^lifornia- y fiftsftrve \ Division of Agricultural Sciences UNIVERSITY OF CALIFORNIA *.rtis > ICULTURB -?Y OCT 1 2 1969 OF CALIFORNIA K EUY HAY CUBE STORAGE AND FEEDING J. B. DOBIE R. G. CURLEY CALIFORNIA. AGRICULTURAL 'Experiment Station" Extension Service CIRCULAR 550 Hay cubes are dense, bite-sized morsels of hay which are field-produced by machines picking up hay from the windrow, or by stationary machines. Cubes have completely changed handling and feeding methods for alfalfa hay — nearly half a million tons of them are produced annually in California for cattle and sheep, and the figure is growing. This publication discusses the handling, storage, and feeding methods re- quired for cubes. Numerous illustrations depict the equipment and techniques involved. Design criteria for safe storage are also discussed. CONVEYORS DIES PRESS WHEEL CROSS AUGER BELT PICKUP HAY CHOPPER FEED ROLLS COLLECTING AUGER WINDROW Fig. 1. Principal parts and flow of hay through cuber. Hay is picked up from field, passes under feed rolls, through chopper, is carried by cross-auger to the compression unit, forced through dies by the press wheel, and cubes are then carried by conveyors to a trailer wagon. SEPTEMBER, 1969 THE AUTHORS: John B. Dobie is Agricultural Engineer in the Experiment Station, Davis; Robert G. Curley is Agricultural Engineer, Agricultural Extension Service, Davis. 2 HAY CUBE STORAGE AND FEEDING c ubed hay has been tested and accepted by livestock feeders in California because of its improved density, better flow and bulk-handling characteristics, reduced storage space, increased feed consumption by animals, and labor savings. Cube- making machines require well-cured hay, obtained from field curing only in arid irrigated regions such as the Central Valley of California; cubing with available ma- chines is mainly limited to alfalfa. The quality and density of cubes are reduced if more than 10 per cent of grass or other foreign material is present, or if the alfalfa is too mature. In 1969, the only cube-making machines available commercially are of the roller- die principle (fig. 1), which involves ex- truding forage through a circle of dies, using a roller for compressing the hay into cubes (the hay is chopped before it enters the compression chamber). Cube size and shape. Many sizes and shapes of cubes have been produced by various ex- perimental machines, but cubes now avail- able commercially are I14 inches square and vary from 1 to 4 inches in length. This size allows optimum feeding, has accept- able materials-handling characteristics, and can be produced at reasonable capac- ity with a farm-size power unit. Moisture content. Alfalfa hay should be cured to about 10 per cent moisture con- tent before cubing. Water is sprayed on the windrow of hay as it enters the cubing machine, resulting in warm cubes at 14 to 16 per cent moisture as they emerge from the machine. For safe storage, cubes should be cooled and dried by natural or forced aeration to 14 per cent or less moisture content. Excess moisture and heat in stored cubes causes mold growth, loss of quality and nutrients, and can result in loss of crop by fire. Density and volume. Density of cubed hay varies with moisture content, quality, and maturity of hay. Good quality cubes will be close to 30 pounds per cubic foot bulk density as they emerge from the machine. After cooling, natural drying, and han- dling, cubes will average about 25 pounds per cubic foot and require 80 cubic feet per ton for storage — this compares to about 10 pounds per cubic foot for baled hay when closely stacked, or 200 cubic feet per ton. Fines. Fines or trash (leaves, stems and chips of cubes) are not desirable in cubed hay, mainly because they adversely affect handling and storage, and can reduce feeding efficiency. A reasonable amount of fines (up to 10 per cent by weight) is usually acceptable (see discussion below). PRODUCTION, HANDLING, AND STORAGE Cubes are hot (120° to 140° F) as they emerge from the dies on the machine and are conveyed into a bin having a capacity of up to 4 tons. The filled bin is dumped into a transport truck of 6 to 25 tons capacity which, when fully loaded, is driven to the producer's storage. Elapsed time from forming the cubes to storage will average about 1 hour, during which time the average temperature of the load may drop about 20°F. If cubes are elevated directly into a storage building and piled up to 25 feet deep, a great deal of residual heat may be trapped in the pile. With normal conveying equipment (screw, belt, or chain), cubes will be dropped into a cone-like pile with the fines accumulated at the center. The fines impede natural air flow and make it difficult for residual heat to dissipate, so it is common practice to dump cubes on a concrete slab in shallow piles (fig. 2) and allow them to cool 12 to 24 hours before being deep- piled in storage. In desert areas where cover is not provided, cubes are sometimes stacked in deep piles directly from the cuber, and natural aeration is depended upon to remove residual heat from piles. Fig. 2. Cubes are clumped 3 to 4 feet deep on slab to permit cooling and hardening before being handled by conveyor or placing in deeper piles. Proper cooling of cubes is essential. Large storage structures are filled by various combinations of mechanical ele- vators and conveyors. Where space per- mits, a relatively inexpensive chain and flight conveyor elevating at about a 45 degree angle will do an excellent