorado we had a lot colder weather and a lot more snow and a lot more mud. Down here we think we have a pretty fair Winter climate, and we really do. But even the mi ldest of Winters will affect our cost to gain. They affect them to a degree that yo u woul d hardly believe in some cases. It is the range in the temperatures I suspect, cattle adjusting to this, utilization of energy for main tenance. Another thing would be the feed. Of course we all understand this. A highly concentrated ration will offer more calories to the animal who will put on more gain per day, ma ybe at a higher cost . This may not be the cheapes t way to do it. This is something we are continuall y faced with, should we feed a cheaper feed with a lower gain and a cheaper feed cost. These are all factors. Another thing is the length of time on feed. Th e longer we feed an animal, the higher cost of gain. There is an optimum like Dr. Cartwright was talking about. Th e optimum may not be the size cattle we want. A fourteen-hundred pound animal is not much good to us down here. An eight-hundred animal is too small. So we feed for something in the range of the lightest of possible 950 pounds, and I'm talking about steers, to 1200 po un rls in some cases. We have to market these cattle so we aim at a *Stockholder and Man~ger of the Friona Feed Yards, President of the Texas Cattle Feeders Assoc., Board of Directors of West Te xas Water Institute. weight that is most in demand. Some packers wouldn't touch a 950 pound animal. Some packers won't touch a 1200 pound one. All packers will buy an animal that weighs 1050 pounds to 1100 pounds. So this is our optimum range. We have to feed toward this. To get to this point, it is going to take time. How much time is determined by the energy i n your feed, and the size of the cattle coming in, and t he ki nd of cattle they are. Another thing is the size of the cattle as they come in. Smaller cattle we have found, will feed l onger at a comparable co s t of gain to a larger anima l fed less time. If we take a 550 pound steer cattle, we can feed him 180 to 190 days and come out with a cheaper cost of gain, than· if we had fed a 650 pound animal for only 140 days. Now this happens time and again, and I don't think I will have much argu ment here. The trend now i s possible toward feeding lighter cattle. At the present time it is pretty hard to get hold of heavy cattle there is such a demand for feeder cattle that the light ones seem to be all that is left. But this is not because they are bad. The last thing would be the kind of cattle they are . If we take a hard boned Hol s tein Steer that weighs 800 pounds, you are going to have a high cost of gain . If you take a good cross-bred animal that weighs 550 to 600 pounds, you will · have a cheap cost of gain. Thi s is al ong the· l ines of some of Dr. Cartwrights' thoughts . We get the advantage of growth. Growth is a real important factor. A hard bones animal you don't have any growth left in him, it is comparable to fe~ding a cow, and you do not get a cheap cost of gain on cows. All of these factors that I have mentioned : condi tion of cattle, weather, feed , hea lth i s another thing, length of time on feed , size of cattle, kind of cattle, we can control, myself as a f eedlot operator and you as a purchaser of cattle, we can control all of these but the weather. In this particular area, overall, our weather i s better than any other in the Unit~d States, bar none. Winter weather in Phoenix is better than here, but their summer weather is too hot. So we are sitting here in the f i nest cattle feeding area possibly in the world. The elemental part of this, we can f i gure the cost per pound to gain very si mply by taking our total feed costs plus our veterinary costs and dividin9 it by the number of pounds of . gain. This will come up with a figure anywhere from 19¢ to 23¢.

Another t hing that i s even more impo~tant to me, the f i gure that really tells wh ether yo u are doing a good job or not , is your conversion figure. Here is a figure that would certainly be re lated to heridity, cross-breeding. Ano ther simple way to figure cos t of gain i s to correlate figures for t he t wo t hi ng s so tha t you can und erstand them. It is the co s t per pound of feed ing, in other word s i f we have a ration that cos ts $50, the cost per po und of feed i s .025¢. You put yo ur veteri nJry expenses on top of tha t it will c hange it , but thi s i s cost per pound of feed times the conversion, eq ual s your cost to gain . This i s rea lly s i mple, but it illus trates t he importance of this co nv ersion business. I f you can drop yo ur conv ersion one point , yo u cost of gain decrease i s monum ental. So here again we are looki ng at he rid i t y . And we are look ing at the kind of catt le and the efficiency these cattle have. The ne xt thing I woul d like to s peak about is breeds . am not going to point out any pa rtic ul ar breeds, just the impor t ance of breeds. From my practical experience, all breeds react differently in the feed yards. All breeds have the i r good po ints , and all breeds have their bad points . We have som e that marble l a te, after they put on t oo much rind. We have some that mature fast and be come inefficient when you t ry to hold t hem for wei ght. We ha ve some that are too growthy. So, the thing here is to pick out the good points of your breeds, and combi ne your breeds to give us an anima l that is i dea l in the feed yard. One t ha t has

2 the growth, one that has the abil ity to marble, one that has the ability not to rind up, and one that has the ability to give you the confirmation you need to reach a choice grade. So, ba sically, what we need is a fast gain, low conversion, the ability to marble to choice, a big rib-eye, no rind , and good confirmation. This brings me to the last part, and one that is really dear to my heart, the housewife. I heard a remark, and I don't agree with it, but it was that we should make the housewife eat what we want her to eat. I think we should produce what the housewife wants. We can take an animal in the feedyards today and when we sell him to a packer, the packer is able to offer us a price for these cattle by what he thinks they will grade an d by what he thinks the cattle will yield. You take your dressed price, which is 45 1/2¢ today, and multiply it by yield and this gives you the price he is going to bid you on the cattle, percentaged out to how many will grade choice and how many will grade good. Here i s an area that I personally think needs a l ot of work. In other words he wants a high yielding average and in too many cases this high yield is brought about by excessive rind. Something that is a waste. Before the housew i fe ever gets this rindy steak on her table, maybe an inch of fat has been cut off the outside of it. If the packer is doing his own fabricating, he cuts th is fat off and throws it in the tank. Gets 5¢ per pound for it. So, the industry today is far from perfect, it is far from ideal. It won't be ideal until we can prod uce just what the housewife wants with no waste. This can be done, I feel· sure it can. By so doing, we are going t o aide our business tremendously. What I am talking about gentlemen, is reach ing a choice grade in as few days as possible. I think right now we can do it in 100 to 120 days, with a minimum amount of rind so the housewife is getting the choice beef she wants with no waste. You can imagi~e what this will do to our industry. At the present time and in the past we have always been confronted with an over supply. Excessive ton nage, when you get this excessive tonnage, the market goes down, and as long as there are cattle there are going to be optimists, and if you have a good market one year, you can rest assured you will have good supply the next year. Now, if we can get the packers, and the retailers, to give us a premium price for these selected cattle, which they cal l yield grades, then we can afford to do this, but today we can't, because we have got to feed for yield and to feed for yield you are putting on weight. This housewife is a tremendous co nsumer, and we need her real badly, and I think that the whole industry has got to work toward giving her what she wants at a price she wants to pay for it. Along this line I would like to get in a little plug r ight now. The Texas Cattle Feeders Assoc. has just started a beef promotion in Texas. We are aiming at the Housewife. We want her to try Texas Grainfed Beef. It is the best product there is. Our Milo fed beef is as good as any corn fed beef ever produced. So, we feel it is worth our while to spend money on this.

3 CROSSBREEDING AS A MARKET FOR PUREBRED CATTLE T. C. Cartwright* Hybrid cattle will continue to increase and will have an impact on the Texas econo my comparable to hybrid sorghum . This development is important to purebred breeders since hybridizing cattle requires large reserves of purebreeds . The significance of purebred cattle takes on a new dimension in creating hybrid vigor. Our research results on ·hybrid vigor in beef cattle led me to predict 15 years ago that we would have a steady i ncrease in crossbreeding designed to create hybrid vigor. Indeed we have seen a steady increase in Texa s during the past decade and now the Mid-West is following our example in research and in practice. We said that the main determent to crossbreeding was prejudice and market discrimination, but that these would dwindle and they have dwindled. I believe we are now poised for a mega-s tep toward utiliza tion of both hybrid vigor and performance testing in beef production. To coin a term, I '11 call it the application of economic genetics, i.e., the combination of production economics theory with beef cattle genetics. There are still important questions to answer with research but our knowledge has matured to the point of asking ourselves the right questions. Even though we haven't worked out all the technical bugs in designing a system to get maximal return, we can get much c loser than we could even two or three years ago. Let's consider some basic facts which dictate an efficient crossbreeding design 1. The inputs into a production operation are con ditioned more by the characteristics of the breed ing herd than by the sa le calf. You can see from table 1 that, on average, almost two cattle are required in the herd to produce one slaughter steer or heifer. The producer logically must place more emphasis on the feed efficiency of the breeding herd than on the f eed efficiency of the calf. Table 1. Compos i£ion of a beef herd producing 100 sale calves a year.

Brood co ws 150 Replacement heifers, yearlings 20 Bulls, purchased 6 196 Keeper calves 20 Sale ca lves 100 Tctal 296

aAssuming: 80% net calf crop per year 13% cow replacement per year 4% purchased bull s , 25% replaced per year

*Professor of Animal Genetics, Texas A&M University 4 2. Maintenance requirements are approximately proportional to body weight to the 3/4 th power . For example, a 1200 lb . cow is 1/2 again heavier than an 800 lb. cow and about 1/3 again more feed, or range, is required for her maintenance. 3. Genetic potential for rate of gain tends to i ncrease as genetic potential for mature size increases. The correlation is generally high though not perfect. There are several important implications that a com parison of the two different growth curves in figure 1 illustrate. The bull growing to a larger mature weight grows faster and longer but reaches puberty and al 1 other stages of maturity at older ages . Steers and heifers from the large bull . would be expected to weigh more and have less finish at either 1000 lb. weight or at one year of age for example. 4. Slaughter we ight which is optimum for obtaining greatest beef production for nutrient input tends to increase as rate of gain increases, as cattle price increases, or as f eed cost decreases. Compare different type cattle only when the calves are taken to their best weight. For example, a steer with a weight potentia l for gaining 2.0 lb./day at 10 months of age should be s laughtered rough l y at 800 lb. at todays prices while one with a gain potential of 2. 5 lb. /day reaches optimum slaughter weight at 900 lb., 2.7 lb. /day at 1000 lb . , 3.0 lb. /day at 1100 + and 3. 5 lb./day at about 1350 lb. See table 2 for more detail. In a recent s tudy we found the optimum slaughter weights of steers of different breeds; for example H, 3/4 Hereford - 1/4 Brahman, and Santa Gertrudis had optimum weights of 1040 lb., 1155 lb., and 1240 lb., respec tively . Weaning weights, ADG or yearling weight of dif ferent breeds sho uld not be compared to one another. They should be compared on the basis of cost of produc ing a pound of beef when the cattle to be s laughtered are taken to their best weights. Slaughtering cattle at about 750 lb . when their optimum is 1000 lb., loses efficiency about like a 10% reduction in calf crop. Table 2. Optimum Slaughter Weights For Beef Cattle

Ratio of Price Per Pound Steer/Price Per Pound Feed ADG 6 8 10 1 2 14 1. 8 510 585 640 680 700 2.0 560 660 715 770 790 2. 2 605 71 5 7g5 855 890 2.4 650 790 880 935 985 2. 6 690 850 955 l 02 5 1075 2.8 73 0 905 1035 1110 1170 3. 0 780 980 11 10 1210 1280 3.2 810 1025 1195 1300 l 375 3.4 865 1095 1270 13 95 1485 3. 6 890 11 50 1355 1495 1590

5 2000 Bull l 1900 lb.

1600 Bull 2 lSOO lb,

:9 1200 .; ....&:eo ~ 800

Age (Months from Birth) Figure 1 . Weight-age curves depicting the genetic potential of two bulls - one a "small" type and the other a larger type. The table below refers to these growth curves . Bull Weight 8ain Yearling no. Birth to 7 mo. 1 mo . to 15 mo. weight

1 440 1 b. 3 00 1 b. l 000 lb. 2 3 00 lb. 23 0 1 b. 660 lb . 5. F hybrid cattle tend to out perform their parent breeds . Glnerally the greater the genetic difference between the breeds, the greater the hybrid response. Consequently, when F 's are bred to F 's the offspring lose hybrid vigor. 1 Al so, when F1 's 1 are mated back to one of the original breeds the hybrid vigor in the offspring is de creased. Hybrid vigor and heritability vary for differ ent traits such that for any one trait if one is high the other tends to be low. Gainability and carcass and meat traits tend to be high i n he ritability. Ability to thrive and reproduce tend to be high in hybrid vigor. F1 hybrids tend to have less "breakdowns" or "down time" especially under stress. This includes the stress of shifting f rom a pasture or range environment to a feed lot. Table 3 emphasizes the logic of selecting to improve performance for traits low in heritability.

6 Table 3. Approximate Categories of Heritability and Hybrid Vi gor

Trait Heritability Hybrid Vigor Categories Leve l Level Tenderness, ribeye area Specific conformation points High, Low, I. Mature weight 50%+ 5%- Butterfat % Rate of gain in feedlot Milking ability Medi um Medium I I. Birth weight Weaning weight 20 to 50% 5 to 1 0% Overall conformation

Mothering ability Low, High, I I I. Calving interval Conception rate 20% - 10%+

The important desirable traits to consider in selecting cat tle for efficient beef production that extend logically from the basic points above are: 1. Consistent, high fertility B, C 2. Smal l size and low feed or land cost per cow c 3 . Early puberty and ability to calve easily c 4. Good milking qualities c 5. Adapted to thrive in area c 6. Sound, docile and l ong lived c 7. High ADG and efficient feed conversion s B. Lean, muscular carcass with high cut out s 9. Tender, palatable beef s Obviously some of the desirable traits are antagonistic or conflict one with another to a high degree in some cases. However, cattle in the beef producing system can be c lassi f ied according to function as either bulls, brood cows (including re placement heifers), or steers (including slaughter heifers). The traits of prime importance for each, disregarding genetic aspects, are: Bulls: 1 Brood cows: l, 2, 3, 4, 5, and 6 Steers: 7, 8, and 9 There is very l i ttle overlap in this classification, but the antagonism remains when the sires and dams necessary to produce t he steers are considered if we limit our thinking to a straight bred operation. In this case a general purpose , middle of the road approach is best. If straightbred cattl e are taken only to weaning and are then sold, smaller cattle are more efficient, but if they are owned by the producer through the feedlot, larger cattle are more efficient. However, since different breeds have different characteris tics which tend to be highly heritable on a breed basis (selec ting breeds vs . selecting i ndivi duals within a breed), cross breeding s uggests a resolution of the conflict and offers a bo nu s of hybrid vigor. The appropriate choice of breeds for crossbreeding and the 7 system or way they are put in the cross to complement each other is the key . Since breeds which are s elected because they tend to be maximum for some desired trait {such as high ADG and efficient gain) will have some undesirable traits {such as l arge mature cow size and high maintenance costs), different breeds must be se lected for different purposes. Choose a breed to fit in the breeding plan so that its strong or desirable traits are utilized, but also so that its wea k or undesirable traits are avoided. Let's consider one system which puts breeds together in such a way as to ma xi mize beef production per unit of land or per unit of investment. Select for complementarity of the breeds and for performance of the individuals. First, breed or purchase F crossbred heifers for brood cows . Smaller breeds that reach puberty early, are highly ferti le and adapted to the area are preferred. It is important to have the hybrid vigor boost in the cow. She needs it most to stay out on the range and conceive, deliver and nurse her calf well . Second, breed these F cows to a bull of a third breed. Bulls selected both indivi~ually and by breed for gainability and meatiness are indicated. These bulls should be purebred to get an extra hybrid kick in the calf and because selection is more effec tive in purebreds. The breeding value of individual crossbreds is less predictable than of purebreds. Third , own all calves until they reach optimal slaughter weights - then sell them all. Angus-Jersey cows bred to Charolai s bulls illustrate this system for Central Texas. At the Te xa s A&M University Research Center at McGregor, Jersey-Angus cows averaged 649 lb. while their calves weighed 479 lb. at 210 days and 681 lb. at 10 months. This system, of course, requires that three pure breeds be maintained - two to make the F1 heifers and one for the sire. There can be little doubt that systematic crossbreeding properly designed is the most efficient method of producing beef. A producer should not start crossbreeding without a sound apprai sal. There are a number of practical considerations which favor utilizing his present cow herd for any system he chooses even if he decides on a rather sharp change in his system. He must ask himself specifically what his resources are be st s uited to pro duce and market; weanling calves, stockers, feeders, F heifer replacements or slaughter steers. Then he should design1 his breeding prog ram specifically for that purpose . Also there can be little doubt as t o the opportunities for purebred breeders in the future. Purebred of "purity" of breedinq loses significance where performance of the individual is the criter ion. "Purity" of breeding takes on new significance in crossbreeding si nce creating hybrid vigor is the major objective and the degree of vigor achieved is related to the distinctiveness and purity of the breeds crossed. Furthermore, purebred breeds or herds specialized for com bining ability will be in demand. Rathe r than selection for purebred performance, these cattle will be selected on the basis of the performance of their crossbred progeny . Breeds will advertise their ability to nick with other breeds . Some breeds are better suited as female lines . Others are !Letter suited as sire lines. The female line selection should 8 !11 be based on the traits a cow should have. A sire line should iave traits desi red in slaughter steers - gain-ability and carcass ~ua lity - and so sel ected. Sti ll further, there is al ready a strong market for F heifers - they do bring a premium. (We often hear about 1 prem iums but seldom actually see them. These are real.) It takes purebreds to produce F1 's. It takes purebreds to supply replacements for herds that produce F1 ' s. Tab le 4 shows that for every 1000 F1 cows in the type program described earlier, about 650 purebreds are required to back it up.

Table 4. The F1 heifer producer is a new significant outlet for purebred heifers. The onsl aught of dairy breeds and now a who l e array of new breeds f rom cont inental Europe ( heralded by Si mment al) will put new pressure on the purebred breeder to be a better cattle -breeder. Crossbreeding has opened up a challenging new era for purebreds . That is, spec ia lization vs . generalization - best cattle for a s pe cific purpose vs. best cattle for a general purpose. The demands are greater and the oppo rtunities are greater. In fact, the future for pureb~eds is brighter than at any t i me I can recall. Shift the emphasis from "Breedi ng Better Cattle" to "Bet ter Cattle Breeding" . References

Joandet, G. E. and T. C. Ca rtwright. 1969. Relationship among breeding groups and efficiency of beef production . J. Animal Science 28: {in press). Franke, D. E. and T. C. Cartwright. 1969. Estimating optimum sla ughter wei ght of steers of different genetic potential. Te xas Agric. Exp. Sta. P.R. Fi tzhugh , H. A., Jr. 1967. Relationships of growth and size in cattle. Texas A&M Un iv. Animal Science Dep t. Tech. Rpt. l 0. Cartwright, T. C. lg69. Future of beef cattle breeding. Ga. Coastal Plains Beef Cattle Short Course . Jan . 8, lg69.

