UNIVERSITY OF CALIFORNIA COLLEGE OF AGRICULTURE AGRICULTURAL EXPERIMENT STATION BERKELEY, CALIFORNIA UTILIZATION OF SUGAR-BEET TOPS H. R. GUILBERT*, W. M. REGANt, and R. F. MILLERt Conservation and efficient utilization of sugar-beet tops offer great possibilities in California for increasing feed supply and meat production (fig. l) . Yield and Feeding Value The yield of moisture-free tops averages a lit- tle over 10 per cent of the beet tonnage. Based Fig. 1. --Success with beet-top silage in 1941 resulted in these stacks on Colorado ranches, in spite of increased labor shortage in 1942. (Courtesy of Through the Leaves , Great Western Sugar Company. Plans are under way to use topping machines and other mechanical harvesting devices during the coming season to facilitate economical har- vesting. Disposal of tops is one of the prob- lems in some of tb«se plans for using machinery. Mechanization is essential to economical har- vesting of tops, and top removal is necessary for the best use of the machines. In order to take advantage of opportunities to conserve and utilize this resource and to facili- tate mechanization, plans must be made in advance of harvesting through cooperative effort of the Agricultural Extension Service, sugar factories, beet growers, and livestock producers. To aid in this program, the following summary of infor- mation is presented. ^Associate Professor of Animal Husbandry and Associate Animal Husbandman in the Experiment Station. tprofessor of Animal Husbandry and Animal Husbandman in the Experiment Station. +Professor of Animal Husbandry and Animal Husbandman in the Experiment Station. upon last year's production of approximately 2,300,000 tons, the dry-matter yield of tops was about 230,000 tons. About 40 per cent of the dry matter of tops is in the crowns, and 60 per cent in the leaves. The average percentages of digestibility of tops found in trials with steers were: dry matter, 74; crude protein, 69; nitrogen-free extract, 82; ether extract, 39; and crude fiber, 75. The digestible nutrients in 100 pounds of beet tops compared on a dry-matter basis with alfalfa hay are as follows : Digestible Total crude digestible protein , nutrients , pounds pounds Beet tops used in diges- 13.5 63.9 Average of 6 California beet-top samples . . . 7.4 64.2 Average of 48 American and European beet-top 9.7 59.5 Alfalfa hay (dry basis). 11.7 55.6 [ 1 ] UN! VERSITY O F CALIFORNIA LIBRARY COLLEGE OF AGRICULTURE DAVIS The ash content of dirt-free tops is approxi- mately between 12 and 16 per cent of the dry mat- ter; the leaves, between 20 and 27 per cent; the crowns, between 4 and 7 per cent. The mineral content is greater than in most feeds and con- tributes to the laxative nature of the feed. Sometimes higher amounts of ash are caused by ad- hering dirt. Dirt not only lowers the value per pound by dilution but also adds to the laxative effect. The oxalic acid content of beet tops decreases in ensiling. Although positive calcium balances were obtained in steers fed on beet tops that contained considerable oxalic acid, it is recom- mended that 1/10 pound daily of calcium carbonate or ground oyster shell be fed to cattle receiving liberal quantities of tops in their ration, to counteract oxalic acid. The fermentation and spoilage loss in ensiling may be estimated at 15 per cent of the dry matter. The moisture content of silage averages about 70 per cent. A ton of beet-top silage has a feed-replace- ment value of about 450 pounds of barley or 700 pounds of alfalfa hay. Stated another way, the well-conserved tops from 1 ton of beets have the value of about 150 pounds of barley or 230 pounds of hay. These amounts, with a 15-ton beet yield, are equivalent to about 1 ton of barley or 1.5 tons of alfalfa hay per acre. Yield of silage varies with the beets but for the most part should be 3 to 5 tons per acre, with an average of about 4 tons (. fig- 2). Since Fig. 2. — A stack of beet-top silage, 14 x 32 feet, from 30 acres of beets. (Courtesy of Through the Leaves , Great Western Sugar Company.) complete recovery cannot be expected, 3 tons per acre may be used as a basis for estimating re- turns. With alfalfa hay at $20 per ton, beet- top silage has a replacement value of $7 per ton; or on a 3-ton yield, $21 per acre. Conservation It is estimated that less than 40 per cent of the 1942 acreage of beet tops was utilized for feed. Approximately 80 per cent of the acreage pastured was used by beef cattle. The estimated average yield of beef per acre was 60 pounds. The maximum utilization by pasturing may yield about 90 pounds of beef. If tops were harvested, made into silage or otherwise conserved and fed in mixed rations, the return per acre could be increased to between 150 and 250 pounds of live weight per acre. The estimated t'otal production of beef (live weight) from tops