9 Table 4, The purebred berda and nUlllbere of purebred• required to auetain an 8 r 1 8 x Third breed

250 Purebred i X 10 Purebred

17 Purebred ~ X 1 l'urebr9d ti Breed B Bread· I

340 Purebred i X 14 Purebred

50 Purebred i X 2 l'urebr.. ' Breed C lra.d C

1000 r 1 i X 40 Purebred

Total r1 Cove • 1000 Total Purebred Cova • 657

aAssumptions : 1. ) 13% replacement rate for Fi cows 2.) 15% replacement rate for purebred cows 3.) Four bulls per 100 cows with 25% replacement rate 4. ) 80% net calf crop for straightbreds 5.) 85% net calf crop for purebred cows dropping F1 calves 6.) 10% heifers culled 7.) 20% purebred heifers culled 8.) 50% purebred bulls cu ll ed 9. ) 50% cal ves heifers, 50 % bulls 10. ) Sire replacements for purebred herd come from each purebred herd WEIGHT VS SHAPE J. T. Elings* The art of animal breeding is older than recorded history. :or centuries early day cattlemen, animal breeders, unconsciously Jsed genetics in developing the "ideal" animal. Varra, probably )ne of the first animal scientists, is credited with writing what follows, in Rome in the first century after Christ: "In buying :attle, see that they are well set up, clean limbed, square bodied, large, with black horns and broad brows, large black eyes, hairy !ars, s nub-nosed - a neck muscular with long dewlaps hanging from It, the barrell large and well ribbed - a tail sweeping the heels, tnd the end being frizzled with a heavy brush. In addition you ;hould be particular that the bull is of good breed, which is ~ete rm ined from his conformation and tis get, as ca lves usually reproduce the qualities of their sire." So spake Varra, in the first century . ' Then there was Robert Bakewell, who 1 i ved in the l Bth century ~n England, a man way ahead of his time. He measured and selected ~or meat producing ability in his longhorn cattle and paid little attention to fancy points. Bakewell studied the important economic ~haracteristics such as the proportion of the weight that was salable as meat.; meat quality; efficiency of beef production. He bred animals that would "weigh heavily in the best joints," and showed efficient feed conversion and quick maturity . He mated the best to the best, regardless of bloodlines. Robert Bakewell - probably the first man to evaluate performance. Then came the livestock shows and they played an important role in shaping cattle and establishing fads and fancies. Then about thirty years ago , production testing and /or performance eva luation got started. You have a fine monument, if I can use tha t term, to performance evaluation here in the Killgore Beef Cattle Center; and breeders like Emmett La Fore, Paul Dauer, Max Blau, and Cobie Conkwright, who put cattle in the first test 19 ~ears ago, and have some here today. They are pioneers in pro duction testing - progressive cattle breeders . I n recent years, along with the fa i rly universal acceptance of performance testing in beef cattle, there has been another con cern - that is, what i s under the hide? The emphasis is on more muscle, more lean, and less fat! Fat that is wasteful, that has ~to be trimmed; fat that is expensive to put on, and is the reason why the med ical profession severely li mits beef in some human diets because fat contains cholesterol. After li stening to Dr . Cartwright; then Mr. Jack McCarrothers; and finally Dr. Dale Zinn, I'm wondering whether I've got anything left to talk about. In fact my title, "Weight Vs Shape," corrals all the previous. talks. Locating beef bulls that will sire rapid-ga ining offspring, which produce carcasses yielding a high percent of closely trimmed

*J. T. Elings, Extension Animal Sci entist, University of California at Davis, as presented at the Annual Field Day P.rogram, Te xas Technological College Research Farm, Killgore Beef Cattle Center, Pantex, Texas, March 6, 1969 . ·

11 retail cuts, is a complex, difficult, and expensive assiqnment. Many procedures and methods have been used to evaluate the live anima l for these traits. Among these methods wou l d be visual appraisa l (conformation), probing, sonic wave devices, biopsy techniques, and others. Although some of these practices show promise , none of them are accurate enough to be relied upon in improved animal breeding work. In 1962, the University of California Agricultural Extens ion Service and the Department of Animal Science launched a program to progeny test beef bulls for growth rate and carcass merit. Two or more bulls of the same breed were each mated to 25 to 30 cows. These animals were managed on the same ranch under the same environment. During the breeding season, they were run separately; after breeding, all grazed together . All cows and bulls were weighed and graded at the beginning of the tests. Shortly after birth, calves were identified as to sire and dam and birth dates recorded. Their weaning and postweani ng performance was recorded as well as carcass data. To date, data on the progeny of 54 bulls have been accumulated. Of this total 14 are Angus bulls and 36 Herefords and four Shorthorn. A total of 550 calves representing the progeny of these 54 bul l s is included in this program. The fol lowing information has been secured on each calf: birth date, wean i ng weight, rate of gain in the feedlot, weight per day of age; carcass data include grade, rib eye area, carcass index, etc. The average final weight for these 550 calves was 948 lb., and their daily gain on test was 2.49 l b. In analyzing these data, it was found that fast-gaining anima l s produced carcasses that yielded just as high in adjusted retail cuts as did the slower-gaining cattle. Thi s would suggest that t here is no antagonism when selecting for growth rate and carcass merit. Table 1. Re sults of progeny test of 54 bulls, California.

Avg. No. Avg. Cold % Primal Cuts Steers Age Carcass Wt. W.D.A. Actual Adjusted* (days) ( l b . ) (lb. ) (%) (%) 284 438 597 +2. 06 49.82 50.20 266 495 548 -2 . 06 49.77 50.14 *Adjusted to Choice-minus grade. When the co ld carcass weight is multiplied by percent of primal cuts and thi s multiplied by 70¢ per pound, the f ast-gaining cattle re turned $17.28 more per carcass on actual cutability and $17.45 per carcass when adjusted to the Choice-minus grade . Plus- gaining steers (284 head) Adjusted Adjusted ... 597 lb. x 50.20 x . 70 $209. 79 $209. 79 + gainers Actual ..... 597 lb. x 49.82 x .70 $208. 20 - 192.34 gainers $ l 7. 4 5 Minus-gaining steers (242 head) Actual Adjusted ... 548 lb . x 50. 14 x .70 $192.34 $208.20 + gainers Actual ..... 548 lb. x 49.77 x .70 $190.92 -190.92 gainers $ 17.28

l 2 Summary , California Beef Cattle Progeny Testing Program 1964-1965. Adj . Va l ue Wean . Gain Final Care. ca re. retai 1 value A. D. G. care. U.S. va 1 ue index* cuts Herd $ 1 b. wt . Grade $ % $ A 1 145.28 2. 32 1. 28 c 202 . 28 51. 58 202 .78 2 15 2. 19 2.28 1. 30 c + 209 . 30 50.41 20 5. 16 B 1 142. 18 2. 14 G + 211. 37 49.88 194.45 2 134.09 2.33 c - 228.09 50 . 40 210.94 c 1 145.25 2.32 1. 30 c - 223.91 49 . 46 208. 84 2 148.06 2.44 1. 32 c - 231. 21 49.55 212.99 • D 1 143. 5 9 2. 01 1. 18 c - 211.g5 49.00 196.01 I 2 146.00 2.27 1. 27 c - 2 33. 18 48.35 206.86 E 1 110 .72 2.01 1. 11 G + 186. 21 4 9. 13 165.97 2 117.22 2.50 1. 27 G + 216.89 49.40 189. 33 F 1 11 0. 93 3.30 1. 21 c - 233.06 49.25 196 .22 2 111 .54 3.27 1. 21 c - 227 .71 49.05 194. 19 3 106.08 3. 33 1. 21 c - 23 1.46 50 . 16 197. 28 H 1 110 . 47 2. 45 1. 18 c 226.98 50. 12 204.09 2 120.04 2.63 1.28 c 248 . 87 49.79 222 . 45 J 1 120.68 1. 95 1. 26 c + 215 .70 51. 16 206. 13 2 118.03 1. 91 1. 20 c 209. 17 51. 34 197.78 n K 1 93.19 2. 31 1. 37 c - 207.36 50.07 201. 57 2 97.49 2.20 1. 26 c 202. 11 50.33 197.67 3 100. 71 2.28 1. 40 c 226. 91 49.82 219.60 L 1 117. 44 2. 69 1. 34 c - 267.36 51 . 10 233.12 2 105. 10 2.45 1. 17 c 234.31 49.96 198.07 N 1 107. 14 2.84 1. 19 c - 242.36 50.47 203. 04 2 108 . 20 2.82 1. 14 c - 234.02 50.89 198. 49 3 110 .26 2.79 1. 18 c - 248.03 51. 45 208.06 p 1 136. 47 2 . 27 1. 32 c - 216.44 50.47 193.36 2 139.95 2. 11 1. 31 c - 205.25 50.19 188. 50 *Adjusted to low Choice grade. Note: The higher gaining cattle as indicated by their feedlot gain in the A.D.G. column above have adjusted carcass indices as high or higher than the lower gaining progeny . A test was established i n 1964 to compare t he performance of Choice grade feeders and Okie cattle. A total of 125 high quality Hereford steers were purchased from Siskiyou County. Under the University of Ca lifornia grading system, these animals graded 88-plus . Another 125 Herefords were secured from Humboldt ~ounty , and their grades averaged 86-minus (stil l in the Choice grade) . The Okies were No. 2 ' s and graded in the low 80's and high 70 ' s. The Humboldt County cattle arrived i n Davis during September, the Siskiyou cattle in October, and the Okies in November. Eighty pe rcent of the Okies were bulls , and appro ximately 70 percent had horns . They were cas trated and dehorned before the beginning of the test. The investigators of this research program are of the op i nion that these operations were an extreme setback to this group of animals . One-half of each group was put on feed as calves in January and full fed until they reached a low Choice grade. The remaining half was grazed on the range for 215 days and then finished in the feedlot for a yearling phase study. However, because the Okie cat~le were small er tha n the others, one group of Okies was fed unt1l the animals reached the same weight as the He r efords . 13 During the calf stage of this experiment, the high-quality animals significantly outgained the Okie cattle (table 2). A live feeder grade was placed on each animal in all of these groups. The average grade for the Herefords was Choice, while the Okies graded Good. However, the conformation scores on the carcasses of these cattle were startling. During the entire feeding period, the Choice cattle did not improve in grade, while the Okie cattle went from Good to high Good and on to Choice . The f i nal carcass grades on the Hereford cattle were Choice; Okies fed for the same time were Good-plus. However, when the Okies were fed to the same weight as the Herefords, the off-breed cattle had the same final carcass grade (Choice). This, then, indicates that present standards of app ra ising live cattle are not in keeping with methods used in judging carcasses in the slaughterhouse without the hide, head, and legs. In this test, live grades were Choice and Good; carcass conformation grades all were Choice. The percentage of fat in the carcass was lower for Okie cattle than for the Herefords (table 2). The cutability (per centage of closely trimmed retail cuts in the round, rump, loin, rib, and chuck) of these cattle was in favor of the Okies, al though this was not significant. Table 2. UCO Hereford-Okie Experiment, 1964-1965. CALVES Herefords Oki es Siskiyou Humboldt Fed for Fed to County County same time same weigh! Number of steers 30 30 30 20 Days fed 1 91 191 191 244 Initial weight, pound (empty body) 425 435 383 376 Daily gain, pound 2.95 2.94 2.62 2. 51 Carcass weight, pound 633 639 559 633 Feeder grade, live Choice Choice Good Good Conformation score Choice Choice Good + Choice (2 Prime (1 Prime Carcass grade score 21 Choice 20 Choice 13 Choice 17 Choice (7 Good (9 Good (17 Go od ( 3 Good Yield grade 4.0 3.9 3.2 3. 1 Body fat, % 23.6 2 3. 1 21. 1 23. 1 Fat thickness, inches 0.60 0.56 0.41 0.52 Kidney fat, es ti- mated % 3 . 2 3.2 3. 2 Rib-eye area, sq. in. 10.5 10.8 10. 7 11. 5 Reta i 1 cuts, USDA, actual % 48.3 48.6 50 . 2 49.5

The original cost of the high-quality Herefords was $30/cwt; medium Herefords $29; and Okies $26.40. This is the feeder cost plus freight and death loss. This difference in price represents conformation and quality. The s elling price per 100 pounds of carcass weight was Siskiyou Herefords, $40. 16; Humboldt, $39.91; Oki es fed for same, $39.90; and Okies fed to same weight, $40.48. This again shows that, although live conformation scores of Okie cattle were far below that of Herefords, they sold for j ust as much money on the hooks as did the others.

14 When th~ performance was based on empty body weight, high qual i ty Hereford cattle returned $6.72 per head more than Okies fed for the same time . Herefords returned about 18 cents per head more than Okies fed to the same weight. This profit was due to rate of gain, because carcass prices were s imilar. But when the actual purchase weight is considered, high quality Herefords returned $3.92 per head more than Okies fed for the same time. However, Okies fed to the same weight return ed $2.31 per head more than the Herefords. Another thought- provoking experiment wa s conducted by the Department of Veteri2ary Anatomy, University of Queensland, Brisbane, Australia. Herefords and Angus, 3/4 Brahman X 1/4 Hereford, 1/2 Brahman X 1/2 Hereford, and unimproved Northern ·Territory Shorthorn cattle were studied for percentage of muscle-weight distribution in the carcasses. The precentage of expensive muscles (similar to our primal cuts, such as round, rump, rib, loin and chuck) was almost the same in all of these breeds. This percentage of muscle-weight distribution was not arrived at by the dual grading formula, but by actual dissec ting the muscles from bone and fat (table 3). Table 3. Percent Muscle-Weight Distribution (Brisbane, Australia)

Unim- Polled 3/4 1/2 proved Here- Here - Brah- Brah- Short- ford ford Angus man man horn

Number of animals 19 8 5 5 9 8 Standard muscle groups Prox. hind 32.21 32.61 32. 15 33.07 33. 76 32. 15 Spinal 12. 18 11 . 94 12 . 20 11 . 7 6 12 .07 l 2. 30 Prox . fore 11 . 5 2 11. 04 11. 25 11. 55 11. 01 11. 66 Expensive muscles 5 5. 92 55.59 55.61 56.38 56 . 84 56 . 11

The researcher, R. M. Butterfield, an anatomist and trained meats authority, suggests that selection methods used over the past 200 years in beef cattle breeding may have on l y changed the shape of muscles and added fat to it. The percentage of muscle weight in the ex pensive muscles of t he carcasses has not been altered. Therefore, he advises that, since this percentage has not changed, we s hould place more attention on growth rate in cattle. In conclusion, I hope that I have put across and re-emphasize the importance, the economic importance, of rate of gain. I have show~ that fast gaining cattle of the same age and grade, cut out as high or higher in primal cuts as slower gaining cattl e. Re search work by Bogart in Oregon and Gregory in Nebraska substan tiate these results.

In other wo r ds, my title should not be WeiQht ~ ~· It sho uld be Rate of Gain and Carcass Merit are Compatible. Reference Material was developed from University of Ca l ifornia Agri cultural Extension Service publication AXT 222 authored by Re uben Albaugh, Extension Animal Husbandman, Emeritus.

l 5 CARCASS CUT-OUT ANO ITS VALUE Dale W. Zinn* Never in the history of livestock production in the Un ited States has the cattleman experienced such a demand for his pro duct . The 109 pound per capita consumption of beef in the United States in 1968 represents a new height of acceptance of the cattle man's produce. Yet forecasters indicate that consumption of beef can and will continue to increase. The factors which have resulted in this unparal l eled accept ance of beef are associated with greater production, higher consumer earning power, relatively economical prices for beef, and the desirability of the product being produced. Desirability of beef has many different connotations in the livestock and meat industry. As used herein, it is identified in terms of those characteristics that are related to the consumer acceptability of the meat, and consequently its value. In beef, we have two such characteristics . One of these is the quality of meat; the other is the yield of salable meat as it goes across the butchers block. In my op i nion, the latter characteristic will be the major factor determining future beef consumption trends and the health of the beef-cattle indus try. Consumer demands have increased for lean meat. Over-fat, wasty carcasses and cuts have become increasi ngly difficult to market , and cutability has necessarily been emphasized . In this calorie-fat- conscious age consumers do not want fat, but desire to purchase meat without excessive quantities of fat, either exterior or interior. At the 1956 meeting of the American Society of Animal Production, Pierce et al . (1956) reported on a study of 459 beef carcasses in whi ch theY-presented i nformation relative to factors influencing yields of wh olesale and retail cuts. These s tudies indicated that there was a wide variation i n y i elds of trimme d retail c uts among al l carcasses as wel l as among carcasses of the s ame weight and grade. The factors mos t freq ue ntly associated with cut-out val ue are degree of fatness and type or conformation. In the Pierce report , conformation was positively associated with yield of retail cuts while fin i sh had the opposite e ffect. Further analyses of these data indicated that when conformation and fini s h were expressed in terms of grades, fini s h was 4 - 1/2 times as im portant as conformation in predicting yields of closely trimmed , mostly bone-in, retail cuts from round, loin, rib , and ch uc k. Goll et al. ( 1961 ) reported that the Choice, Good, and Standard grades differed significantly in the average yields of round, loin, rib, and c huck. These investigators also found that

*Professor and Chairman, Department of Animal Sc ience , Texas Technological Col l ege . Presented at the Performance Testing Field Day, Tex as Technological Co llege Research Farm, Killgore Beef Cattle Cente r , Pantex , Te xas. March 6, 1969.

1 6 finish had a greater influence on yields than did conformation. Numerous other research studies (Butler, 1957; Murphey et al., :1960; Zinn et al., 1961; Breidenstein, 1962, Brungardt an dBray, '1963; and core et tl·· 1963) have shown that, as historically ~valuated, conformation per se is not associated to any great ~xtent with yield of retail cuts. Available data indicate that there is an association between conformation and muscling in the young, unfattened animal (Greiman, 1961 ). As the animal increases rtn weight and finish the relationship decreases because of the Hnability to determine that portion of desirable conformation ~hich is due to muscling and that due to fat. I .' Thus, Zinn et al. (1961) and Zinn (1967) reported that :carcass conformaITonscore was significantly related to carcass ~rade, marbling score, and percent fat trim, and negatively !,:.elated to percent boneless primals. Tyler et al. (1964) and iMartin et al. (1966) reported that when carcass-Weight and fat !thickness were held constant, cattle with higher conformation scores had a higher cutability. On the other hand, Abraham et al . '(1968) reported data which indicated that the relationship oi' ~onformation with yield of boneless retail cuts was due to the ·interrelationships of conformation with carcass weight and fatness. ~he research data warrants the conclusion that from the standpoint !of carcass cutability, there are many desired body forms, .that ianimals differing widely in conformation will exhibit desirable !Cutability characteristics, and cattle identical in conformation ~ill vary widely in cutability. The common denominator for these interrelationships appears to be the amount of finish these animals have and the consequent ratio of muscle to fat. Most research reports indicate that as carcass weight increas es, fatness increases. Breidenstein (1962) reported a reduction in retail yield of l .42 percent for each 100-pound increase in carcass weight. Fat, however, varies between carcasses of the same weight, and it is these deviations which are responsible for wide variations in cutability. Ramsey et al. (1962) reported variations of one to 27 milli meters in fa~thlckness at the 12th rib. Differences in kidney fat were from 1.8 to 8.9 percent and separable fat of the carcass varied from 14.3 to 42.8 percent. Cole et al. (1962) reported that with weight held constant, 34 percent or the variation in separable lean of the carcass was accounted for by thickness of outside fat. Zinn (1963) reported a correlation of -.77 between percent fat trim and boneless primal cuts. As summed up by Abraham et al . (1968) fat thickness accounts for more of the variationinpercent of boneless steak and roast meat than any other single variable studied. What effect does development of carcass muscle have on cut- abi l ity? Significant but not particularly high correlations between longissimus dorsi (rib-eye muscle) area and retail yield have been reported by a number of workers. Breidenstein (1962) showed an increase of 0 . 37 percent and 0.42 percent in retail yield for steers and heifers, respectively, with a one square inch increase in loin eye area. Measurements of other muscles of the carcass have been used to estimate cutability. The muscular development of the round appears to be most closely related to cutability. Cole et al. (1960) reported that 90 percent of the variation of totai-lean was accounted for by the separable muscles of the round . Brungardt and Bray (1963) reported a correlation of 0.83 between trimmed round and retail yield. Abraham~~. (1968) reported that width of round was significantly related to retail yield while the 17 relationship with length of body and length of round was low and insignificant. What are the relationships between rate of growth and retail cutability? One must be cautious in the interpretation of research results when considering this relationship. When cattle are fed for a standard period of time, there is an inverse relationship between daily gain and muscle development (Zinn, 1964). This can probably be explained in the observation that fattening is a function of a physiological age-weight relationship and not of chronological age. Therefore, faster gaining animals fed the same period of time as slow gaining animals will deposit a greater amount of fat which expressed on a part-to-whole relationship {pounds fat to pounds of carcass) will show a positive relation ship to rate of gain (Hedrick, 1968). On the other hand, if cattle are fed to a constant weight, then the relationship of gain with muscling would be positive. Knox (1957) and Cartwright et al . (1958) have suggested that animals with a higher daily-gaTn reach a given weight more rapidly and have more lean than low gaining cattle. Hedrick et al. ( 1963) reported s ignifi cant positive relationships between rate-Of gain and trimmed primals and trimmed wholesale cuts (r=0.41 and 0.41, respectively). A correlation coefficient obtained by these workers between fat thickness and daily gain of - . 26 further suggested that faster growing cattle, when fed to a constant weight, have more lean and less fat. Also, faster gaining cattle reach a de sired slaughter weight at a younger chronological and physiological age when they still have considerable potential fo r muscle growth relative to fattening (Zinn, 1964). One would also expect the relationship between muscle development and rate of gain to im prove as the animal breeder improves the genetic base for muscle development at the expense of fat deposition . Thi s discussi on of factors influencing cutability is of little bene fit to the beef cattle producer unless he can realize some economical value from producing high cutability cattle. The value of carcass cutability at the retail level can best be illustrated by actual cut-out test. Table l presents cut-out data of two Choice grade cattle of similar carcass weight. Differences in retail value per cwt. of carcass was $7.58 or a total carcass difference of $37.63. Table l. Summary of yield grade determination and cutting test results. 14th Annual Re ciprocal Meats Conference, University of Tennessee, Knoxville, Tennessee, June, 1961

Yield Grade Determinations Carcass A Carcass B Thickness of fat, inch es 0. 4 0.9 Area of rib eye, sq. in. 11 . 2 5 8.25 Estimated percent kidney fat 3.00 3.00 Carcass weight, pounds 551. 00 558 . 00 Yield grade 3.0 5. 3 Estimated yield of boneless retail cuts 50.8 45.5 Qua 1 ity grade Choice Choice

- continued -

18 rab l e l. continued

Yield and Va lue Com2arison Percent of Price ~ ut, bone l ess Carcass Weight 2er l b. Va lue !!er hundredweight A B A B ~ump 3.76 3.59 0.89 3.35 3. 20 l ns ide Round 3. 94 3.62 0. 99 3.90 3.58 butside Rou nd 5.27 4. 17 0. 85 4.48 3. 54 ~o u nd Tip 3. 31 2.94 0. 85 2. 81 2. 50 ~irloi n Butt 4. 79 4.24 l. 39 6.66 5.89 ~trip Loin 2.87 2.61 l. 99 5. 71 5. 19 Tenderl oin 2.03 l. 74 2. 09 4 . 24 3.64 Chu ck 19.26 17 . 51 0. 69 l 3. 29 12. 08 Rib 4.86 4 .64 l. 49 7.24 6. 91 ' rota l maj or cuts 50.09 45.06

~ l ank Steak 0.55 0.58 l. 09 0.60 0.63 Bri sket 2.36 l. 74 0.89 2. l 0 l. 55 lean Trimming 16.83 13.63 0.69 l l. 61 9.40 fat 15. 32 25.26 0.03 0.46 0.76 Bone 14.65 13.52 0.005 0.07 0.07 Kidney 0 .20 0.21 0.35 0.07 0.07

Total 100.00 100.00 66 . 59 59 .0l Di fference in value per cwt . $ 7.58 Difference in total carcass value 37. 6 3 Tabl e 2. Summary of Yield Grade Determ ination and Cutting Test Results U.S. Department of Ag r iculture Bul. AMS- 416, 1960

Yield Grade Determi nation Ca rcass A Carcass B Thickness of fat, inches 0. 3 1. 0 - Area of rib eye, sq. in. 13.00 9.00 Estimated percent kidney fat 2 . 28 4.00 Carcass weight, pounds 700.00 700.00 Yield grade 2.0 6. 0 Esti mated yiel d of bone l ess retail cuts 50 . 9 42.9 Qua l i ty grade Choi ce Choice Yie l d and Value Com2arison Cut, Bo neless % of Carcass Wt. Pounds Value

A B A B A B Bo neless ma jor cuts (from round, loi n , rib, and chuck} 50 . 9 42.9 356.3 300.3 $427.56 $360 . 36 Boneles s minor cuts 8.3 7. 9 58. 1 5 5. 3 43. 58 41 . 48 Le an Tri mmi ngs l 0. 6 9.2 74. 2 64 . 4 43.78 38.00 Fat l 6. 6 26.9 116 . 2 188 . 3 2. 32 3. 77 Bone 13. 6 l 3. l 95.2 91. 7 .48 .46 Total 100 .0 100 .0 700.0 700.0 $517.72 $444.07 Difference in value per cwt. $10.52 Difference in total carcass value $73 .65 19 Table 2 shows an even more dramati c difference in cut-out value of retail cuts. This data, reported by the U.S.D.A. {1960 ) shows a retail difference of $73.65 between two Choice grade carcasses of similar weight. The U.S.D.A. official standards for grades of carcass beef now recognize these differences i~ identifying carcasses by cutability grades as well as by quality grades. Cutability grades are designated l through 5 to indicate the expected percent of bone less, closely trimmed steaks and roast from the round, loin, rib, and chuck as shown in table 3. The cutability group of a beef carcass is determined by considering four characteristics: (1) the amount of external fat ~ {2) the amount of kidney, pel vic and heart fat, {3) the area of the ribeye muscle, and (4) the carcass weight. The following regression equation shows the relationship of these factors in determining percent boneless retail c uts: Percent boneless retail cuts f r om round, l oi n, rib and chuck· 51.34 - 5.78 {single fat thickness Qver rib eye, in.) - 46 2 {percent kidney fat) + 0.740 {a rea of rib eye, sq. in.) - . 0093 {carcass weight, lbs .). or in determining cutability group: Cutability group= 2.50 + (2.50 X adjusted fat thickness , in.) + {0 . 20 X percent kidney fat) + {0.0038 X hot carcass weight, lbs.) - 0.32 X area ribeye, sq. in). Will value differences in retail cut-out of be ef carcasses ultimately benefit the producer? Not only are production costs less in producing more muscular, rapid growing cattle (fattening is a most expensive process); as the quantity of high cutability cattle on the market increase t o the poi nt where they have a significant influence on the market struct ure, the retailer and packer will pay premiums on high cutability grade cattle and discount the overfat, low cutability grade carcasses. Some packers are now buying on a c utability grade basis and the quantity of cutability gr aded cattle is increasing each month. At Texas Tech, Breidenstein and Gann (1968) have calculated that each 0.1 change in cutability grade changes average carcass value by $0.20 per cwt., or $2.00 per cwt. for each f ull unit change in cutability grade. The beef cattle producer who has during the past few years systematically improved the muscling and growth characteristics of his cattle will soon realize the benefits of his efforts in increased premiums for genetically proven meat type cattle. Table 3. Cutability Groups

Expected % cut-out Cutability from round, loin, group rib, and chuck

l 52 .4 + 2 52.3 to 50.l 3 50.0 to 47.8 4 47.7 to 45.5 5 45.4 -

20 Bibliography Abraham, N. C., Z. L. Carpenter, G. T. King and 0 . D. Butler. 1968. Relationships of carcass weight, conformation, and carcass measurements and their use in predicting beef carcass cutab ility. ii. Animal Sci. 27:604. Breidenstein, B. C. 1962. More definite system is needed to predict retail yield o f beef carcass. Nationa l Provisioner Con- 1vention Iss ue. October. . Brungardt, V. H. and R. W. Bray. 1963. Estimate of retail yield1 of the four major cuts in the beef carcass. J. Animal Sci. f2 :11 7. i Butler, 0. D. 1957. The relation of conformation to carcass ~raits. J. Anima l Sci. 16:227. I Cartwright, T. C., 0. D. Butler and Sylvia Cover. 1958 . The ~elationship of ration and inheritance to certa in production and farcass characteristics of yearling steers. J. Animal Sci. 17:540. ! Cole, J. W., L. E. Orme and C. M. Kincaid. 1960. Relation- hip of loin eye area, separable lean of various beef cuts and arcass meas urements to total carcass lean in beef. J. Animal ~ c i. 19:89. 1 Cole, J. W., C. B. Ramsey, C. S. Hobbs and R. S. Temple. 1963. ~ffects of type and breed of British, Zebu and dairy cattle on eroduction, palatability and composition. III . Percent wholesale fUts and y ield of edible portion as determined by physical and chemical analysis . J. Animal Sci. 23:71. I Goll, D. E., E. A. Kline and L. N. Hazel. 1961. In f luence of beef carcass grade and weight on yield of wholesale cuts and farcass measurements. J. Animal Sci. 20:260. i Greiman, B. J . 1961. Subjective and objective live animal and carcass evaluation and the influence of s ire, sex and hormone ~reatment on beef cattle. Ph.D. Dissertation . Univ. of Missouri, Columbia.

: Hedrick, H. B., W. E. Meyer, M. A. Alexander, J. F. Las ley, ~. E. Com f ort, A. J. Dyer and H. D. Naumann. 1963. Indices of reatiness in beef. Mo. Agri. Exp. Sta. Res. Bul. 928. . Knox, J. H. 1957. The interrelations of type, performance, ~nd carcass characteristi cs . J. Animal Sci . 16:240. , Martin, E. L., L. E. Walters and J. V. Whiteman. 1966. ~sso c iation of beef carcass con forma tion with thick and thin muscle yields. J. Animal Sci. 25:682. : Murphey, L. E. , D. K. Hallett, W. E. Tyler and J. C. Pierce. J960. Estimating yields of retail cuts from beef carcasses. J . ~nimal Sc i. 19 : 1240.

Pierce, J. C., C. L. Strong, M. M. Van Zandt and C. E. Murphy. 1956. Some factors influenci ng yields of wholesale and retail cuts from beef carcasses. Am. Soc . Ani. Prod. Minn. Ramsey, C. B., J. W. Cole and C. S. Hobbs . 1962. Relation of beef carcass grades, proposed yield grades and fat thickness to separable lean , fat and bone. J. Ani ma l Sci. 21:193 .

21 Tyler, W. E., D. K. Hallett, C. E. Murphy, K. E. Hoke and B. C. Br eidenstein. 1964 . Effects of variations in co nformation on cutability and palatability of beef. J . Animal Sci . 23:864. U.S . D.A . 1960. AMS-416 Bulletin. Zinn, D. W., H. Elliott, D. Burnett and R. M. Durham, 1961. Evaluation of U.S. D. A. beef grading methods. J. Animal Sci. 20 : 922. Zinn, D. W. 1964. Interrelationships of live performance traits and quantitative and qualitative beef carcass character istics. Pro c. Rec i procal Meat Conf. 17:43. Zinn , D. W. 1967 . Qua ntitati ve and qualitative beef carcass characteristics as i nfluenced by time on feed. Ph.D. Dissertation . Uni v. of Mis so uri, Columbia.

22 NUTRITIVE VALUE OF WAXY SORGHUM GRAIN RECONSTITUTED WITH DIFFERENT MOISTURE LEVELS L. G. Finley* and L. B. Sherrod nt rod uct ion Research over the past few years has shown that reconstitu :ion of whole dry sorghum grain to approximately 30% moi s ture 'allowed by an air-tight storage period of about 21 days has :onsistently improved efficiency of feed utilization by finish ng cattle. This improved feed conversion has resulted largely 'rom increased digestibility of both the energy and protein :omponents in the ration with reconstituted grain ground immedi- 1tely prior to feeding compared to ground dry grain. Several 1ariables such as moisture levels, storage time, and temperature luring storage could possibly influence the increased digest ibility and efficiency of feed conversion obtained by the ·econstitution process. Studies by Neuhaus and Totusek (1969) Indicate that in vitro digestibility of reconstituted sorghum irain i ncr ea se~with ea ch moisture level within the range between 13 and 35% moisture. Pantin et al. (1969) reported that neither 'ater temperature (60 vs. 1200-F-:) nor storage time (10 or 20 jays) significan tly changed the increase in diges tibility of reconstituted sorghum grain over dry grain. Th ey did note that jigestibility was somewhat higher with the grain stored for the ZO-day period than that s tored for 10 days. Further information 'ill be required to fully evaluate the importance of these variables upon the improvement in utilization of reconstituted sorghum grains. In addition, few if any data are available :oncerning reconstitution of waxy sorghum grains. Thi s investigation was conducted to determine the effects of various moisture levels upon the digestibility of reconstitu ted waxy sorghum grain rations by sheep. Procedure The waxy (3758) 1 grain was produced under irrigation at the Te xas Tech University Research Center at Pantex . The waxy grain contained a gl utenous type starch which was a lm ost entirely amylopectin compared with the non-glutenous (75% amylopectin and 25% amylase) in regular sorghum grains (Hinders, 1969) . Initial dry matter content of the grain was 88.8%. Portions of the grain were reconstituted with three levels of added moisture (10, 20 an d 30% by weight) with the air dry grain as the control. Re ~ons t i t ut io n was accomplished by placing 50 l b. of whole grain ln polyethy lene bags and adding the quantity of water necessary to bring the grain to the desired moisture level. The water and g~a in were t horoughly mixed, the air exc luded, the bags tied air t1~ht , then s tored in a dark room at about 75° F. for 21 days pr1?r ~o ~se in the digestibility trial. The bags were turned at P~r10~1c ~ntervals during the firs t five days to insure uniform d1str1but1on of the water and grain wi thin each bag. Dry matter ~ontent of the grain in the various treatments when fed is given ln table 1.

*Present address: Mesa, Arizona 1 Funk Bros . variety. Mention of proprietary products does not necessarily imply endorsement of these products over other comp arable products. 23 Table 1. Chemical Composition of Rations Added moisture, % 0 10 20 30 Grain, % dry matter (OM) 88.8 79.8 71. 0 60 . 6 Ration, % OM 89.2 82.2 75. 1 66.9 Cmposition, OM basis,% Organic matter 96.9 97.0 97. l 97.2 Ash 3. l 3.0 2.9 2.8 Crude protein 14 . 7 14.7 14.6 14. 7 Ether extract 2.5 2.5 2. 1 2.4 Crude fiber 11. 5 11. 3 1 0. 6 11. l N-free extract 68.2 68.5 69.8 69.0 Calcium 0.27 0.24 0.26 0.25 Phosphorus 0.27 0.28 0.27 0.26 Gross energy, kcal . per gm. OM 4.344 4.332 4.320 4.340

Twenty-four crossbred wethers averaging 103 lb. were placed in metabolism stalls and randomly assigned six per treatment to the four moisture levels for the trial involving a seven-day adjustment period followed by seven-day preliminary and collection periods. All animals were initially fed t he respective grains at levels to equal a ration consisting of 52% air-dry grain equiva lent, 45% cottonseed hulls and 7% supplement in the total daily intake of 1200 gm. fed in two feedings. Composition of the supplement in percent was: cottonseed meal, 70.0; urea, 11 . 3; trace-mineral salt, 8. 1; calcium carbonate, 8.1; elemental sulfur, 1. 7; with 56.0 mg. ch lortetracycline and 32,600 IU vitamin A per lb . The cottonseed hulls were reduced by about 5% per day with commensurate increases in the grains until the animals were con s uming 1,200 gm. per head daily composed of 73% grain (air-dry basis), 20% hulls and 7% supp lement fed in approximately equal portions twice daily. Chemical composition of the final rations is given in table l . Feed intake was then held constant during the remainder of the trial. All grains were fed whole and the ration components mixed by hand just prior to each feeding during all periods of the trial. Dry matter content in the grains was determined periodically throughout the trial and thes e data used to maintain constant daily intake. Water was available free choice. Ration components were sampled at each feeding; total wet feces were individually weighed, sampled (10% ali quot) and com posited daily; and total daily urine diluted to a constant volume then a 100 ml. aliquot composited for analysis. Wet grain and fecal samples were frozen and urine samples refrigerated until analyzed. Proximate analysis of feed and feces, and urinary ni trogen analysis were conducted by A.O.A.C. (1960) methods. Gross energy determinations were made using a Parr oxygen bomb, adiabatic calori-meter. Calcium and phosphorus were determined by atomic absorption spectrographic procedures (Warner, 1970). True protein digestibility was calcul ated using the value of 0.45 9m. metabolic fecal nitrogen per 100 gm. dry matter intake (Blaxter, 1964). Statistical analyses were by anal ysis of variance.

Results ~Discus s ion Digestibility data are presented in table 2. Dig estibility of organic matter, non - protein organic matter, nitrogen-free extra< and gross energy was not affected s ignifi cantly by 10% added moisture but was improved by both the 20 and 30% levels. Digest ibility of these compo nents was expressed by a s ignificant

24 p < . o5) linear response. Crude fiber digestibility tended to - ~crease slightly with higher added moisture levels. Both crude nd true protein digestibility were improved only with the 30% -evel of added moisture . Nitrogen retention was not affected ignificantly by treatment. 'able 2. Sheep Digestibility of Waxy Sorghum Grain Rations Con taining Grain Reconstituted With Different Moisture Leve l s

\dded moisture, % 0 l 0 20 30 1aily OM intake, gm. 1070.5 1068.2 1069.6 l 061. 4 1igestibility, OM basis, % } Orga nic matterc 71 . ga 70.9a 73.6a,b 75.4~ · Non-protein organic matterc 75.5a 73.7a 77.la,b 78.\ Crude protein 52 . l a 55 . oa,b 53.6a 57 . 9b True protein 71 . 3a 74. 2a ,b 72.8a 77.0b Ether extract 83.5a,b 80.oa 80 . l~ 85.2 b Crude fiber 37.oa 37.8a 32.2 b 35.6a, N-free extractC 81. 7a 79.5a 83. 5a • 85.2b Gross energyc 68.7a 67.8a 70.4a,b 72.lb laily nitrogen balance, gm. · Nitrogen intake 25.16 25 . l 0 25.02 24.66 Nitrogen in feces 12.05 11. 30 11. 62 10.37 Nitrogen in urine l 0. 11 10 . 98 10.70 11. 28 . Nitrogen retention 3.0 2.82 2.70 3.01 ligestible energy, kcal. per 2.984 2.937 3.041 3. 129 1 gm. OM rDN, OM basis, % 72.2 71. 3 73.5 75.9

a,bMeans on the same line having different superscripts dif fer significantly (P<:'. . 05) . C[ffect of moisture levels was expressed by significant (P <. 05) linear response. The data reported herein are in agreement with results ob ~ained by Neuhaus and Totusek (1969) who found that in vitro ~ i gestibility of reconstituted sorghum grain improveO-w""f"t"fleach higher moisture level within the range of 13 to 35% total moisture. In the present study, digestibility was not improved between the !ir-dry (11.2% moisture) and the first level of added moisture ( 20.2%), but increased with each of the two higher levels (29.0 ~nd 39.4%) in reconstituting waxy sorghum grain. The present ~esult s also indicate that digesti bi l ity of waxy sorghum grain ~as improved by reconstitution similar to that reported with regular sorghum grain (McGinty et a l ., 1967; Buchanan-Smith et al., 1968 ; Pantin et al., 1969)-:- However, the total increase rn dTgestibility was somewhat less than has been reported by these p th~r inves t igators. This might be partially explained on the basis that sheep were used in the present s tudy while most of the other data were obtained with cattle. Buchanan-Smith et al . , (19~8) reported that increases in digestibility of sorgnuiil"grain r~tions with various processing methods were less with sheep than with cattl e primarily because digestibility of the unprocessed control grai ns was considerably higher by sheep. This possible influence of higher digestibility of the air-dry grain by sheep c omp~red with cattle might account to some extent for the lower magnitude of improvement with reconstitution ob s erved in the study reported herein. It was observed that s ome separation of the grain and water occurred initially with the high level (30%) of added moisture.

25 This probably was because the grain co uld not absorb the water rapidly enough to prevent some liquid water from collecting in the bottom of the bags. Comp lete water absorption was obtained by periodically turning the bags which allowed remixing of the grain and water . Thi s water-grain separation shou ld be considered in cases where whole grains a re reconstituted on a commercial scale s ince subsequent mixing would be considerably less feasible than was the case in this experiment . Summary Digestibility studies were conducted with sheep to eval uate the effects of different levels of added moisture upon the di gestibility of reconstituted waxy sorghum grai n. Whole waxy grain was reconstituted in polyethylene bags with 0 (air-dry, control), 10 , 20 and 30% added moisture by weight. Th e different grain treatments were fed on a co nstant air-dry intake basis in rations composed of 73% grain, 20% cottonseed hulls, and 7% protein-mineral supplement. Digestibility of the major energy components was not affected s ignifi cantly by the first level of added moisture then i nc reased with each of the two higher l evels. Both crude and true protein digestibility were almost constant with the 0, 10 and 20% added moi sture levels, then increased with the 30% level . Nitrogen retention was similar with all treatments. Literature Cited A.O.A.C. 1960. Officia l Methods of Analysis (9th ed.). Association of Official Agricultural Chemists. Washington, D.C. Blaxter , K. L. 1964 . Metabolism and metabolic body size: A study with cattle and sheep. Mo. Agr. Exp. Sta . Sp. Rpt. 43:8. Buchanan-Smith, J . G. , R. Totusek and A. D. Tillman. 1968. Effect of methods of processing on digestibility and utili zation of grain sorghum by cattl e and sheep. J. Anima l Sci. 27:525. Hinders, R. M. 1969. Personal communications. Funk Bros . Seed Co., Lubbo ck , Texas. (Present address: Producers Grain Corp., Amarillo, Texas).

Pantin, E. J., J. K. Riggs and E. J. Bowers. 1969 . Water temperature and s torage time as factors influencing utilization of reconstituted grain sorghum. Texas Agr. Exp. Sta. Co nsolidated Publ. PR -2676 - 2695:7.

McGinty, D. D., L. H. Breuer a nd J. K. Riggs . 1967. Digest ibility of dry and recons t ituted sorgh um grain by cattle. J. Animal Sci. 26:223. (Abstr.). Neuhaus, V. and R. Totusek. 1969. Factors affecting in vitro digestibility of high moisture sorghum grain. J. Animal Sci. 29:167. (Abstr.). Warner, M. H. 1970. Personal communications. Ohio Agr. Res . and Dev. Center, Wooster , Ohio. Acknowledgment Thi s study wa s partially supported by Funk Bros. Seed Co., Lubbock, Texas. This assistance i s gratefull y appreci ated.