in 1942 was about 3 million pounds. This could be increased to 12 or 15 million pounds even with 50 per cent reduc- tion in acreage, if all tops were conserved. Under the best systems of field pasturing waste is great through trampling and shattering of leaves. In a test, steers ate approximately 60 percent crown and 40 per cent leaf when al- lowed free choice; whereas the percentage yield weight of crown was 40 per cent and leaf 60 per cent. This indicates to some degree rejection and waste of leaves in the field. Unfavorable weather often interferes with field pasturing, and pasturing may also interfere with preparation of land for other crops. Tops alone are not uti- lized by animals as well as when fed in mixed ra- tions. Many records in other states have shown that the return from silage fed to steers and lambs in fattening rations was three to five times the usual price for the tops in the field. The best method of conserving developed to date is stack silage. The tops should be stacked green or only slightly wilted. If too much moisture is lost, the tops will mold and decompose. The sides should be brought up straight, and successive lay- ers added so that the settled stack is at least 7 feet high . It is extremely important to have suf- ficient height and weight of tops so that they pack tightly, exclude air, and insure good silage. A round top on the stack will prevent penetration of rain during the winter. Such a stack, in a trial in Monterey County, resulted in good silage when fed out nearly one year after stacking (fig. 3) . Loss in these stacks does not appear to be , -. -, v %/ * . ■ . - Fig. 3---A good beet-top silage stack in Monterey County, 1941. The total of digesti- ble nutrients in the tops is at least one and one half times that in the pulp from the same beets. (Courtesy of Reuben Albaugh. ] [2] higher than in a trench silo. The use of alter- nate layers of straw increases access of air, with spoilage, and is not recommended. Stacks may be placed in the feeding corral, surrounded by a manger-type fence and the silage fed off the stack (fig. 4). Another convenient method is to stack 2 to 3 feet away from the out- side fence of the feeding corral (fig. 5). The Fig. 4. --Beet-top silage and hay stacked in a feed lot inside a manger-type fence. The lot has been heavily bedded with straw to conserve manure. (Courtesy of Through the Leaves . Great Western Sugar Company.) MKWDMMV Fig. 5---Beet-top silage stacked 2 1/2 feet from the fence and fed off the entire top of the stack daily. Tnis solves an important labor problem in feeding. (Courtesy of Through the Leaves , Great Western Sugar Com- pany"!) silage may then be fed between the stack and a manger-type fence. These methods will save labor in feeding compared with using a trench silo or stacking elsewhere. One of the plans for harvesting this year in- volves mechanical topping of the beets, windrow- ing tops mth a side-delivery rake attached to the topper, and subsequent plowing and loading of the beets. This should make possible loading the tops either by hand or with a pick-up loader and keeping the tops reasonably free from dirt , which is very important. Other possibilities or modifications may be developed for harvesting, without such mechanical aid the average cost es- timated by 43 Colorado growers of ensiling beet tops varied from $1.75 to $8.00 per acre, and averaged $4.10 per acre in 1941. Utilization On tops alone pastured in the field, cattle may be expected to gain 1 to 1.5 pounds daily; lambs from 0.18 to 0.22 pound daily. Access to hay or dry stubble, or use of supplementary grain adds variety and increases gains. For best re- sults pasturing should follow harvesting by a week or 10 days, and the area limited by fencing so that it is cleaned up in 10 days to 2 weeks. Good utilization requires keen judgment; pastur- ing an area 1 day too long may cost many pounds of gain, and moving 1 day too soon may cost many feed days. Choking of both cattle and sheep is common in pasturing. Crowns remain soft in silage and this difficulty is obviated. Fattening rations, in which beet-top silage is used to replace about one half of the hay normally fed or one fourth of the dry feed equi- valent of the total ration, have produced gains and finish on cattle and sheep comparable to those of standard rations. The addition of 0.1 pound of calcium carbonate or ground oyster shell for cattle and 0.02 pound for sheep, costs little and may be beneficial. The usual daily allowance of beet-top silage is 20 to 30 pounds for cattle and 1.5 to 2 pounds for lambs. Beet -top silage and hay may be used as feed for breeding cows and ewes , for growing out young stock, and even for finishing mature steers. More gain may be expected than on good hay alone or on tops alone. Dairy cows may be fed 20 to 30 pounds of sil- age