26 CONTINUING REPORT ON PROJECT ENTITLED "A COMPARISON OF BEEF CATTLE SELECTED BY FOUR DIFFERENT CRITERIA" K. R. Hansen, R.H. Klett and D. W. Zinn Introduction Thi s project was initiated i n 1955 with the objective of determining the outcome of various selection programs when using gain and conformation as criteria . Procedure In 1955, a herd of 100 uniform, grade Hereford cows were randoml y allotted to four groups of 25 cows each. Selection criteria to be followed were set up as follows: A - Herd Ga i n i n g ab il i ty and conformation receive equal emphasis. B - Herd - Selection based on gaining ab i l i ty only. c - Herd - Selection based on conformation alone. F - Herd - Selection based on low gaining ability . The bulls used in the A, B and F herds have come from per formance bull tests and were selected from the top 10% on gain plus prime minus or better conformation, to 10% on gain alone, and bottom 10% on gain of bulls on test for each of the three herds, respectively. The C herd bulls have been selected f rom the high placing individuals at various livestock shows . A bull is used for two years, then replaced. He i fers are selected on the same criteria and go back into the herd from which they came. Approximately 20% of each herd has been replaced each year. Each herd is treated ali ke during the year. The only time herds are separated is during the 78 day breeding season. During lactation cows are grazed on native grass and sudan pasture. Steers from the 1968 calf crop were fed in two groups. Four steers were randomly selected from each herd and individually fed. The remainder were group fed. Results !!lE. Discussion 1969 adjusted 205 day weaning weights varied 15% between herds with 445, 476, 460, and 415 lb. for the A, B, C, and F herds respective ly. Table 1 contains feedlot performance of the steers from the 1968 calf crop both group ( GF ) an d individually (IF) fed . In both cases , the herd selected for high gain (herd "B") gained faster than any of t he other three herds.

27 Table l. Feedlot performance of 1968 steers group and individual ly fed .

Herd A B c F GF IF GF IF GF IF GF IF Average daily gain 3. 17 2. 01 3.40 2.39 3. 19 2.29 2.82 2.17 Feed efficiency 8 . 39 7.45 6.75 7.62

Feed efficiencies of i ndividually fed steers favored the herd se l ected for conformation (C) with 6.75 lb . feed/lb. gain. Summary The "B" herd weaned 7% and 15% heavier calves when weights were adjusted to 205 days tha n the A and F herds, respectivel y. In the feedlot, the herd selected for high gain (B) had higher gains than all other herds when steers were group or individually fed.

28 EFFECT OF TWO FEEDING REGIMES UPON PERFORMANCE OF EARLY WEANED CROSSBRED BULLS AND HEIFERS K. R. Hansen Introduction Research has shown that an inadequate nutritional level of lactating beef cows can substantially reduce weaning weights and calf crop percentages . This research, still in progress, wa s initiated to study alternative methods of managing calves when cow nutrition is a problem, as in years of drouth or when twins occur. Procedure Twenty-nine 1/2 Jersey 1/2 Hereford calves (16 bulls and 13 heifers) averaging 154 lb. from first calf Hereford cows were wea ned at an average age of 78.4 days. At wea ning, calves were given routine vaccinations plus one million I.U. Vitamin A. The calves were placed in drylot and fed an all-concentrate ration (table 1) for 56 days. At the end of 56 days, 1/2 of each sex group was placed on a 20% roughage ration (table 1). The rations were made isonitiogenous by the introduction of urea. Roughage adjustments were made on days 112 and 168 to 15% and 10%, respectively. Table l. Exper imenta l Rations

Period, 1-56 57-llZ- ~ 168 169- Ingredient A-C Roughage A-C Roughage A-C Roughage Mi lo 77. 50% 8 7. 1 5% 63 . 15% 87. 15% 68 . 15% 93 .30% 82 . 60% Cottonseed meal 20.00 10.00 14.00 10.00 14.00 4.30 4.90 Urea . 40 .40 .40 . 40 .70 .80 Cottonseed hu 11 s 20.00 15.00 10. 00 Cal ci um carbonate 1.0 1.0 l . 0 1. 0 1.0 .50 .50 Trace- mineral salt 1.0 1 .0 1.0 1.0 1.0 1. 0 1. 0 Sulfur . 1 . 1 . l . 1 . l 0 . l Vitamin A . 15 . 15 . 1 5 . 15 . 15 .028 .028 Aureomycin 11 1 0 II .30 .20 .20 .20 .20 . 035 .035

Re s ults and Discussion During the first 56 days after weaning, the bul l s gained 2 .08 l b./day and the heifer s gained 1. 75 lb ./day with an average feed effi ciency for both groups combined of 3.80 lb. feed/1 b. gain (table 2) for a cost/lb. gain of only 9.5¢.

29 Table 2. Weaning data and feedlot performance for first 56 days.

Characteristic Bulls Heifers Total or/average Age at weaning, days 76 . 6 80.8 78 . 4 Weaning weight, lb . 157 . l 1 51 • 1 154 . 6 Av. daily gain, lb. 2.08 1. 75 l. 94 Feed effici ency 3 .80 Av. daily consumption 7. 38 Feed cost/lb. of gai n for 1st 56 days 9. 5¢

Table 3 contains a s ummary of performance from day 57 , at which time groups were separated by sex and placed on two feeding regi mes, through 224 days. Average daily gains were only slightly different within sex groups . Efficiency of feed utilization was in favor of the two groups receiving the all-concentrate ration with 6.07 and 7.81 lb. of feed/l b . ga i n for the bulls and heifers, respectively, as compared to 7.20 and 8 . 12 lb . for bulls and heifers receivi ng roughage . Table 3. Feedlot p-e rformance day 57 through 224 .

Bull s Heifers Cha racte ri s tic All-Con. Roughage All-Con . Roughage No. head 8 8 6 7 Av . daily gain 2.02 2. 12 1 . 81 1.83 Feed/lb . of gain 6.07 7 . 20 7. 81 8.12 Av . daily feed consump . 12.28 15 . 26 14.14 l 4. 88 Feed cos t /lb . gain 13.63¢ 15. 40¢ 17 . 53¢ 17 .3H

At 218 days , the early weaned ca l ves weighed 433 lb. which wa s 49 lb . heavier than the weighted ave r age for the pr evi ous three years of normal weaned calves weigh i ng 384 lb . at 217 days. Summary It appears there may be some advantage to early weaning calves in order to maintain a high nutr itional level . The calves gained very efficiently at 3. 80 lb. fee d/lb . gain duri ng t he first 56 days . The cal ves receiving t he al l-concentrab ration were lOi mo r e effi cient in their gains than those r eceiving. roughage from day 57 through day 224 . Average daily ga i n varied only sl i ghtly within sex groups between treatments.

30 THE USE OF CROSSBREEDING IN COMMERCIAL BEEF PRODUCTION K. R. Hansen Introduction Results of previous studies indicate that the most efficient period in the growth curve of the bovine is in the early stages of growth (birth to approximately one year of age). At this t-ime, provided adequate nutritional levels are maintained, the most ef ficient production can be realized. _Efficiency of production is becoming the key word in the livestock industry. Without this factor the growing industry cannot survive in a society of in creasing competition. This study was undertaken as a demonstration of the possible increases which can be made in efficiency of beef production through crossbre~ding. Procedure In 196B, 45 crossbred females 16 - 1/2 Charolais 1/2 Hereford (CH); 15 - 1/2 Charolais 1/4 Hereford 1/4 Brahman (CHB); 8 - 1/2 Brown Swiss 1/4 Charolais 1/4 Hereford (BS) and 6 - 1/2 Brown Swiss 1/4 Charolais 1/8 Hereford 1/8 Brahman (BS) , were allotted according to age and breeding into two groups. One. group was bred to a Hereford bull selected for gain from the top ten per cent of a 140 day gain test and the other group to a Charbray bull . The cows were maintained in separate pastures for breeding after which they were combined and managed together through gesta tion and until the calves were weaned. During lactation the cows grazed native grass, sudan and small grain pastures. No creep was provided for calves. An attempt was made to creep feed calves, although a creep large enough to accommodate calves did· not restrict the entrance of cows ~o this practice was discontin ued after one week.

Results ~Discussion Weaning data for calves based on sire are presented in table· 1. Weaning weights were 552 lb. and 603 lb . for the 1/2 Hereford and 1/2 Charbray calves, respectively. This is a 9. 2% ad vantage in favor of the Charbray sired calves. Weight per day of age differences were comparable to that of weaning weight with a 9.0% advantage for the Charbray calves. Twenty-two of the twenty three cows bred to the Charbray calved , one calf died and one cow produced twins for a calf crop of 95.7%. Nineteen of the cows bred to the Hereford bull calved and all cafves were weaned for a calf crop of 86 . 4%.

31 Table l. weaning data for 1/2 Hereford and 1/2 Charbray calves from 1968 calf crop.

SIRE Hereford Ch a rb ray No. Head 19 22 Av. age at weaning, days 217 218 Weaning wt. al l calves, lb. 552 603 Weight/day of age, lb. 2.54 2. 77 W.W. steers, l b. 548 653 Wt ./day of age - steers, lb. 2.57 2. 91 W.W . heifers, lb. 557 585 Wt./day of a9e - heifers, lb. 2.52 2. 71 Calf crop (%) 86.4 95.7 lb . of calf/cow 476 . 9 577. l

Table 2. Production based on breed of dam within sire group .

Si re Hereford Charbra_}'. Dam 1 CH CHB BS CH CHB BS No . cows 8 7 7 8 8 7 No . calves 7 7 5 7 9* 6 Age at weaning, days 216 228 206 211 225 215 Weaning wt., lb. 542 575 536 607 585 627 Cow wt., lb 1304 1283 1248 1394 1346 1230 % calf crop 2 87.5 l 00 .o 71. 4 87.5 l 12. 5 85.7 % Prod. body wt. 39 . 6 40.8 42.7 43.5 43.5 48.9 lb. calfI cow 474 575 383 531 658 537 C-Charolais; H-Hereford; B-Brahman; BS-Brown-Swiss. 2calves weaned to cows exposed . *Set of twins . Production based on breed of dam within s ire group is p resentel in table 2. The CHB cows produced more pounds of calf per cow than the other two groups with 575 and 658 lb. of Hereford and Charbray calves, respectively . The highes t producing cow (CHB) weighed 1165 lb. and produced twins (Steer and heifer) that weighed a total of 936 lb . at 241 days of age or 80.3% of her body weight. The heaviest weaning calf (1/2 Charolais steer) wa s also from a CHB cow and weighed 750 lb. at 216 days of age. Production based on the breeding of dam is presented in table 3. Based on 205 day adjusted weights the BS cows produced heavier calves than either the CH or CHB at 570, 556 and 533 lb., respect ively. However, the CHB cows weaned the higher percent of calves at 106 .7% compared to 87.5 and 78.6% for the CH and BS, respectively.

32 Table 3. Production based on breeding of dam.

Breed of Cow Characteristic CH CHB BS No. cows 16 1 53 144 No. calves 14 16 11 Age at weaning, days 213 226 211 Weaning weight, lb. 574 581 586 205 day adjusted wt . , lb . 55 6 533 570 . Cow weight, 1b • 1352 1317 1239 % Prod. of body wt. 42.5 44. 1 47 .3 lb. of cal f~cow act. 502 620 461 % calf crop 87.5 J 06. 7 78.6 1c-Charolai s; H-Hereford; B-Brahman; BS-Brown Swiss. 2cows exposed to calves weaned . 3one set of twins. 4one calf die d from pneumonia. Summary When 45 crossbred cows (16 -1 /2 Cha ro lais 1/2 Hereford; 15 - 1/2 Charolais 1/4 Hereford 1/4 Brahman; and 14 - 1/2 Brown Swiss) were allotted into two groups and mated with Hereford and Charbray bulls, the 1/2 Charbray calves were 9.2% heavier at weaning than the 1/2 Hereford calves. The CHB cows produced the most pounds of calf per cow (620 lb./cow) and weaned the largest percent of calves at 106.7%. The BS cows weaned the heaviest calves when weights were adjusted to 205 days of age.

33 EVALUATION OF ADDED BACTERIAL ENZYMES PLUS BACTERIA UPO N UTILIZATION OF GROUND RECONSTITUTED SORGHUM GRAIN BY FINISHING BEEF CATTLE K. R. Hansen and L. B. Sherrod Research has shown that reconstitution of whole grain at about 30% moisture resulted in an improvement in feed conversion of 13 to 27% (Pantin et al., 1969 and Hale et al., 1969) with finishing beef cattle:- Reconstitution of ground sorghum grain has given considerably less improvement in efficiency of feed utilization (Marion et al., 1969) . Recently, a technique has been developed to provide supplemental amylolytic, proteolytic, and celluloytic enzyme activity from bacterial sources in conjunc· tion with bacteria which further produce these enzymes for increased degradation during reconstitution of ground sorghum grain . This study was conducted to evaluate the effect of adding these preparations to reconstituted ground sorghum grain upon feedlot performance and carcass traits of finishing beef cattle. Procedure Dry rolled sorghum grain was reconstituted at about 37% moisture, including moisture in the air dry grain, both with and without the bacterial enzymes and bacteria which produce these enzymes. Bacteria and enzymes. were added to the water just prior to grain application. The reconstituted grains were stored in air-tight plastic units of about 30 tons air-dry grain each for five weeks. Samples of the grains were taken periodically and dry matter determined to insure accurate dry matter co ns umption data . Dry matter data are presented in table 1. Table 1. Average Dry Matter Percentage of Re consti t uted Grains

Grain Treated Untreated Grain, % dry matter 62. 8 63.7 Ration, % dry matter 66.2 66.9 Ration, % air dry matter 73 . 6 74.3

Fifty steers weighing an average of 601 lb. were individually identified, weighed, and randomly allotted into t wo main treat ments: (1) ground reconstituted grain treated with the enzyme bacteria preparati on, and (2) untreated ground reconstituted grain, with five replications of f ive animals per treatment for a 130-day feeding study . All steers received a 30 mg. implant of diethyl sti lbestro l at the initiation of the study. Both rations were full-fed in bunks and contained 83.7% grain (a i r-dry basis ), 6.3% supplement, and 10.0% cottonseed hull s. Supp lement compo sition is pres ented in table 2. Respo nse criteria were average daily gain, feed consumption, feed efficiency, and various carcass traits.

34 Table 2. Composition of Supplement Ingredient Percent ·cottonseed meal 69.93 Urea 11. 41 Trace-mineral salt 8 .14 Calci um carbonate 8. 14 .Elemental s ulfur 1.59 ;Aureomycin l O 0.56 Vitamin A 30 0.23

•Results and Discuss i on . Performance data are presented in table 3. Average daily gains ~ere 2.90 and 2.73 lb. on a live-weight basis, and 2.14 and 2. 11 :lb . on a carcass basis for the steers fed the treated and untreated ;grains, respectively. This represents an increase of 6.2% with the ·treated grain on a live-weight bas is , and 1.4% on a carcass basis. ~ Efficiency of feed convers ion followed similar trends with an dmprovement of 7.2% on a live-weight basis and 2.3% on a carcass :basis with the treated grain. None of the differences in animal .performance observed between the two treatments were statistically ,. significant. Carcass traits were comparab le between treatments. These results suggest that use of specific biological preparations ·in the treatment of various feedstuffs may potentially provide .meth ods for improving efficiency of feed conversion in finishing beef cattle. Table 3. Feedlot performance and carcass traits .

Characteristic Gr. Recon. Treated Gr . Recon : Untreated Number head 25 25 ' lnit. wt., lb. 590 612 '. Final wt., lb . 965 966 ;Days on feed 130 130 (Avg. daily cons. 20.05 20.24 .Avg. daily gain, lb. 2.90 2.73 :Feed efficie9cy 6.91 7.41 ·care . A.D.G. 2.1 4 2.11 Eff . of care. gain 9.37 9.59 Warm care. wt . 603 . 1 610.8 Ma r bling sc~re2 4.5 4.6 'final grade 11.l 11.2 Dressi ng percent 62.5 63.2 :Fat thickness, in. 0.51 0.53 '. Liver abscesses l 5 1 calculated assuming initial dressi ng percent of 55. 2Slight 4, Small 5, etc. 3 Good plus= 11, choice minus = 12, etc.

35 Summary A finishing trial was conducted with steers to compare reconstituted ground sorghum grain treated with bacterial enzymes and bacteria which produce these enzymes at the time of recons ti tution with untreated reconstituted ground sorghum grain. The grains were fed in rations containing 83.7% grain (air-dry basis), 6.3% protein-mineral supplement and 10.0% cottonseed hulls for a 130-day feeding period. The treated grain provided an increase of 6.2% in average daily gain and 7.2% in feed conversion on a live weight basis compared with the untreated grain. The improvement ii both gain and feed efficiency was somewhat less when expressed on; carcass basis. Carcass traits were similar with both treatments. Literature Cited

Hale, W. H. , B. Theurer, T. Loynachan, B. Tay lor and J. Kuhn . 1969. Reconstituted milo for fattening cattle. Arizona Agr. Exp. Sta. Series P-16 :2-1. Ma r ion, P. T. , S. P. Hammack and L. M. Schake. 1969. Reconsti tuted grain from trench si l os in cattle rations . Proc. Western Sect. Am. Soc. Animal Sci. 20:265. Pantin, E. J., J. K. Riggs and E. J. Bowers. 1969. Water temperature and storage time as fa ctors influencing uti l ization of reconstituted grain sorghum. Texas Agr . Exp. Sta. Consolidated Publ. PR-2676-2695:7. Acknowledgment This study was partially supported by a grant from Reliance Chemicals Corporation, Houston, Te xas. This assistance is grate fully appreciated.

36 MELENGESTROL ACETATE AND CHLORTETRACYCL INE, ALONE OR IN COMBINATION FOR FINISHING HEIFERS K.R. Ha nsen, L.B. Sherrod and R.D. Furr* Introduction 1 Th e use of all-concentrate finishing rations has gained consid- 1erable acceptance by the beef industry in recent years. Research ~as indicated that thes e high energy finishing rations generally result in superior feed efficiency, acceptable gain and carcass RUality comp ared to conventional rations containing 10 to 25% roughage . However, the use of these high energy, all-concentrate finishing rations ha s resulted in greater condemnation of livers attributable to abscess es. Research has indicated that continuous 1ow level feeding of ch lortetracycline (CTC) or other comparable ~ntibioti cs generally results in a significant reduction in ab ~cessed livers for cattle receiving a high energy finishing rati on. The inclusion of Melengestrol Acetate ( MGA) in f inishing rations for heifers has generally resulted in increased gains and favorab l e feed conversions compared to control groups receiving ho MGA. However, data are limited regarding the possible inter action which might exist between MGA and CTC in all-concentrate finishing rations for he ifers. The objectives of this study were to: (1) evaluate the affects of including either MGA or CTC, alone or in combination, in an all-concentrate finishing ration for beef heifers, and (2) deter mine whether there i s an interaction between MGA and CTC in an all-concentrate finishing ration for beef heifers, when the inci pence of abscessed livers is used as the primary critera. Procedure , Two hundred heifers weighing approximately 570 lb. were indi yidually identified, weighed and randomly allotted to four treat ments: (1) control-no MGA or CTC; (2) 0.5 mg./hd/day of MGA : (3) 350 mg. and 70 mg. / hd /day of CTC for the first 30 and subsequent JlO days, respectively; and (4) 0.5 mg./hd/day of MGA; 350 mg. and 70 mg./ hd/ day of CTC for the first 30 and subsequent 110 days, respectively, for a 140-day feeding period. The rations were ' dentical with the exception of the above mentioned treatments ~nd consisted of 93.9% grain sorghum, 4.3% cottonseed meal, 0.7% urea, 0.5% CaCo 1 , 0 . 5% trace mineral salt and 0.1% sulfur. Vitamin A wa s a~ded to supply 2000 I.U./lb. of ration. All rations were fed in self-feeders. The MGA pre-mix (soybean mill feed carrier containi ng 100 ~g.MGA /l b.) and CTC pre-mix (10 gm. / lb.) were mixed with cotton seed meal to form a supplement. This supplement was mi xed in the comp~ete ration, and fed in an amount, based on consumption, to p rov~de 0. 5 mg._MGA and 350 or 70 mg. CTC per head da i ly as required accordin~ to treatment. Supplements were sampled and analyzed at the time of manufacture to assure proper additive 1mounts. Supplement analysis are presented in table 1.

*Present address Hi-Pro Feeds, Inc. , Friona, Texas . 37 Table 1, Supplement Analysis for Melengestrol Acetate and Chlortetracycline .

Sup plement containing: CTC Al one MGA Alone CTC-MGA comb inati Ingredient CTC MGA CTC MGA Analysis1 205 . 3 1 . 31 197. 1 1 . 24 % of Theory 2 105 94 101 89

1Average of five samples taken throughout feeding period. 210 - 120% considered wi thin comp l iance. Results and Discussion

The combination of MGA and CTC (treatment 4) wa s s ignificant~ (P . 05) higher for average da ily gain, than either the control (treatment 1) or CTC alone (treatment 3) with gains of 2.78, 2. 53 and 2 . 46 lb . , respectively. No signifi cant differences were ob served i n either feed con s ump ti on or effi ciency al though treatmenl 4 consumed about 7, 3, and 8% more feed than treatments 1, 2 and 3, respectively. Feed efficiency, on live bas i s, al s o slightl y favored treatment 4. A summary of feedlot performance is presenb in Table 2. Tab l e 2. Summary of Feedlot Performance of Heifers .

Treatment Characteristic Control (1} MGA( 2} CTC{J} MGA-CTC(4) 1 No. head 48 47 46 46 Initial weight l b. 568 562 582 573 Final weight, lb. 923 b 928 ab 930 b 961 a Average daily gain, lb. 2. 53 2.60 2.46 2.78 Average dai l y feed consumption, lb . 20 . 44 21 . 24 20. 34 21. 91 Feed efficiency 8. 11 8. 1 7 8.27 7.94

1 Control - 2 heifers cal ved and were removed. MGA - 2 heifers calved and were removed, l heifer pregnant at s l aughte r . CTC - 4 heifers calved and were removed. MGA-CTC - l heifer died , 1 heife r pregnant at s laughter, 2 heifers calved and were removed. , a,bMeans on the same line bearing di fferent s uperscript let· ; ters are significantly different (P<.os) ;

Treatment 4 maintai'ned the advantage i n daily gain when cal· I culated ~n a carcass basis; however, the co ntrol group was s light: ly superior to other treatments for effi ci ency of carcass gain. The differences i n efficiency of feed utilization on both a live : and carcass bas is were only slight. 1 T~ere were no significant differences in dressing percent , marbli ~ g or carcass grade. A s ignificant difference was found in fat thickness over the Longissimus dorsi muscle between the 12th and 13th rib. This difference wa s possibly due to the accelerated 38 ~in of treatments 2 and 4 above treatment 1 .

Liver abcesses, as might be expected, were 78% fewe~ ~n treat ten t s receivi ng antibiotic (3 and 4) than ~hose not rece1v1~g ~ ntibiotic (1 and 2). No adverse interact1on was apparent l ~ the iGA- CTC combi nation treatment. Perf ormance on a carcass bas1s and ~ summary of carcass traits are presented in tabl e 3. a -able 3. Summary of Carcass Traits of Heifers.

Treatment :ha racteri st i c Control(l) MGA (2) CTC ( 3) MGA-CTC( 4) 10. head 48 47 46 46 , ve ~ age dajly care . :garn, lb . 2.03 2.09 l. 96 2. 15 ifficiency of care. '. ga in 10.07 10. 16 10 .38 10. 19 trm care . wt . 603.7 609.3 602.4 623.7 ressing2percent 65.4 65.7 64 . 8 64.9 larb l ing 3 5.6 5.6 5.4 5.5 lar c. grade 12.2 b 12.4 a 12. 1 ab 12. 2 a :at thickness, in . .52 .65 .60 .66 t.iver abscesses, % 31. 2 1 9. 1 15. 2 13.0

1calcul ated assum ing an i nitial dressing percent of 56. 3Slight=4, Sma l l =5, etc. Ggod plus=ll, Ch oice minus=l 2, etc . a, Mean s on the same line bearing different superscript letters are s igni f icantly different ( P<.05) An examination of the ovaries at time of s laughter showed t ha t 100% of the control and 94% of the CTC heifers were in some stage !f ova development , while none of the MGA treated heifers s howed tvarian activity. iumma r y Two hundred hei f er s were allotted to fou r treatments in a 140-day feeding t rial to determine the effects of MGA on perfor pance and to evaluate a possible interaction between MG A and CTC hen fed in combination. Heifers receivi ng MGA gained faster {,han those not receivi ng MG A. Differences in effi ciency of feed ~ti lization , on both l ive and carcas s basis , were variable a nd onl y ilight. Fat th ickne ss meas ureme nts were fo und to be significantly ligher in treatments fed MGA than the control . Liver abscesses ;ere 78% fewer whe n CTC was fed. There were 47% fewer ab scesses !hen CTC was combined wi th MGA than when MGA was fed a lone. No 1dverse interaction wa s f ound due to the combining of MG A and CTC then abscessed livers and performance were used as primary criteria. lone of t he heifers r eceiving MGA s howed any ova rian acti vity upon ;laughter while 100 and 94% of the control and CTC, respectively , lere i n some s tage of ova development . lcknowledgment • This s tudy wa s partially s upported by a grant from The UpJ ohn .o . Inc ., Kalama zoo, Mi chigan . Thi s assistance is gratefully lppreciated .

39 INFLUENCE OF PH~SPHORUS FERTILIZATION LEVELS UPON YIELDS ANO ON THE AVAILABILITY OF IRON AND ZINC WITH IRRIGATED GRAIN SORGHU Dale Hollingsworth, J.L. Green and William F. Bennett** Introduction Grain sorghum production on the High Plains of Texas has increased rapidly through the use of hybrid sorghums, fertilizers and i rrigation. The native phosphorus (P) levels are not high arn yields of grain sorghum when P is added appear lower than optimum for the available water. The application of P is known to suppr~ the uptake of both iron (Fe) and zinc (Z n) by plants in a numberc soils. This study was conducted to determine: (1) effects of P fertilization levels, and (2) whether P applications induce micr• nutrient deficiency with irrigated grain sorghum. Procedure Two full season varieties of grain sorghum were planted on Pullman silty clay loam soil having "A" slope and common previous treatment, in a split-plot experiment involving eight main plots. Ea ch main plot wa s eight 40 - in. rows ap proximately one-half mile long with four equal sub-plots within each main plot. Pho sphorus (0-46-0) was applied at the rates of 0, 200, 400, and 800 lb. of· P205 per acre as the main plots, with sub-plot foliar applicatioM of 2 lb . sulfate salt of Fe, Zn and Fe-Zn (2 lb . of each) in 20 gal. water per acre on each f ertilizer treatment. The seedbed was. prepared by standard procedures with nitrogen banded at a depth oi 6 in. in the sides of the furrow bed~ (20 in. between bands) at") rate of 185 lb . of N per acre. Phosphorus wa s applied with a b"a cast spreader and incorporated into the soil by disking prior to bedding . The grain sorghum was planted at the rate of 12 lb. per· acre in 10 in. double drill rows on top of the furrow beds . Herbi· cides were incorporated into the soi 1 for weed control. Five irrigations (4 acre in. pe r application) were applied during the growing season. Yield data were obtained by combining the middle four rows of each sub-plot .

Results~ Discussion Sorghum yields varied from 5117 to 6818 lb. of grain per ac" (table 1). The higher yields with P fertilization alone occurred at the 200 lb . level of P2o . Phosphorus application at the high~ rates (400 and 800 lb. of P~o 5 per acre) reduced yields s lightly. Yi elds were increased in seven of the eight treatments when Fe was applied by foliar application. This includes the zero rate of P fertilization indicating that an Fe deficiency in Pullman t soils may reduce yields. The maximum yield benefit with Fe occu~ red at the higher levels of P 0 per acre when both varieties we" considered. Application of F~ ~esulted in s ligh tly less increase in yield at 800 lb. of P;i0 than at 400 lb . P o per acre based on . the average of both varietTes5 (table 1). 2 5

*This research was supported by the Killgore Research Center, West Te xas State University, Canyon, Te xas **Assistant Agronomist, Texas Te ch Univers ity Research Center, Pa ntex, '.exas . and Asso ciate Professor of Agriculture, West Texas t State Un1vers1ty, Ca nyon, Texas and Associate Professor Dept. of n Agronomy, Texas Tech University, Lubbock, Te xas 40 Grain sorghum yields did not show a consistent pattern of ~esponse to the foliar application of Zn. Zinc depressed the 1ield at the 200 lb. P level; however, less depression in yield las observed at the higher Prates. In general, lower y ields iccurred with the foliar application of the ZN-Fe combination P.ither with or without P. Average yields were comparable be tween the two varieties with 5964 and 6177 lb. per acre with jK-280 and G-766W, res pectively . iummary A-P fertilizer study with foliar application of Fe and Zn was :onducted on Pullman sil ty clay loam with irrigated grai n sorghum. I . Maximum production was obtained with the application of 200 lb. of P 0~ per acre without trace elements. However, when Fe was ~pplied yields2 increased up to the 400 lb. level of P O per acre. ~pplicati o n of Fe consistently increased yields with ~o~t levels of P fe~tilization; however, Zn reduced yields when applied alone and In combination with Fe. Acknowledgment This study was partially supported by Diamond Shamrock Co., ~marillo; Northrup-King Seed Co., Richardson, Texas; Funk Brothers ~eed Co., Lubbock, Texas; and Geigy Chemical Co., Lubbock, Texa s. Thi s assistance is gratefully appreciated. Table 1. Yields of irrigated grain sorghum at four P levels with foliar application of trace minerals.

:Treatments Varieties Trace Elements NK-280* G-766W* lb. grain/acre lb. grain/acre

. 0 l No2e 5977 6232 Fe 6681 6363 Zn 6018 5833 Fe Zn 5117 5674 200 None 623 2 6744 Fe 6431 6408 Zn 5462 5925 Fe Zn 5918 574 5 400 None 5651 6581 Fe 6590 6818 Zn 6203 6480 Fe Zn 5438 6003 800 None 5953 6070 Fe 6408 652 2 Zn 5902 5971 Fe Zn 5139 5429 Average 5964 6177 2Pounds of P2o5 applied per acre as 0-46-0 Trace elements applied as a foliar spray (2 lb. /acre). *Northrup-King and Funk Bros. varieties, respectively. Men ti on of proprietary products does not necessarily imply endorse ment of these products over other comparable products. 41 YIELD AND CHEMICAL COMPOSITION OF IRRIGATED SORGHUM GRAINS PRODUCED ~ITH DIFFERENT NITROGEN FERTILIZATION LEVEL S

L. B. Sherrod and R. IL Furr* Introduction Sorghum grain production in the So uthwest has become increas ingly important as a so urce of feed grain for the rapidly expand ing feedlot industry. Improvements in productivity and feeding value of sorghum grain are necessary to keep pace with this in creased demand. These improvements are largely accomplished through development of new varieties and improved crop production practices. The study reported herein was conducted to evaluate yield, test weight, and chemical composition of two varietfes of sorghum grain produced under irrigation with four levels of nitro gen fertilization. Procedure Eight 0.7 acre plots with three equal replications within each plot were used in a 2 X 4 experiment involving two main treatments (varieties) and four subtreatments (nitrogen fertili zation levels) . The plots were located on uniform Pullman silty clay loam soi l having "A" slope and common previous treatment. Ea ch plot was ei ght 40-in.c h rows 1200 ft. long with three 400 ft. replications within each plot . The main treatments were a wa xy grain (3761) 1 and a nonwaxy grain (222A) 2 and the subtreatments un der each main treatment were 0, 60, 120 and 180 lb. nitrogen per acre . The seed bed was prepared by standard practices and bedded prior to planting. Nitrogen was applied at the respective l evels on the nitrogen treatment plots with a single preplant applicatiM of anhydrous ammonia, placed at a depth of 10 in. in 20 in. spacings in the sides of the furrow beds abo ut lD days prior to · planting . Both varieties were planted on May 21, 1968, at rates of 12 lb. per acre in 10 in. double rows on top of the furrow b~ Preplant herbicide meth ods were used for we ed co ntrol . Irrigatio rates were co ns tant on all plots with about four acre inches at each of three post plant irrigations. The middle four rows of each repl ication within the various plots were combine harvested to determine yield . Grain s amples were taken from each replication to determine test weight and composition of the grain produced under the respective treatment conditions. Proximate analysis were conducted by A.O.A.C. (1960) methods. Sulfur determinations were made by the barium chloride turbidity method (Warner, 1970). Al l other mineral elements were determined by atomic absorption spectrographic procedures (Warne~ 1970). Results !..!!i Discussi on Yield, test weight and composition of the two types of sorghum grain produced under the different nitrogen fertilization

*Present address: Hi-Pro Feeds, Inc., Friona, Texa s 1 2 • Funk Bros. and Northrup-King varieties, respectively. Mention of proprietarv products does not necessa rily imply endorsement of these products over other comparabl e products.

42 treatments are presented in table 1. Grain yields were improved fn both varieties with each higher level of nitrogen fertiliza tion . Ave r age yields were 5160 and 5745 lb. per acre with the -axy and nonwaxy grains, respectively. Results from the present !xperiment are consistent with those from other studies which \ave shown improvements in yield within varieties with increased levels of nitrogen fertilizer and variations in yield between jifferent sorghum grain varieties (Porter et !.l_., 1960; Eng, 1965; Robertso·n and Walker, 1966; Worker aiid Ruckman, 1968; Sherrod et al., 1969). Test weights were also increased in i·~oth var1et1es by application of nitrogen compared with the ·:ontrol grain. This increase in test weight occurred at each ;igher level with the nonwaxy grain and with each level up to 120 lb. per acre in the waxy grain with a slight decrease when ~itrogen application was increased from 120 to 180 lb. per acre. 1 ~verage test weight was higher for the nonwaxy (58.8 vs. 57.8) ~ompared with the waxy variety. ! Crude protein content increased in both varieties with each ~igher level of nitrogen ferti lization . Protein content was comparable between the two vari eties ~ith 9.6 and 9.1% for the ~axy and nonwaxy grains, respectively. The data r~ported herein !re in agreement with results reported by other investigators (Eng, 1965; Robertson and Walker, 1966; Sherrod et al., 1969) #ho found that protein content of s orghum grain Tii'creased with higher levels of nitrogen fertilization. Differences in protein content between the two varieties used in the present study ~ere less evident than has been reported in other varietial comparison studies (Eng, 1965; Worker and Ruckman, 1968). These comparative results lend further evidence that different sorghum grain varieties may vary considerably in crude protein co ntent. Levels of the other proximate components were generally compa rable between varieties and levels of nitrogen. The slight ~ecrease in nitrogen-free extract with each higher level of ~itrogen was reflected by the increased crude protein content. ~ine ra l levels were also generally similar between varieties with no major affect from nitrogen fertilization l evels. ~herrod et !}_., (1969) also found that mineral composition of jrrigate

~·O:A . C. 1960. Official Methods of Analysis (9th ed.). Asso ciation of Official Agricultural Chemists. Washington, o.c. . . Eng, K.S. 1965. Current and f uture research related to the fee~ing value of sorghum grain. Proceedings, Fourth Biennial Grain .Sorghum Producers Research and Utilization Conference (Amarillo, Texas) p. 29.

43 Table 1. Yie l d and Chemica l Composition of Irrigated Sorghum Grains Produced with Different Nitrogen Fertilization Levels

Type of sorghum grain Waxy No nwaxy Nitrogen level, lb. per acre D 60 1 20 180 0 60 1 20 180 Yield, lb. per acrea 4106.0 5203.0 5578.0 5755.0 4655.0 5845.0 5859.0 66 22. 0 Test wt .• lb. per bu. 56 . 0 57 . 7 59.0 58 . 3 58.0 58. 7 59.0 59.7 Composition, OM basis, % Crude protein 6.8 8.7 10.9 12. 1 6.4 8.2 10. 2 11. 7 Crude fat 3. 2 3.2 3.0 3. 1 3.0 2. 9 3. 1 3. 1 Crude fiber 3. 1 3.4 3.0 3. 1 2.8 2.7 2. 5 2. 1 As h 2. 1 1. 8 1. 8 1. 9 1. 6 1. 6 1. 6 1. 8 N-free extract 84.8 82.9 81. 0 79.6 86.2 84 . 6 82.6 81. 3 Calcium

45 SEWAGE EFFLUENT AS AN IRRIGATION RESOURCE L. B. Sherrod,* Dale Hollingsworth* and R. D. Furr** Introduction The volume of water from sewage effluent increases in proportion with population increases in urban and subu~ban developments. This increased concentration of populat1on puts increasing demands on use of existing water reserves. Sewage effluent from the metropo l itan area amounts to many millions of gallons of water daily, which could be made available for irrigation of agricultural crops. The use of sewage effluent for irrigation could also conserve existing ground water and prevent complete depletion of these water reserves. This study was initiated in 1967 to evaluate the use of sewage effluent for irrigation with the following objectives: 1. To compare the effect of sewage effl uent with well water on yield and quality of irrigated grain sorghum. 2. To evaluate the effect of nitrogen fertilizer on yield and quality of grain sorghum irrigated with sewage effluent and well water. Procedure The sewage effluent was obtained from two government instal· lations located near Amarillo, Texas. The well water was receivE from deep wells pumping out of the Ogallala formation. The study was conducted on Pullman silty clay loam soil having "A" slope with common previous treatment. A full season grain sorghum variety was planted in a split-plot experiment involving two main treatments and two sub-treatments replicated three times for a total of twelve plots. Each plot was eight 40-in. rows one-half mile long. The main treatments were sewage effluent and well water and the sub-treatments O and 185 lb. of nitrogen per acre. The seedbed was prepared by standard procedures and bedded prior to planting. Nitrogen was applied to the fertilized plots with a s ingle preplant application of anhydrous ammonia, banded on the sides of the furrow beds (20 in. between bands) at a depth of 10 in . The grain sorghum was planted (May 11, 1967, May 15, 1968 and May 24, 1969) at the rates of 10 lb. per acre in 10 in. double rows on top of the furrow beds. Herbicide was applied after planting for weed control . Irrigation rates were constant at four acre in. for each of three post- plant irriga tions with both sources of water. The middle four rows of ea ch plot were combine harvested to determine yield. Grain from each plot was sampled to evaluate test weight and composition of the grain sorghum produced under each treatment condition. Each sample was prepared and analyzed for ~he following nutrient components: nitrogen (crude protein), ~alc1um, phosphorus, magnesium, potassium, sulfur, manganese, iron, copper, zinc and molybdenum. Nitrogen was determined

*An im al Nutritionist and Assistant Agronomi s t, Texas Tech University Research Center, Pantex, Texas **Present Address: Hi-Pro Feed, Inc., Friona, Texas 46 using standard A.O.A.C . (1960) procedures. Sulfur determinations were made using the barium ch loride turbidity method (Wa rner , 1970). All other eleme nts were determined on a direct reading emission spectrograph (Warner, 1970). Samples of the sewage effluent were also obtained at periodic interval s for chemical analysis using similar procedures.

Results ~Discussion Yie ld and test weight data are given in table 1. Grain yield for the three year average was lowest for the unfertilized grain sorghum i rrigated with well water. Grain yields were higher when irrigated with sewage effluent compared with well water when both water sources were used without nitrogen fertilizer . Tab le 1. Yield and test weight of grain sorgh um irrigated with well water and sewage effluent with two levels of nitrogen fertilizer for crop year 1969, and fo r a three year average.

Water source Well water Sewage effluent Nitrogen 1eve1 , lb. per acre 0 185 0 185 1969 crop year Yield, 1 b. per acrea 3766 5117 3953 5266 Test wt., lb. per bushel 56.7 54.0 56. 3 53.8 Three year average Yield, 1 b. per acrea 4411 5863 4928 5956 Test wt. , 1 b. per bushel 56.5 55.7 56.9 55.9 aAdjusted to 88% dry matter. Application of 185 lb. nitrogen per a cre resulted in higher yields with both so urces of water. Grain sorghum yields for the 1968 (Sherrod et al, 1969) and 1969 (table 2) crop years on the un fertil izeO-pTOts were lower than the yields for 1967 (Sherrod et !.!_., 1968). The se results may have been ca us ed by the depletion of the available soil nitrogen, and by variations in the chemi cal composition of the sewage effl uent. Test weights tended to be slightly lower for the grain produced with 185 lb. nitrogen per acre both for the 1969 crop and the three year average. Composition of the grain sorghum produced under the differ ent treatment condi ti ons for the 1969 and the three year average i s presented i n table 2. Nitrogen fertilization tended to in crease crude protein level s in the grai n sorghum irrigated with bo t h s ewage effluent and we ll water i nc luding the 1969 crop and the three year average.