daily along with hay and grains. Beet tops contain betaine from -which methyl amines may be formed, and cause fishy flavor in the milk. If the tops are fed after milking and otherwise un- der ordinary conditions of feeding tops, the quality of the milk is not affected enough to merit rejection. Suggested Procedure Many beet growers are not livestock men and most livestock men are not beet growers. This is the greatest obstacle in securing any immediate widespread utilization of tops. Progress will depend upon the extent that these two groups can get together on terms of mutual benefit and for the purpose of aiding the war effort. At least one large-scale Colorado livestock feeder has in the past found it feasible to haul tops as far as 10 miles from the fields in which they were grown. Wet beet pulp is being hauled in California at least 15 miles from the factory. Wet pulp contains more water than beet tops. This gives some idea of the possibilities of concen- trating tops for feeding at some distance from the field; a fact that has also been demonstrated in Monterey County. It should be remembered, how- ever, that the shorter the haul the more economi- cal the feed. To give some working basis for contract rela- tionships that should be mutually advantageous to [3] growers and feeders, adjustment to the local value of alfalfa hay and to the pasture value of tops is suggested. For example, a price for tops of 50 cents per ton of harvested beets would yield the grower having a 15-ton beet yield, $7.50 per acre. This is 50 per cent more than the common price of 30 to 35 cents per ton of beets, or $5.00 per acre for field pasturing. Using 3 tons of recovered silage per acre as a base and adding $2.00 per ton for trucking and stacking give a net cost to the feeder of $4.50 per ton; this allows a margin, for his protec- tion, between cost and the $7.00 per ton feed- replacement value — if the farm price of alfalfa hay is $20 per ton. Adjustment in price may be made according to whether the tops are in wind- rows, piled at the end of fields, or delivered direct from topping machines to trucks. If recovery of tops from the field is not satisfactory or is variable, a price would have to be made per ton of green tops, bearing .in mind that fresh tops may carry 5 to 10 per cent more moisture than silage, may contain consid- erable dirt , and that the average ensiling loss is about 15 per cent. Another possibility would be for growers to contract to feed cattle or sheep furnished by livestock men for an agreed price per pound of gain. Some such an agreement would yield more to the grower than he could get in any other way ex- cept feeding the tops himself. In many cases there would be no market for pasturing because of lack of fencing, presence of adjacent crops, and other conditions. Removing of tops would facilitate mechanical harvesting, reduce cost, avoid trampling of ground, avoid delay in prep- aration of soil in the fall, and prevent spread- ing of plant disease and obnoxious weeds that may result from pasturing. Feeders would secure a good feed at favorable cost, compared with other feeds and the price of livestock. Since feeders assume numerous risks, and since for most of them beet tops would be a new feed, their margin of safety should be ample to make the enterprise attractive. Combined ef- forts of the two groups could add much to the badly needed meat supply. Several possible use set-ups are suggested: 1. Stacking for convenient feeding at exist- ing dairy, beef-cattle, or lamb-feeding plants in the vicinity (figs. 6, 7). 2. Arrangement for conservation of beet tops and utilization by large feeding plants. Fig. 6. --Beet-top silage cut with a hay knife and fed from the end of a stack. This will pre- vent spoilage when the amount fed daily is too little to take off a layer from the entire top of the stack. (Courtesy of Through the Leaves , Great Western Sugar Company.] Fig. 7. --In recent experiments conducted at the Belle Fourche Field Station, Newell, South Dakota, lambs returned $1.25 to #1.36 for the tops from a ton of beets on the basis of 1937- 1940 lamb and feed prices. (Courtesy of Through the Leaves , Great Western Sugar Com- pany.) 3. As an emergency measure, locating feeding grounds near centers of local beet production and bringing the livestock to the feed has great possibilities. If fairly well-drained ground can be found and most of the feeding done before the worst of the muddy season, satisfactory re- sults should be obtained. Cheap, temporary cor- rals could be built and hay and other feed brought to the feeding grounds. Such a plan for feeding lambs could readily be worked out with panels and portable feed troughs used in creep-feeding operations. The value of the manure from feeding opera- tions near the fields should not be overlooked. March, 1943 [4]