47 Table 2. Composition of Grain Sorghum Irrigated with Well Water and Sewage Effluent with and without Nitrogen

Water source Well water Sewage Effluent N. level, lb. per acre 0 185 0 185 1969 Crop year Composition , DM basis, % Cr ude protein 9.00 11. 88 7. 31 10. 1 2 Calcium

Levels of macrominera l s (those expressed in percent) and micro minerals (expressed in parts per million) were slightly increased with nitrogen fertilization with both water sources for the thre~ year c rop period (1967-1969). There was some variation in mineral composition between years which may reflect seasonal effect s on the growth of grain sorghum . The results reported herein (table 1) indicate that yields were improved by sewag e effluent compared with well water when both were used without nitrogen ferti 1 i zer, suggesting that sewage effluent had some fertilizer value. However, similar increases were not reflected in the compo s ition of the grain (table 2). The average composition of the sewage effluent used in this study over the t hree-year period expressed in parts per million was : nitrogen , 32.0; phosphorus, 7.2; potassium, 18.2; calcium, 67.l; magnesium, 30.0; s ilicon, 8.5 ; sodium, 10.2 ; manganese, 0.04; iron, 0.37; boron, 0.29; copper, 0.03; zinc, 0.06; - a·luminum , 0.14; and barium, 0.12. Based on this average composition, an acre-foot of the sewage effluent used in this study s upplied 87.0 lb. of nitrogen, 19.6 lb. of phosphorus, 49.5 lb . of potassium, 182.4 lb. of ca lci um, and 81.5 lb. of mag nesi um per acre plus the several minor elements whi ch were also present. Compo s ition and actual fer t i li zer va l ue of t he effluent varied considerably between yean with the highest values during the first year ( 196 7} . This varia· tion in composition was attributed to changes in the original 48 content of the effluent. Other investigators ( Day~ al ., 1962; Ha r vey and Cantrell, 1965) have reported various fertiTTzer values for sewage effl uent wh ich were dependent primarily upon the type · and so urce of the effluent. They also found that improvements in yield and composition of crops irrigated with effluent were directly related to the fertilizer value. The res ults of the pre- · sent t hree year study indicate that sewage eff luent contains a certain fertilizer value in addition to its water value. These results along with those of the other investigators further sugges t that this fertilizer value can vary considerably which , in turn, influences the relative improvement in yield and nutri ent composition of crops irrigated with the effluent. Summary Irrigation studies with grain sorghum were conducted over a three-year period to com pare two water sources (sewage effluent and well water) and two nitrogen fertilization levels (O and 185 lb . nitrogen per acre) upon yield, test weight and composition of the grain. Yields were improved by the sewage effluent compared with well water when both were used without additional nitrogen. Nitrogen ferti l ization resulted in higher yields with both sources of water. Test weights were generally similar for all treatments. Crude protein content was slightly lower with the grain sorghum produced with sewa ge effluent without fertil izer when compared to well water. Application of nitrogen fertil izer with both water sources improved the crude protein level of the grain sorghum. Mineral levels in the grain also tended to be improved with nitrogen fertilizer using both water sou r ces . These results indicate that sewage effluent i nc reased yields of irrigated grain sorghum with little or no effect on grai n composition sug ge sti ng that the fertilizer value of sewage effluent should be con sidered important in addition to the water value. Literature Cited A.O . A.C. 1960. Official Methods of Analysis (9th ed.). Asso ciation of Official Agricultural Chemists. Washington, D.C. Day , A.O. , T.C. Tucker and N.C. Vavich. 1962. Effect of city sewage effluent on the yield and quality of grain from barley, oats and wheat. Agron. J. 54:133. Harvey, C. and R. Cantrell . 1965. Us e of sewage effluent for producti on of agricultural crops. Te xas Water Dev . Board Rpt . 9.

Sherrod, L.B ., R. D. Furr and A. W. Young. 1968 . The effect of sewage effluent and nitrogen fertilization on the yield and c ompositi on of irrigated grain sorghum. Texas Tech. College !CASALS Sp. Rpt . No. 4 :1. Sherrod , L.B., R.D . Furr and A.W. Young. 1969 . Further Observations on the use of sewa ge effluent for irr iga t ing grai n sorghum. Te xas Tech University. !CASALS Sp . Rpt . No. 18 : 53. Warner, M.H . 1970. Personal communications. Ohio Agr. Re s. and Dev. Center, Wooster, Ohio. Acknowledgment

Appre ciati on is expressed to Harold Roberts fo r his cooper ation and assistance in making this study possible.

49 CONTROL OF FIEL~ BINDWEED AND BUR RA GWEED WITH SOI L STERILANTS Dwane E. Lavake, Dale Hollingsworth, A. F. Wie se , Wayne Chenault and Wendell Vandiver* Introduction Field bindweed and bur ragweed infest about 300,000 acres in the Panhandle area causing an estim ated seven mi llion dol lars worth of crop loss each year. In 1967 and 1968 soil steri lant trials were initiated to determine which s terilants were best suited for the eradication of these two perennial weeds. Procedure Plot size wa s either 10 ft. by 16. 5 ft. or 16.5 ft. Ea ch herbicide treatment was replicated three times. Steri l ants were applied in a water carrier at 35 to 40 psi i n 20 ga llons per acre. The back half of the 1967 bindweed soil sterilant trial was incorporated with a tandem di sk immediately following sterilant application. Results and Discussion Bindweed control data obtained from the October, 1967 t rial are found in table 1. With the exception of two experi mental herbicides , effective bindweed co ntrol resulted from some rate of the steri l ants utilized in the trial. Incorporation tended to decrease the toxicity of the herbicides. Thi s was especially true with U22-326. Results of soil sterilant trials applied to bur ragweed in 1967 and 1968 are found in tables 2 and 3. Effective co ntrol prevailed for 2 years on Tordon treated plots i n the 1967 trial i f at least 1 lb. per acre was applied. Results with Tordon was better t han with other herbicides. The sterilants employed in the 1968 trial effectively controlled bur ragweed. Excellent control was obtained on the Tordon treatments where an excess of 2 lb. per acre was applied. Tordon Bead s at 1 lb. per acre gave the best control fo r the least amount of herbicide applied. Summary One and two years following sterilant application, Tordon wa s effectively controlling bur ragweed and bindweed. Bur rag weed was harder to co ntro l with PBA, TBA, Tritac and Fenac than with Tordon.

*Technician, Texas A&M University, Agronomist , Texa s Tech Re search Farm, Professor and Tech nicians, Texas A&M University

50 Ta ble 1 . Fiel d bi ndweed control on 8-21-69 after application of he rbicides on 10-2-67.

Lb./ A Percent bindweed control Herbi cide ( ai) Not I ncoq~orated I n coq~orate d Average Che ck 0 0 0 i a PBA 40 95 75 85 d TBA 20 100 100 100 a Tri tac 20 100 100 100 a Fenac 20 93 93 93 abed To rd on 22K 1/2 86 30 58 f 1 67 8 37 g 2 99 83 91 abed 3 98 93 96 abc 4 100 95 97 ab Tordon 212 l /2 + 1 93 58 75 e (Tordon + 2,4-D) l + 2 92 85 88 cd 2 + 4 98 88 93 abed 3 + 6 99 99 99 a 4 + 8 99 99 99 a Tordon Beads l / 2 63 58 61 f l 99 97 98 a 2 100 96 98 a 3 100 100 100 a 4 100 100 100 a T0-4BO 20 100 97 98 a 40 98 98 98 a s 0- l 5179 5 0 0 0 10 0 0 0 i U22 - 326 10 0 0 0 i 20 50 0 25 h 40 83a 0 42 g Average 78 65b

aAverages fo ll owed by t he s ame l etter are not diffe rent. Table 2. Bur ragweed control 8- 18-69 after application of herbi ci des on 10-1-67.

Herbi cide Lb. /A {ai) Percen t bur ragweed control Check 0 g a PBA 40 63 de TBA 20 78 bed Tri tac 20 1 7 f Fena c 20 55 e Tordon 22K 1/2 91 abc 1 93 abc 2 88 abc 3 99 a 4 90 abc Tordon + 2 ,4-0 1/2 + 1 77 cd ( M- 306 1 ) 1 + 2 91 abc 2 + 4 92 abc 3 + 6 90 abc Tordon Beads 1/2 63 de 1 95 abc 2 96 ab 3 99 a 4 100 a a Data fol l owed by the s ame letter are not different. 51 Table 3. Bur ragweed control on 8-21-69 after application of herbicides on 9-11-68 .

Herbicide Lb. /A Percent bur ragweed control Check 0 ha PBA 32 85 ab 40 90 ab TBA 16 63 e 20 67 de Tritac 16 87 ab 20 85 ab Fenac 16 78 bed 20 87 ab Tordon 22K 1 /2 93 ab 1 79 bed 2 91 ab 3 98 a Tordon 212 1/2 + 1 83 abc (Tordon + 2, 4-D) 1 + 2 94 ab 2 + 4 98 a 3 + 6 92 ab Tordon 225 1/2 + 1/2 38 g (Tordon + 2,4,5-T) 1 + l 48 fg 2 + 2 97 a 3 + 3 93 ab M3348 1/2 + l 92 ab Tordon + 2,4-D ester l + 2 60 ef 2 + 4 93 ab 3 + 6 92 ab Tordon Beads 1/2 88 ab 1 99 a 2 100 a 3 100 a

aData followed by the same letter are not different.

52 WEED CONTROL STUDIES IN SORGHUM Wayne Chenault, Dale Hollingsworth, Allen F. Wiese, Dwane Lavake and Wendell Vandiver* Introduction In order that farmers may become more efficient, better con trol practices _for weeds in sorghum must be developed. With thi s 'objective in mind, several weed control studies were cond~~ted ·in 1969 at the Texas Tech Research Center. These include : (1) 'a preplant trial three weeks before planting, (2) a preplant trial !one day before planting, (3) a preemergence trial employing one :cultivation, (4) a preemergence screening trial and (5) an ·aerial application trial using various formulations of AAtrex and !,several oils for carriers to control pigweed and emerged sorghum. iEach s tudy will be discussed separately. ! !procedure, Results and Discussion ' ~- (1) Preelant study three weeks before planting : Several '. sorghum herb1c1des were apj)l'Ted""brOa~to weed-free beds with 1a ground rig on May 14, table 1. All plots were incorporated :with a rolling cultivator and Lindsey G-602 was planted on 6-3-69. !Existing weeds were destroyed before planting . Weed control data :taken on 7-8-69 show that Milogard and Igran resulted in the best -control and the least injury. AAtrex gave good weed control but ·some sorghum injury was observed.

: (2) Pre~lant ~~~before plantin~: In this trial, .table 2, her icides were appTfed to weed-freeeds with a ground 'rig on June 2 and one-half of each plot was incorporated 1immediately with a rolling cultivator one day before planting •Lindsey G-602 sorghum. Weed control data wa s taken on July 8. ;Igran and AAtrex resulted in excellent pigweed control when in ~orporated. Weed control, regardless of the herbicide, was \significantly better when the he r bicides were i ncorporated. '.There wa s no apprec iable sorghum injury. Weed control was better .than on the previous trial where herbicides were applied about three weeks before planti ng.

(3) Preemergence trial followed~ one cu ltivation: The herbicides and methods ~pp l icat i o n 1n-ulis trial were the Jame as in the preceeding preplant trials. Lindsey G- 602, a mid-season variety, wa s planted on 6-3-69. The herbicides were ~pplied on 6-5-69. Weed co ntrol data were taken on July 8 and are shown in table 3. Cultivation was accomplished with a rotary hoe on June 20. On July 8 no significant difference between the cultivated and noncultivat ed plots wa s observed. All the herbicides resulted ~n . good co ntrol. Milogard resulted in the least injury. The lnJury of t he other herbi cides ranged from 20% to 40 % whether cultivated or not. Weed contro l was somewhat better than wh ere prep lant applications were made.

*Technician, Texas A&M University, Bushland, Agronomist, Texa s Tech Research Farm, Pantex , Professor and Technicians, Texa s A&M University , Bushland 53 (4) Preemer~ence screening trial: A preemergence screening trial involv1ng2 herbicides was-TiiTtiated on June 6, three days after planting . The plots were two, 40-in. rows, 30 ft . long. Data was taken on July 8, as shown in table 4. The best control with the least injury resulted from the use of ACO-lSM, BAS-2903H, Milogard, Milogard + Lorox , Igran, LOP-64, Herban + Milogard, Milogard + Igran, GS-18182, GS-13529, Lorox, and HOE 2990. Injury was less than where herbicides were applied two days later .

(5) Aerial ap~lications of AAtrex: On June 27, an aerial trial was--concfiicte employing-Various formulations of AAtrex and several oils as carriers. The best weed control was obtained with 2 lb ./gal. Sun invert emulsion formulation and the 80% WP, (wettable powder), table 5. Enough Sun llE oil was added to provide the carrier for the invert emulsion. The 80% WP with oil emulsion carrier resulted in control as good as with the liquid formulations with 011 emulsion carrier. Summary Results in three preplant trials indicate preplant treatmenh are feasible for sorghum; however, at the present time no herbi cides are labeled. Milogard may be labeled in 1970. Incorporati~ was necessary for best results. When using preplant herbicides, sorghum must be planted on top of the beds or herbicides will be moved away from the crop row and into the middles. In a preemergence trial, cultivation did not improve the quality of weed control. ACD-15M, BAS-2903H , Milogard, Igran, LOP 64, Herban + Milogard, Milogard + Lorox, Milogard + Igran, GS-18182, GS-13529, Lorox, and HOE 2990 gave good weed control. Igran, LOP 64, Prolin, Herban + Milogard, and Mil99ard + Lorox are short soil residual herbicides which may be useful in crop rotations with crops that are sensitive to Milogard residues in the soil. The aerial trial using various formulations of AAtrex indicates that aerial application of AAtrex is feasible and that an invert emulsion formulation is slightly better than the 80% WP formulation.

54 Table 1. Percent pigweed control and sorghum injury on 7-8-69 fo llowing a preplant (before irrigationa) application of herbicides on 5-14-69.

Broadcast Percent Percent Herbicide Lb ./A (ai) pigweed control sorgh um injury Milogard 1 89 a-cb 0 b 2 93 a 0 b AAtre x 1 87 a-d 15 a 2 87 a-d 14 a Herban + Milogard 1 + 1 /2 81 cd 0 b 2 + 1 78 d 0 b Lorox + Mil oga rd 1/2 + 1/2 77 d 0 b 1 + 1 82 b-d 0 b I gran 2 93 a 0 b 4 92 ab 5 b Check 0 0 e 0 b . Plot size four, 40-inch rows, 50 ft. long. Broadcast '. application. Incorporation wa s accomplished with a ro l l ing cultivator. aA pp lied before preplant irrigation. Within 30 days foll ow :ing appli cation, 2.23 in. of rainfall was recei ved, eliminating the need for irrigat ion. Replicated six times. ba-c = abc etc ... Data followed by the same letter are not di fferent .

Table 2. Percent pigweed control and so rghum in~ury on 7-8-69 following a preplant (after irrigation ) application of herbicides on 6-2-69.

Percent Percent Broadcas t eigweed control sorghum inj ury Herbic ide Lb. /A (a i ) Inc. Not. Avg . In c. Not. Avg. j·Mi logard 1 97 88 92abb 5 0 3 b-d 2 99 85 92ab 1 3 5 9 a :AAt rex 1 1 00 89 94a 5 3 4 a-d t 2 98 80 89a-c 1 3 0 6 a - c !Herban + Mil ogard 1 + 1/2 98 79 89a-c 8 3 5 a-d 2 + 1 98 73 85b-c 0 3 1 cd jl orox + Milogard 1/2 + 1/2 98 80 89a-c 3 0 1 cd ' 1 + 1 99 80 90a -c 3 0 1 Cd ;Igran 2 100 88 94a 13 3 8 ab 4 99 68 83c 5 0 3 b-d !check 0 0 0 Od 0 0 0 d '. Average 89a 73 b 6a 1 b Pl ot size four, 40-in. rows, 50 ft . long. Broadcast .application. Incorporation accomplished with a rolling cultivator. aApplied on 6- 2-69 after irrigation. With i n 20 days prior t o application 0.76 in . of rai nfall was received eliminating the need for irrigation. b a-c = abc etc . .. Data followed by the same letter are not :different .

55 Table 3. Percent pigweed control and sorghum injury on 7-8-69 following a preemergence application of herbicides on 6-5-69. Percent Percent pigweed control sorghum injury Broadcast Not Not Herbicide Lb./A (ai) Cult. Cult. Avg. Cult. Cult. Ava; Mil oga rd 1 99 97 98aa 13 13 l 3d 2 99 97 98a 15 1 3 14d AAtrex 1 100 99 99a 20 15 l Scd 2 100 100 lOOa 38 43 40a Herban + Milogard 1 + 1/2 100 94 97a 20 28 24bc 2 + 1 99 99 99a 20 38 29b Lorox + Milogard 1/2 +l/2 100 94 97a 30 20 25bc 1 + 1 100 100 lOOa 20 33 26bc I gra n 2 100 100 lOOa 25 28 26bc 4 100 99 99a 38 40 39a Check 0 0 Ob 0 0 Oe Average 90a 89b 2 2a 24a Plot size= four, 40-in. rows, 50 ft. long. Three replicatioc Cultivated once on 6-20-69 with rotary hoe. Planted Lindsey G-602 on 6-3-69. aa-c=abc etc ... Data followed by the same letter are not different. Table 4. Percent pigweed control and sorghum inJury on 7-8-69 following a preemergence application of herbicides on 6-3-69a.

Percent Percent Herbicide Lb./A (ai) pigweed control sorghum injury ACD-15M 1 3 x-y 0 j 2 89 a-ib 1 7 d-j 4 87 a-j 8 h-j BAS-2903 H 1 3 x-y 7 i -j 2 57 p-s 7 i-j 4 85 a-k 10 g-j Coto ran 1 13 w-y 7 i -j 2 70 j-p 32 cd 4 91 a-h 67 b Cotoran + Milogard 1/2 + 1/2 74 g-o 8 h-j 1 + 1 81 c-m 18 d-i 1/2 + l 1/2 95 a-e 25 c-h l + 2 92 a-g 37 c Cotoran + Maloran 1 + 2 98 a-d 28 c-f Milogard 1 93 a-f 10 g-j 2 98 a-d 12 f-j I gran 1 92 a-g 3 i-j 2 94 a-f 7 i-j 3 99 ab 3 i -j Milogard + Igran 1/2 + 1/2 48 r-u 0 j l /2 + l 86 a-k 3 i -j 1/2 + 2 96 a-e 12 f-j 1 + l 97 a-d 13 f-j Milogard + Lorox 1/2 + 1/2 86 a-k 3 i-j 3/4 + 3/4 92 a-g 0 j 1 + 1 84 a-1 5 i-j LOP-64 1/2 + 1/2 88 a-j 18 d-i 3/4 + 3/4 85 a-k 13 f-j 1 + 1 94 a-f 3 i-j - continued - 56 Table 4. continued

Percent Percent Herbicide Lb./A (ai) pigweed control sorghum injury Prolin 1/2 + 1/2 89 a-i 5 i -j 3/4 + 3/4 95 a-e 32 cd 1 + 1 98 a-c 27 c-g Check I O 0 y 0 j Herban + Milogard 1/2 + 1/2 68 k-p 18 d-i 3/4 + 3/4 85 a-k 10 g-j 1 + 1 89 a-i 10 g-j Herban + Milogard 2/3 + 1/3 79 e-n 3 i-j 1 + l /2 82 b-1 17 d-j 1/3 + 2/3 95 a-e 2 i -j 2 + 1 90 a-h 1 3 f-j GS-18182 1 67 1-q 10 g-j 2 82 b-1 0 j 4 95 a-e 7 i-j GS-13529 1 97 a-d 8 h-j 2 100 a 3 i -j 4 l 00 a 15 e- j GS-53619 2 93 a-f l 3 f-j 4 98 a-d 30 c-e Lorox 1 73 h-p 2 i -j 2 93 a-f 17 d-j HOE-2990 1 27 v-w 0 j 2 63 n-r 0 j 4 90 a-h 10 g-j R-1191 3 2 86 a-j l 3 f-j 2 l / 2 88 a-j 1 3 f-j 3 77 f-n 8 h-j R-15431 2 78 e-n l 3 f-j 4 80 d-n 5 i -j R-16024 4 47 s-u 0 j 6 70 j-p 7 i -j Check II 0 0 y 0 j RP-17623 1 93 a-f 62 b 2 99 ab 83 a VCS-437 2 8 xy 3 i -j 3 33 UV 0 j 4 0 y 0 j Herb an 1 17 wx 3 i -j 1 l /2 50 r-t 3 i-j 2 0 y 0 j Londax ( Lorox + Ramrod) 3/4 + l /2 72 i -p 5 i -j 1/2 + 1 33 UV 0 j 3 + 2 7 2 i -p 17 d-j SD-17115 1 40 t-v 3 i-j 2 57 p-s 0 j 4 58 o-s 7 i -j Check I II 0 0 0 Plot size= two, 40 in . rows, 30 ft. long. Sprayed at 35 psi and 40 gpa . Three replications. Planted Lindsey G-602 on 6-3-69. aRainfal l, 6-3-69 - Date sprayed 6- l 3- 6 9 - 1 . 7 3 6-16-69 - .17 6-19-69 - .72 7-5-69 - 1. 88 7-8-69 - Data taken Total - 4. 50 b . a-1 = a ,b ,c,d,e,f,g,h ,i . Data followed by the same letter are not different . 57 Table 5. Percent pigweed control on 7-9-69 following aerial application of AAtrex on 6-27-69 .

AAtrex Percent Formula ti on Oil Lb./A (ai) GPA pi gweed control 4 lb./gal. liquid Sun llE l l/2b 85 Sun llE 2 l 87 2 lb . /gal . liquid Sun l lE l l/2c 59 Sun llE 2 86 80% WPa Sun llE l ~d 90 Sun 11 E 2 2 95 80% WP Orchex DX-70 l le 83* 80% WP Orchex DX-15 l lf 69* 2 lb./gal. Sun invert Sun llE lg 98* *Average of six observations in one replication. Others are on average of 12 observations in two replications. aWettable powder. bl to l ratio of liquid AAtrex to Sun llE, no water. cliquid AAtrex, no oil or water. dl to 3 ratio of Sun llE to water. el to 3 ratio of Orchex DX-70 to water. fl to 3 ratio of Orchex DX-15 to water. 91 to ratio of liquid Sun invert to Sun llE, no water .

58 A TECHNIQUE STUDY OF SEEDING ABANDONED CROPLAND TO RANGE GRASSES* Dale Hollingsworth and Joe Schuster** Introduction Vast acreages of abandoned cropland in the Great Plains are currently producing only a fraction of their potential. A r ecent review of conservation needs (S.C.S. Rpt. 1956) revealed that more than 6 million acres now in cultivation on the Great Plains area. should be seeded to perennial grasses to reduce erosion losses. Also, excessi ve grazing and periodic droughts have so damaged the virgin cover in some range areas that revegetation is desirable. Several methods have been used, with varying success, to seed abandoned fields. Though interseeding is highly regarded, the stubble-mulch and the cultivated methods have been most reliable in this region . In the spring of 1969 a study was initiated at the Texas Tech University Research Center to compare the effectiveness of culti vated seedbed versus the stubble-mulch seedbed method. Other objectives were to (1) compare emergence and establishment of commercial and Loveington blue grama (Bouteloua gracilis), and (2) to compare emergence and establishment of sideoats grama (Bouteloua curtipendula) to blue grama grass. Procedure The 196B range interseeding study on the Te xas Tech Univers ity Center was considered a failure due to an unproper seed unit con figuration for use in moist heavy soils (by creating a scalloped shaped furrow) and to high intensity rainfall that caused the grass seed to spoil. Optimum seeding establishment in the culti vation seeding method was satisfactory in the 1968 study with approximately three times as many blue grama and sideoats grama Plants emerging compared to the interseeded plots (Herndon, 1969) . The 1968 cu l tivation seedbed method of grass seeding wa s re fined and repeated on the randomly located interseeded experimental plots during the spring of 1969. This seeding method consisted of the use of one disking with a heavy duty off-set disk to undercut the heavy forb growth followed by two tillages with a mulch tiller. The mulch tiller (screw tredder) was used to form a protective mulch and to control the Kochia (Koc hia scoparia) weed }rowth. Grain sorghum s tubble established the previous year was used is the dead litter cover for the stubble mulch seedbed method. rhe grain sorghum stubble was deep chiseled to aid in moi s ture penetration, followed by two tillages wi th a mulch tiller to con trol the early weed growth . Control plots were left unplanted for future compari son.

*Thi s study wa s supported by the U.S. O. A. Soil Conservation Service and U.S.O.A. - A.R.S. - A.E., Southwestern Great Plains Research Center, Bu s hland , Te xas. **Assistant Agro no mist, Te xas Tech University Research Center, Pantex, Texa s. Professor of Range Management, Texas Tech University, Lubboc k, Te xas .

59 A rangeland drill with heavy packer wheels spaced on 12-in. row centers was used to seed the plots. The grasses planted were the commercial variety of blue grama and the El Reno variety of sideoats grama. Two of the plots were planted to Loveington blue grama for the blue grama variety comparison. For each method, the planting depth was 1/2 in. with a planting rate of approximately 4 lb. of pure live seed per acre. Seeding dates were May 16-28 with no appreciable moisture received until mid-June. Herbicides were applied to control annual forbs when the grass seedlings had reach· ed the three leaf stage. Results and Discussion Summer plant counts showed no significant differences in blue grama emergence by both seeding techniques. Five times the amount of Loveington blue grama plants emerged when compared to the com mercial blue grama in both seeding studies (table 1). Similarly, seeding establishment was over five times as great. These results indicate that Loveington blue grama might improve the chances for range revegetation where a blue grama range is desired. Sideoats grama seedling performance was less than the blue grama seedling; however, plant establishment was satisfactory. Herbicides applied at the three leaf stage was effective in controlling annual forbs without any noticeable damage to the three varieties of grasses. Late summer observations determined that the grasses had produced satisfactory plant growth for an established stand. Table 1. Emergence Data Blue grama Si deoats Loveington Commercial El Reno Total plant count 1788 725 1196 ( 60 frames) (120 frames) (240 framr - x 29.8 6.04 4. 98" Summary Previous studies at the Texas Tech University Research Center have shown that the cultivated and stubble mulch seedbed method have been a reliable means to seed abandoned croplands. The results indicate that there was no significant differences in blue grama emergence when compared in both seeding techniques. Chances for a successful seeding may be improved by the use of Loveington blue grama with either the cultivated or stubble mulch seedbed method. Herbicides were effective in controlling annual forb growth in sma ll grass seedling without harming the plant success ional stage. The cultivated and stubble mulch methods are costly; however, the more costly, successful cultivation and stubble mulch methods may result in greater potential economic benefit. Literature Cited U.S.D.A. - Soil Conservation Service, Conservation Needs Rpt. 1956 . Herndon, E.B., D. Holli ngsworth, and J.L. Schuster. Seeding abandoned cropland on the Texas High Plains. 1969. Texas Tech College !CASALS Sp. Rpt. No. 18. Acknowledgment This study was partially supported by Geo. Warner Seed Co., Hereford, Texas and Tri-State Equipment Co., Canyon, Texas. This assistance is gratefully appreciated. 60 THE EFFECTS OF BURNING AND FERTILIZATION ON PRODUCTION AND UTILIZATION OF WEEPING LOVEGRASS W. Ellis Klett, Dale Hollingsworth and J. L. Schuster* This study was conducted to determine the effects of burning and fertilization on production and utilization of weeping love grass (Eragrostis curvula Schrad, Nees.). Weeping lovegrass has been seeded extensively throughout the southern United States since its initial introduction in 1927 from Tanganyika, East Africa (Hoover et al . , 1958). It is readily adapted to a wide range of climate and soils, especially on sandy soils of the south west . Weeping lovegrass has gained popularity as a fast maturing, high producin9 grass that can withstand extended drought periods (Staten, 1952). Its ability to S!Jrvive high summer temperatures and winter temperatures as low as -11° F. has led to its use as an erosion control grass (Staten, 1952) .

Weeping lovegrass grows quickly, and if planted in April, can be grazed about the first of the following July (Staten, 1952). Although a warm season grass, seed can mature as early as June and growth generally subsides with hot weather. Palatability is its weakest point. Grazed readily by cattle during the early growth period, its palatability drops off sha~ply as it reaches maturity. Spring controlled burning can improve early forage quality and increase forage production (Dalrymple, 1968). Study Area and Procedures An established 14 acre weeping lovegrass stand planted in May 1967 on the Texas Tech University Research Farm 14 miles east of Amarillo was used for the study. The vegetation consisted primari ly of seeded weeping lovegrass, although Kochia (Kochia scoparia), Johnson grass (Sorghum halespense), and silver bluestem (Andro~ogon saccharoides) were present in small amounts. The soil is a Pu lman silty clay loam, the major soil of the deep hardland sites in this region (Mathers, 1953). The climate is typical of the High Plains, with high summer and low winter temperatures. Precipitation aver ages 19 in., coming mostly during the spring and fall. Desiccating winds occur year round and commonly reach velocities of 35 mph. The study area was divided into four plots. Two plots were burned on January 2, 1969. One plot each in the burned and un burned areas received 44 lb. of nitrogen per acre by applying 200 lb. of bulk ammonium sulfate. Fertilizer cost was $5.60 per acre. The plots were grazed from May 27 to June 9 with five heifers and one bull. To determine herbage yield and utilization, ten randonly ~ ocated, paired, caged and uncaged 4.8 sq. ft. plots were clipped in each of the four treatments. Crude protein was determined by the Kjeldahl method.

Results ~ Discussion

Forage Production ~Nitrogen fertilization did not signifi cantly increase production (table 1). An inconsistent growth pattern contributed to this behavior. The weeping lovegrass made

*Research Assistant, Agronomist , Te xas Tech Research Center, and Professor of Range Management, Te xas Tech University. 61 some growth duri ng April, but growth tapered off rapi dly before rai ns in May relieved dry soil conditions. The fertilizer appeared to have had detrime nta 1 effects on the weeping 1 ovegrass during t he early dry peri od. A noticeable cessation in growth and a marked deterioration of the new growth was observed on May 2. This effect was more evident on the fertilized pl ots. Table 1. Pounds of oven-dry forage of weeping lovegrass and utilization under various treatments.l

Lb. I Ac % Crude Protein % Utilization Control 2068 3.6 10.7 Unburned-fertilized 2040 5.0 5.0 Burned-unfertilized 2380 7. 5 59.4 Burned-fertilized 2392 10. 5 62. 3 Production from January 2, 1969, to June 10, 1969. Utiliza tion measured after May 27 to June 9 grazing period by five heifers and one bull. Herbage production was significantly higher (14%) on the burn· ed plots . Burned plots averaged 332 lb. more forage per acre than unburned plots (table 1). These production figures represent growth only for the period January 2, 1969, to June 10, 1969 yet production surpassed that of previous studies in this area (Whitefield, Jones, and Baker, 1949). Utilization - Nitrogen fertilization had no influence on gra z· ing prefer ence on either burned or unburned areas, but burning greatly increased uti l ization (table 1). At the end of the 14 day grazing period , the cattle had grazed 62% of the burned weeping l ovegrass, but only 8% of the unburned. The lush green growth fr~ of dead carry· over growth on the burned area contributed to this difference. Higher protein content of regrowth on the burned area could also be a factor. Crude Protein Content - Composite samples from the untreated co ntalriTiiQ 81% carry over growth and 19% current season growth yielded 3.6% crude protein (table 1). Similar samples from the fertilized- unb urned plot contained 5.0% crude protein - an increase of 1.4%. Crude protein for the green material and carry over growth on the untreated control plot averaged 5. 7% and 2.9%, respectively. The regrowth on the burned areas had significantly hi gher amounts of crude protein. Samples from t he burned and fertilized plot averaged 10.5% crude protein and the burned-unfertilized plot yielded 7.5% crude protein. In other studies, Whitefiel d et al . ( 1949) reported crude protein for untreated weeping lovegrass~t 6.3% while Dalrymp l e (1968) recorded 19.7% crude protein on spring burned and fertilized plots and 11 . 8% on unburned- fertilized plots. Results seemed to indicate that the low crude protein content of the old carry over growth influences perference. Although new growth is available in the bunches, it is difficult for livestock to graze . Therefore, cattle tend to l eave the entire plant un grazed. The ability of weeping l ovegrass to "green up" during the winter with adequate soil moisture and warm temperatures is of little va l ue unless the carry over growth i s first removed. Burn· ing appears to be one method of doing this, but other methods s uch as mowing should be studied. Summary Burning increases the production and cattl e perference of weeping lovegrass. A wi nter burn increases spring and summer herb age yields of weeping lovegrass 14% and utilization 53%. Crude protein content was 3.4% higher on burned than unburned pl ots. Nitrogen fertilization increased crude protein but had little effect on forage production or utilization . Literature Cited

Dalrymple, R. L. 1968. Weeping lovegrass management. Noble Foundation Publication, Ardmore, Oklahoma. 39p.

Hoover, M. M. , M. A. Hein, W. A. Dayton and C. 0. Erlanson. 1948. Grass: Yearbook of Agri cul tu re. U. S. Government Print ing Office . 892pp. Mathers, Aubra C. 1963 . Some morphological, physical, chemica l, and mineralogical properties of seven Southern Great Plains soils. U.S . D. A., A. R. S. (Series) 41 - 85. 63pp. Staten, H. W. 1952. Grasses and grassland farming. The Devin-Adair Co., New York. p. 264-269.

Whitefield, C. J ., J. H. Jones and J. P. Baker. 1949. Grazi ng studies on the Amarillo Conservation Experiment Station. Texas Agr. Exp . Sta. Bull. 717. 2lp.

63 ADAPTATION AND YIELDS OF SEVERAL COOL SEASON GRASSES J. L. Schuster and Ricardo deLeon Good cool season grasses are scarce on the Southern High Plains. The primary reason for the lack of native cool season grasses is the prolonged dry winters that are not conducive to winter growth. The increase in cattle numbers in conjunction with growing feedlot industry further emphasizes the need for more green forage for stocker operations. Grain sorghum stubble and wheat grazing take pressure off of the native warm season pastures. Yet green forage is needed from the time livestock are normally removed from wheat fields in April until summer ranges are ready for grazing. Cool season grasses can fill this need but only one perennial s pecies, Western wheatgrass (Agrop~ron smethis), is native to the Southern High Plains. It survives under dryland condition, but production is limited and it characteristically makes up only a smal l portion of the native range plant composition. Previous introductions of introduced species under dryland conditions have not been successful in the Amarillo area {White field et al., 1949) . There are no records, however, of irrigated cool season grass trials. Because of the increasing demand for early spring grazing irrigated cool season pastures appear feasible. A cool season grass nursery was established on the Tech Research Farm in 1966 in cooperation with the Soil Conservation Service. Thirteen varieties of promising cool season grasses were planted under irrigation and studied for seedling vigor and establishment (Schuster, 1968). During the 1968-69 winter growing season these grasses were studied for herbage yield under irri gation and dryland conditions. Procedure The thirteen varieties of cool season grasses were well established in eight replications of four thirty foot rows of each species (Table 1). All grasses were mowed to a 4-in. stubble height in August 1968. Sixty pounds of nitrogen fertilizer was app l ied in August and 60 lbs. in March 1969 . Fo ur replications were kept irrigated to optimum moisture conditions throughout t he study . Three replications received no supplemental water. Data col l ection consisted of phenological observations at monthly intervals and two month l y clipping treatments. All species in all replications were sampled for forage production by clipping one 2.9 ft. permanently l ocated sample per replication at monthly intervals. Clipping height for each species was based upon estimated proper height of clipping . Six of the species were sampled more intensively and at two heights of forage removal, proper and heavy. This phase of the study was limited also to the irrigated replications . Table l shows the species and clipping heights. Clippi ng was beg un September 1968 and continued at monthly intervals through July, 1969. Composite samples were taken of the six intensely studied species for protein analysis.

64 Table 1. Species and varieties of cool season grasses tested, and their clipping heights used i n the experiment.

Proper Heavy No. Strain Common name Scientific nam e use use lnC es 1. A-12496 Intermediate Agropyron wheatgrass intermedium 6 3 2. Large Tall wheatgrass Agropyron elongatum 7 4 3. Sandia Orchardgrass Oactylis gl omerata 5 4. A-11701 Pubescent Agropyron wheatgrass trichophorum 5 5. Amur Intermediate Agropyron wheatgrass intermedium 6 6. Alkar Ta l l wheatgrass Agropyron elongatum 7 4 7. Jose Ta 11 wheatgrass Agropyron elongatum 7 4 8 . . Luna Pubescent Agropyron wheatgrass trichophorum 5 3 9. A-1488-MC Pubescent Agropyron wheatgrass trichophorum 5 10. NM-384 Tall fescue Festuca arundinacea 5 11. Western Agropyron wheatgrass smithii 4 2 12. Orchardgrass Oactylis glomerata 5 13 . Canada wi l drye Elymus canadensis 5 14. McGregor Hardinggrass Phalaris tuberosa 5

The heights of utilization are in accordance with recommend ations from technicians' guides of the Soil Conservation Service, USDA. 2 Species which appear with two values (proper and heavy) are the six grasses used in the intensive study of proper utilizati on.

~and Discuss ion Compa rison of Six Se lected Varieties Average forage yields for the intensely studied species ranged from 962 lb./ac for Western wheatgrass to 6387 lb. /ac f or Tal l wheatgrass (table 2). Table 2. Total oven-dry forage production (lb./acre) of six cool season grasses under three clipping treatments, 1968-69. 1

Monthly cutting Yearly cutting Proper level He avy level Proper level large tall wheatgrass 4944a 4370abc 6387a Jose tal 1 wheatgrass 4229ab 508 la 6047a Alk ar tall wheatgrass 4434ab 4984ab 5667a Luna pubescent wheatgrass 3683ab 3802bc 27 10b A-12496 intermediate wheatgrass3353b 3394c 3747b Western wheatgrass 1394c 1 550d 962c

For each co lumn mean yield data followed by the same letter are statistically similar at the .05 level of probability.

65 The three varieties of tall wheatgrass consistently yielded the most f orage. Medium yieldi ng species were Lu na pubescent wheat grass and A-12496 intermediate wheatgrass. Western wheatgrass was consistently the lowest producer. All varieties of tall wheatgrass and A-12496 intermediate wheatgrass produced more herbage when clipped only once at the end of the season than when herbage was removed monthly. This was ob served at both levels of c lipping. Protein content of these six varieties was slightly higher in plants clipped at the heavy use level than at the proper use level (table 3). Annual clipping resulted in s ignificantly lower pro tein production than that produced with monthly clippings . Protein content reached a maximum in all species during the most active vegetative growth period in April and was lowest at or just after the end of the flowering period in June. Table 3. Annual totals of protein production in lb./acre for each treatment on six species.

Proper Heavy use use Control A-12496 intermediate wheatgrass 649 669 323 Largo tall wheatgrass 870 805 544 Alkar tall wheatgrass 823 1009 456 Jose tall wheatgrass 788 1043 588 Luna pube scent wheatgrass 683 730 272 Western wheatgrass 266 281 110 Totals 4082 45"39 2296

Comparison of All Thirteen Varieties All 13 varieties were studied under irrigated and dryland conditions by clipping at the proper use level only at monthly intervals. Permanent plots were clipped at monthly intervals and the accumulated production was compared with prod uction obtained from one clipping at the end of the season. NM-384 tall fescue, both varieties of orchardgrass an d all varieties of Tall wheatgrass produced the most forage under both irrigated and dryland conditions (table 4). Ca nada wildrye and Western wheatgrass, both native species, were consistently the poorest producers under both dryland and irrigation. Phenology Observations All varieties of the same species had more or less similar growth and development patterns . Most active growth periods were from August to December and from March to July. Onl y Western wheatgrass stopped growth completely during the winter. This may be why this native species is able to survive dry winters under dryland conditions. Both strains of orchardgrass and NM-384 tall fesc ue flowered twice; once in the fall and once at the end of spring growth. The se species also drop t heir seed as soon as they mature. This could cause difficulty in seed harvest of these species.

66 The tall wheatgrasses were found invading other species by seed ling establishment and it is believed that this species has the best ability to establish and maintain itself of all species tested. The Largo variety is more leafy and appears more palatable than the other tall wheatgrass varieties . Table 4. Total annual yields in lb./acre for the 13 species under irrigation and dfyland, in both monthly and annual herbage removal.

Irrigated Dry land proper use proper use

~12496 intermediate wheatgrass 3055e 946cd Largo ta 11 whea tg ra s s 480lb 2013cd Sandia orchardgrass 6224a 2253a ~1170 pubescent wheatgrass 3854cde 1127bcd Am ur intermediate wheatgrass 3747de 1120bcd Alkar tall wheatgrass 4236bcd 17Blabc Jose tall wheatgrass 4158bcd 1640abc Luna pubescent wheatgras s 3687de 1330bcd A-1488 MC pubescent wheatgrass 3613de 1085bcd NH-384 tall fescue 6236a 2397a Western wheatgrass l397f 58 1d Orchardgrass 4706bc 1339bcd Canada wi ldrye 854f BB3cd

Species data in each co lum ~ followed by the same letter are statistically similar at the .05 level. Conclusions Based only on information for one year orchardgrass, the tall wheatgrasses, and NM- 384 tall fescue warrant further studies. They are productive, adapted to the climatic conditions under irrigation, and produce forage whe n it is needed in the Southern High Plains. They should fit well into an intensive grazing system which uses summer native range, crop res idues and winter wheat in rotation. They sh ould be able to provide adequate forage in the fall and spring months. Literature Cited

Schuster, J. L. 1968. Cool and Warm season grass trials at the Texas Technological College research farm. Texas Tech Re search Farm Reports pp. 38. Whitefield, C. J., J. H. Jones, and J.P. Baker. 1949. Grazing studies on the Amarillo Conservation Experimental Station 1943-49 , Texas A & M System Bull. No. 717, 21 p.

67 HERBAGE YIELDS AND UTILIZATION OF PLAYA LAKES ON THE TEXAS TE CH UNIVERSITY RESEARCH CENTER J. L. Schuster and Ricardo C. deLeon* Contribution of big playa lakes to cattle production in the Southern High Plains is substantial. These natural depressions receive runoff water from surround ing slopes. This increases moisture available for vegetative growth and allows more mesic and productive vegetative growth than on surrounding grassland sites. Observations indicate that cattle utilize vegetation in lake bottoms in preference to surrounding shortgrass vegetation during the April through July period. This study was initiated to determine the kinds of plants most commonly found on big, dry playa lakes; their biomass production, during spring and summer months; and the use livestock make of the forage. Procedure The playa studied, called "Big Playa", is located i n pasture 20 (Big Lake pasture) on the Texas Tech University Research Center. The pasture contains 472 acres of rangeland. The playa bottom covers approximately 150 acres . The surrounding drainage area is native shortgrass prairie dominated by blue grama (Bouteloua gracilis) and buffalograss (Buchloe dactyloides). The vegetation was studied by clipping all growth from 4.8 sq. ft . plots at the end of the grazing period in lg68 and 1969. Thirty-two plots on the lake bottom and 12 pl ots on the adjacent slope were caged to prevent grazing. These were paired with plots left to open grazing. The pasture was grazed 70 animal unit months (AUM) from May 16 to July 14, 1968, and 160 AUM from February 17 to Augu~t 15, 1969. The cattle used were cows with calves and a bull. Upon removal of the cattle, the paired plots were clipped and weight production determined for each species . Differences in weights between caged and uncaged plots were used for determination of utilization. Results Spi ne-bursage and l arge- spike spikesedge were by far the most abundant and productive plants in the bottom of the playa in 1968 whereas s l imleaf goosefoot and kochia were in 19 69 (table 1). These species also received most of the grazing as indicated by the utilization data. Differences between 1968 and 1969 in production and composi tion are attributed to differing climatic condi tions. Rainfall in early 1969 wa s very light and production wa s primarily annuals. Production and utilization data was collected i n mid July. Late July and August rains brought about more growth which was not measured.

*Professor of Range Management and Re search Assistant at Texas Tech University. 68 Table 1. Production and utilization of the species on the Big Playa Lake bottom on the Texas Tech Research Center, 1968 and 1969.

l.b.....L.a..c. % Use 1 Species 1968 1969 1968 -1969

Spine bursage 10B6 197 18 9 Abrosia tomentosa Large-spike spi kesedge 827 98 18 9 Eleocharis macrostachya Beakpod even1 ng pnmrose 84 8 40 T Oenthera canescens PraHie coneflower l 0 ~tibida columnaris Cl over T T Hedicago ~ Prostrate knotweed T Pol ego nom av i cul a re Plarns knotweed T Po le~onom bi corne Koch 1 a 105 355 39 Kochia scoparia J'OliiiSOn g r as s T ~ halepense rateuphorb1a T T Eupho rb i a s e rpe ns Snow - on- the-mountain 4 Eu~horbi a margi nata Sl a 4 T Si da Leprosa lliYWeed dogweed T T 01ssodi a papposa fiimleaf goosefoot 224 65 ~enopodium leptophyllum Total all species 2121 883 Based on differences in weights between grazed and ungrazed sample plots; -Indicates frequency on occurrence too limited for ~termination of use. Floristic composition of the immediately adjacent slope was striki ngly different from that in the bottom. The vegetation in ~e bottom is representative of most playa lake veg etation on the south plains, especially from big playas that are not under water except for s hort periods of time during the summer rainy period (Dr. Chester Rowel 1, 1968, un publis hed data). The s lope vegetation is more typical of t he s urrounding short- 9rass plains. Blue grama and buffalograss are the dominant species {tab le 2). This two species produced 96% of the vegetation on the slopes immediately adjacent to the playa lake bottom in both 1968 and 1969. A fluctuating water line due to periodic flooding of the bottom causes fluctuations in composition and production of the plants on this site.

69 Table 2. Production and utilization of the species on the Big Playa Lake slopes on the Texas Tech Research Center, 1968 and 1969.

lb./ac % Use 1 Species l 96g---rg69 1968 ~69

Blue grama 1345 1297 30 38 Bouteloua gracilis Buffalograss 546 338 T Buchloe dactlloides Pra1r1e sunf ower 60 T 85 Helianthus petiolaris Woolly plainta1n T T Plantago purshii Kochia T 3 Kochia scoparia "S'Tlriileaf goosefoot T 3 Chenopodium leptophyllum Mat euphorbia T Eu~horbia ser~ens Ye lowspine t istle 18 Circium ochrocentrum Little barley 3 7 Horde um pusi 11 um Snow-on-the- mountain T Euphorbia marginata Six-weeks fe scue T Festuca octaflora Veiny pepperweed T Lepidium oblongum Sand dropseed 41 Sporobulus cryptandrus Tumblegrass 5 Schennodadus paniculatus Total all species 1972 1694 Based on differences in weights inside and outside wire cages; -Indicates samples too sma ll for determination of utilization Tindicates amounts less than one lb. per acre. Although the cattle have access to the 472 acre pa sture, most of their grazing was confined to the playa bottom and immediately adjacent slopes. Utilization averaged 1 7% for the bottom and 25% for the slope vegetation in 1968 . In 1969, it averaged 34% f or the bottom and 24% for the slopes . Large-spike spikesedge and spine bursage furnished most of the grazing in t he bottom in 1968 while blue grama furnished the most on the slopes. Kochia and sliml eaf goosefoot were the most abundant and furnished most of the grazing in the lake bottom in 1969. Summary Spine bursage and large-spike spikesedge were the two most abundant and productive species in the playa lake bottom in 1968 while slimleaf goosefoot and kochia were in 1969. They also furnished most of the forage for grazing livestock. Blue grama was the dominant species on the adjacent s l opes. Hereford cattle utilized the playa lake bottom almost exclusively for the grazing period, although surroun ding blue grama range was available.

70 Additional ~bservations on the Contro l of Mites Attacking Grain Sorghum Charles R. Ward, Ellis W. Huddleston, John c. Owens and Donald Ashdown Introduction

Grain sorghum producers on the High Plains of Texas have become concerned about the Banks grass mite, Oligonychus pratensis (Banks), that first caused extensive damage to sorghum around Hereford, Deaf Smith County, Tex., at least as early as 1965. It has been found to attac k a wide range of hosts including grain and forage sorghums, corn, wheat, timothy, other gr asses, and dates. In 1953 damage to grain sorghum by t hi s ~t e was reported from the lower Rio Grande Valley of Texas (Griffith and Wene, 1953). Daniels et al. (1956) reported the mite to be a non-economica l pest of wheat; hOwever, widespread reports of mite damage and unus ual population increases on sorghum caused concern that the aites might spread to the large acreage of fall-planted wheat in the area and result in damage to this crop also. However, Hudd l eston et~ (1968) did not find this to be the case . Huddleston et. al . (1968) found mite damage to grain sorghum to be expressedas dTscoloration, drying and/or premature death of the leaves. The death and subsequent lodging of some mite infested plants was also observed. They described the symptomato- logy of the mite infestations in detail and stated that the mites developed in high numbers along the midrib on the underside of ~e lower leaves and progressed to the upper leaves and the heads.

Griffith and Wene ( 1953) found sulfur dust to provide excep- Uonal control of mites on sorghum. Demeton (Systox) and para- ~ion were reported to give the most consistent control on wheat (Harvey, 1954). Bacon et al. (1962) recommended ethion for mite control on corn in CalitornTa. Huddleston et al. (1968) tested ten acaracides and found Supracide (GS-l3005T, carbophenotliion (Tr ithion) , dis ulfoton (Di-Systox), Azordin, diazinon and demeton ~give effective mite control. These latter workers also found that 2 applications of any of the compounds tested would give significant reductions of mite populations.

Additional observations were made on the control of the Banks grass mite in the Hereford Area in 1968 after finding high infest- ition levels developing in some fields in August. Experimental ~ots for the 1969 studies were located near Pecos, Reeve~ County, Tex., where difficulty has been reported in mite control. Since simi l ar acaracide resistance patterns may be developing in the Rereford area these data are important to growers in this area 11 so .

1 Acarina:Tetranychida *A ssi stant Professor, Associate Professor, Graduate Research Assistant (Now at Iowa State University, Am es) , and Professor, Re s pectively, Entomology Section, Texas Te ch University, 2Lub bock. Personal Communication with Mr. Charles Neeb, Texas Agricul tural Extension Service, Fort Stockton, Texas.

71 1968.--An irrigated field of DeKalb F-64 variety of grain sorghum in the soft dough to early hard dough stage was selected for treatment. In the 1st test, 9 acaracide treatments were evaluated in a randomized complete block design with 4 replica tions. The plots were 60 ft. lon~ and four rows (40 in.) wide. The emulsifiable concentrated (EC) in the 1st test were applied to the center 2 rows on Sept. 6, with a nitrogen-pressured, hand carried sprayer equipped with 5 nozzles spaced 20 in. apart on the boom and calibrated to deliver 5 gal. of spray/acre. Candidate acaracides in the 1st test were: disulfoton, Supracide, carbophenothion, diazinon, parathion, Galacron, and Velsicol VCS-506. Oisulfoton EC was applied at 2 rates, 0.5 and 0.38 lb. AI/acre. A single application of 10% disulfoton granules (G) was made at a rate of 0.5 lb . AI/acre with an Ortho Whirly-Bird hand-operated applicator. All other materials were applied at the rate of 0. 5 lb. AI/acre . Post-treatment counts were made 6 days after acaracide applications by visual selection of 10 of the most heavily infested leaves from each plot. A single microscopic field of about 0.6 inch in diameter was selected in the most densely infested area on the leaf. All life stages (eggs , larvae, early and late instar nymphs, and adults) of mites in each microscopic field were recorded to aid in control evalu ation. Pre-treatment counts indicated an infestation gradient, so blocks were established across this gradient. Yield data were taken by hand harvesting what appeared to be the best 13 . l row ft. of sorghum in each plot . The sorghum heads were then threshed with a powered, small-plot thresher, weighed and yields co nverted to pounds per acre. A 2nd test consisted of aerial ULV applications of Supracide and diazinon at the rate of 0.5 lb. AI/acre. Although these formulations contain different amounts of AI/gal, each was applied at the rate of 1 qt./acre. The desired application rate of AI was achieved by dilution of the ULV formulations with the proper amount of xylene. Mite population and yield data were taken as in previous tests. 1969.--The studies were conducted in a heavily infested field of grain sorghum located west of Pecos, Tex. The sorghum was in the late bloom to soft dough stage at the time of acaracide application on Sept. 6. The test was divided into 3 phases to maximize data accumulation should adverse weather conditions pre vent the application of all of the 22 chosen test chemicals. The 1st phase, designed to evaluate those chemicals which had been tested for mite control in 1967 and 1968 in the Hereford area, consisted of 10 treatments replicated 4 times and arranged in a randomized complete block design. Materials included were : Supracide, Acarol, disulfoton, parathion, carbophenothion, chlorobenzilate, Acaralate and diazinon. All were applied at the rate of 0.5 lb AI/acre; disulfoton was applied both as a spray and as a granular formulation. The EC formulations were applied at a rate of 5 gal total mix/acre with the equipment described above; the granular disulfoton was applied with the hand applicator. The 2nd set of plots, using the same design, was treated with the following materials : BAY 93820, oxydemetonmethyl (Guthion), Monitor, Galecron, GS 27296, sulfur (dust), demeton, Velsicol VCS-506, and Dyfonate. The EC formulations were applied as described above at the rate of 0.5 lb AI/acre; the sulfur dust was applied with a hand-operated dust applicator at a rate of 20.0 lb AI/acre.

72 The 3rd phase included three compounds applied in a completely random design. The compounds included and the rates of applica tion in lb Al/acre were: wettable sulfur 20.0, carbaryl (Seven) 2.0, and malathion 0.5. The wettable sulfur and carbaryl treat me nts were applied with the same equipment as above; however, larger nozzles were used to allow application at a rate of 15 gal. total mix/acre. The malathion was applied at 5 gal. total 1ix/acre. Yield data were taken as in earlier tests except that 26.2 row ft. of sorghum were harvested in each plot. Observations were made on plant l odging in the plots to obtain an estimate of the effect of mite reduction on the incidence of charcoal rot as expressed by this indicator. Lodged plants i n 26.2 row ft. of sorghum were counted to give lo~ging estimates which were then converted to the number of lodged plants per acre. Discussion and Results 1968. --Analysis of the data from the 1st test indicated that al l materials except parathion, Galecron and Velsicol VCS-506 re sulted in significant population reductions over the check; ~wever, all of the compounds were apparently less effective than in t he previous year (table 1). Since pre-treatment counts were lower than in 1967, higher initial populations co uld not have ~en a factor. Again, disulfoton, Supracide and carbophenothion ure among the more effective insecticides tested. The 10% disulfoton G formulation applied topically to the plants was as effective as an EC formulation of the same material applied at the same rate. Data on numbers of mite larvae showed the two furmulations of disulfoton, Supracide , carbophenothion and diazinon applied at 0 .5 lb. Al/acre · to have a somewhat longer rffective residual action than the other materials tested. ~servations also were made on possible beneficial insects, but low numbers prevented any detailed evaluations . In the 2nd test (ULV applications of Supracide and diazinon) 1n anal.v~is of the six day post-treatment counts showed a significant reduction in mite numbers in the Supracide plots rompared to those in the check plots (table 1). A comparison between population levels in these plots and in an adjacent 1rea treated aerially with parathion indicated that both Supra cid e and diazinon were somewhat more effective than parathion in mite control. As in the previous tests, y ield data were not related to mite "pulation densities. The significantly lower yields of the ULV Supracide plots were probably due to severe phytotoxicity. The ~ rn encountered was apparently associated with the use of xylene to dilute the ULV formulation, as the s ame application rate of llie EC formulation failed to cause burn when applied under similar co nditions i n the 1st test. Burn was not observed in the Redla nd nriety used in 1967. 1969. --The lst phase of the Pecos tests included those themicals which had given s uperior mite control in the Hereford area. Al though results of control efforts in the Pecos area with some of these compounds were reported to be unsatisfactory 2, they ~re applied at 0.5 lb. Al/acre to allow comparison with the irevious year's data. As shown in table 2, the Supracide-treated ~ots were the only ones to have mite numb ers s ignificantly l ower llian the untreated check on the seventh day following treatment. Ill other plots had mite numbers about equal to or double those of seven days earlier. Although somewhat less effective than in llie Hereford area, Supracide gave the best level of control, and

73 an analysis of the yield data showed these plots to have a sig nificantly higher yield than any of the other plots . Extreme variation in the number of lodged or fallen plants was found, and lodged plants as well as many of the standing plants were heavily infected with charcoal rot, which probably was the major cause of the lodging . The 2nd phase showed some significant differences among treatment means (table 2), but none of the other test chemicals were as effecti ve as Su pracide, as indicated by the mite count and yield data. However, some of the less effective compounds included in e i ther tes t might give economical control at higher rates. The last test with three additional materials was applied to an adjacent area in the same field. None of the treatments in cluded gave effective control of the mites .

The difficulty in controlling the mites on ~orghum in the Pecos area had been attributed to 0-P resistance . The results of our tests show that the mites in the Pecos area were more difficult to control with the 0-P compounds than the mites in the Hereford area. Laboratory tests are planned to determine the LCso values for various compounds on mites from each locality. This comparative data should indicate resistance levels more accurately, and serve as a screening technique for compounds to be included in future field tests. Summary

A large population of Banks grass mites, Oli~onychus ~ tensis (Banks), was reported attacking grain sorg um ln th~re ~Deaf Smith County, Texas, area in 1967. A two year study in the Hereford area s howed that Supracide, disulfoton (both as granular and emulsifiable concentrate formulations) and carbo phenothion applied at 0.5 lb. AI/acre were the most effective treatments . Azodrin, diazinon and ULV Supracide offered some control capabilities at the same application rate . In both years, applications were made on fairly mature sorghum, and yields apparently were not significantly increased by reductions of the mite populations. Observations on parathion treated fields indi cated increased yields when mites were controlled on younger sorghum. Higher incidence of sorghum plant lodging was indicated in heavily infested fields. Further studies in 1969 near Pecos, Reeves County, Te xas, involving 20 acaracides, showed Supr.aci de was significantly more effective in control on the apparently more acaracide tolerant mites found in t hat area.

74 Table 1. Effect of selected acarac ides applied to grain sorghum at various rates for mite control. Hereford, Tex., Sept., 1968. Avg no. mites/microscopic field Acaracides and 6 dals after a~~licationa Test rates applied All Avg yielda no. in 1 b. AI/acre Larvae stages in lb/acre 1. Dis ul foton G ( 0. 5) 6.5 a 9.2 a 6,215 a Supracide ( . 5) 4.4 a 9.7 a 7, 344 a Disul foton EC (. 5) 4.5 a 9.8 a 6,027 a Carbophenothion ( . 5) 8.0 ab 1 5. 9 ab 6,512 a Diazinon (. 5) 10.1 abc 16. 5 ab 6,492 a Disulfoton EC (. 38) 12. 7 be 17. 4 ab 6,273 a Parathion (. 5) 13.0 be 22. 1 abc 6,805 a Galacron (. 5) 15. 2 cd 27.3 be 6. 141 a Velsicol VC S-506 (. 5) 14. 7 cd 34.8 c 6,273 a Check 19.6 d 37.2 c 6,750 a 11. Supracide ULV ( . 5) 2.7 a 5,528 a Diazinon ULV ( . 5) 9. 3 b 6. 7 27 b Check 15.1 b 7. 184 b Parathionb (. 5) 14. 7 7,629 aFigures followed by the same letter are not significantly different at the 95% probability level (Duncan's new multiple range test) . bNot included in the analysis as only a single replicate wa s sam pled . hble 2. Results of three tests involving 22 acaracide treatments to sorghum for mite control. Pecos, Tex., Sept., 1969. Avg no. mites/ Avg no. Acaracides and microscopic field lodged Test rates applied l b AI/ 7 days after plants/acre Yield in no. in lb AI/acre acre applicationa at harvesta lb/acrea 1. Supracide o.5 91. 3 a 500 a 3,770 a Acarol . 5 381. 9 b 1 • 125 a 2,935 be Dis ul foton (G) . 5 455.8 be 8, 500 a 3 ,457 bed Parathion . 5 508.8 be 6, 250 a 2,300 d Carbophen othi on . 5 550.0 be 4 ,250 a 2,442 bed Disulfoton (EC) . 5 569 . 1 be 4,750 a 2. 3 33 cd Acaralate . 5 622.4 be 3,500 a 2,389 cd Choloroben- zilate . 5 660.9 be 6,000 a 2,272 d Diazinon . 5 726.9 c 6.500 a 2,202 d Check 504.7 be 875 a 2,991 b 11. BAY 93820 • 5 152. O a 2,753 be Oxydemeton- methyl . 5 161. 4 a 2,428 bcde Monitor . 5 218.8 ab 2,572 bed Azinpho s - methyl . 5 263.5 ab c 2,332 def Galecron . 5 263.7 abc 2 '911 b Sulfur dust 20.0 269.0 abc 3,507 a GS 27926 . 5 307.0 be 2. 199 def Demeton . 5 353.7 c 1 • 971 ef Velsicol VCS- 506 . 5 364.7 c 2,143 def Dyfo nate . 5 497. 9 d l ,838 f Check 37 5. l c 2,457 be def - continued -

75 Table 2. - continued - 111 Wettable Sulfur 20.0 302 . 3 2. 198 Carbaryl 2.0 309.6 1 • 980 Malathion . 5 450.9 1 • 789 Sulfur dust 40.0 2,299 aFigures followed by the same letter are not significantly different at the 95% probability level (Duncan's new multiple range test). Literature Cited Bacon, 0. G., T. Lyons, and R. S. Baskett. 1962. Effects of spider mite infestations in dent corn in California. J, Econ . Entomol. 55 (6) :823-835. Daniels, N. E., H. L. Chada, D. Ashdown, and E. A. Cleveland. 1956, Greenbugs and some other pests of small grains. Texas Agric. Exp. Sta. Bull. 845. 14 pp. Griffith, R. D., and G. P. We ne . 1953. Mite injury to sorghum in the Lower Rio Grande Val ley of Texas. J . Econ. Entomol. 46 (6):1112-1113. Harvey, T. L. 1954. Chemical Control of a spider mite on wheat in eastern New Mexico. J. Econ. Entomol. 47 (4) : 593-597. Huddleston, E. W., C. R. Ward, T. M. Hills, and J. C. Owens. 1968. Evaluation of se lected insecticides f or control of mites on grain sorghum in West Texas. Texas Technological College Research Farm Reports. !CASALS Special Report 4.

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