job of moving cubes to the maximum height; conveyor capacity should be about ]/ 2 ton per minute to minimize unloading time for the truck. If space is limited, a below- grade dump pit may be used, and a screw- fed bucket elevator used to raise cubes to the horizontal distribution conveyor. Such an arrangement may cost two to three times as much as the chain and flight elevator. A horizontal conveyor suspended under the peak of the roof distributes cubes the length of the storage structure. Screw, belt, cable and flight, or chain and flight con- veyors are all satisfactory provided con- veyor size and speed are adequate (table 1). Table 1 SPECIFICATIONS FOR CUBE CONVEYORS Type of conveyor Minimum width or diameter Recommended speed Capacity Method of removal Horsepower required for 200-foot conveyor inches tons per min. Screw 1(3 70 rpm 0.5 Drop-through 5.0 holes Troughed belt 16 300 fpm 0.5 Tripper 2.0 Flat belt 20 400 fpm 0.5 12.0 scraper Cable and flight. . 16 100 fpm 0.5 Drop-through holes 5.0 Chain and flight 16 100 fpm 0.5 Drop-through holes 5.0 Fig. 3. Cable and flight transport conveyor wtih belt cross-conveyor. The transport conveyor runs the length of the storage structure/ with drop-through holes every 8 to 10 feet in the upper conveyor. The cross-conveyor is carried on the frame of the return of the transport conveyor, and is swivelled to deliver in any direction. The cable is driven over auto wheel, as shown in figure 13. Flight or screw conveyors are com- monly used for distribution, partly because of the ease of unloading through openings in the floor of the conveyor. These square drop-through holes are the width of the conveyor floor and are spaced 8 to 10 feet apart. The conveyor deposits a ridge of cubes the length of the storage structure, with an angle of repose of about 45 degrees. A storage structure with cross- sectional dimensions proportioned as shown on page 6 provides maximum utilization of storage space without a cross-conveyor or spreader. Fines or trash in cubed hay tend to be concentrated directly under the delivery points of the conveyor system, since clean cubes tend to roll to the outside. A cross-conveyor (fig. 3) will carry cubes to a greater number of delivery points, thus spreading the total amount of fines over a greater area. While this is helpful if the conveyor is moved frequently, it still permits undesirable concentration of fines under each delivery point (fig. 4) thus providing suitable con- ditions for hot spots. A spinner-type spreader (fig. 5) will provide more uniform piling in storage but the fines are not thrown as far as the cubes, with the result that fines are spread over a space about 12 feet wide for the length of the storage area. The spinner can spread a thin layer of cubes over a large area so that they can cool before residual heat becomes trapped in the pile; the spinner also permits more efficient use of storage space in a flat-roofed building. A 4-foot diameter spinner operated at 125 rpm will throw li/ 4 inch cubes 15 to 18 feet horizontally (this is suitable, for example, for filling a 70-foot wide storage shed having a 4-in-12 roof slope). Driving vehicles on stored cubes will crush the cubes; this creates excessive fines and packs them, thus reducing normal air circulation. Cubes should never be me- chanically packed into deep storage. Storage structures for cubed hay should have smooth solid floors, rainproof roofs, and rain-tight sidewalls or sufficient roof overhang to prevent rain from blow- ing in. Smooth concrete floor is most satis- factory for easy removal of cubes by power scoop; for this type of handling, sidewalls should be reinforced concrete 4 to 6 feet up from the floor with metal or wood side- walls up to the maximum piling depth at the wall. Sidewalls should have ample strength to withstand the lateral pressure CONVEYOR SPINNER Fig. 4 (top). Pile of cubes re- sulting from cross-conveyor pil- ing, showing aeration duct (bot- tom) projecting from cubes. Fig. 5 (middle). Spinner-type cube spreader. Note approximate trajectory of fines and cubes. Fig. 6 (right). Cross-section of building providing maximum utilization of space for cube storage with single distribution conveyor. MAXIMUM PILING DEPTH ON WALL? H I pq « O H P h-3 H O a 03 03 03 03 o J3 JS ^03 03 (h 03 a O o 'o O o a a a a ffl 4j 03 3 03 Hi bC 03 bO 03 bO 03 I.S £ a . CO 00 CO ,-. CO 03 SI k ^ - ft a o 03 0> 03 ^ I - 1 f -1 3 O ° 73 J" g> a 03 73 «> M s o.9 S3 a !z; +3 o CO »* CO a ti *ao| ft * a „>> S 73 o CO CNJ CO CO 02 ^-4 00 •*< a 00 x '» k x -"2 ^ A 03 ^ X? CI .-C Ttl -H 00 ^H 03 m k - - ^ a o u <2 o .9 ■S»| +3 be ^ co -3 ft ■§ o 8 -^ bD ' oo t3 "ft •§ S 8 -^ bD > oo '-3 ^ S-73 ft -4— 03 > o a u 03 ^2 a pq co "? CO "* a o H m a >> ■§ S 8 00 rt^ 73- .'O a 9 -^ u 03 ^2 a +3 o pq CO ■<* »o •>* a a o (M co CO ^ *T3 ft CO 73 ft oo '43 ft oo '73 ft H CO X? N» *?* x ?k X?JR ^ CO «\ c,^: ■^t «\ © cc X X $ £ +3 ,4 bfl^ CO CO o CO CO o '3 -t- 3 J3 £ oo CNI 00 CO o o o o o O o o -^ 0) +s +J -^ +3 ■u ra w o 00 tNl co o oo CO CO c3 £ o S:"j mz ^p^-W^ iftSgadM^r ADJUSTABLE PANEL Fig. 1 1 (above). Alternate barn-floor design to eliminate handling cubes in lower part of storage. Note reduction in storage space. Fig. 12 (left). Recommended manger cross-section for a self-feeding cube barn. Sloping bottom re- duces buildup of fines in the manger. Adjustable panel may be lowered to stop or control flow of cubes and force animals to eat fines. 12 Fig. 13. Cable-cmd-flight cube feeder for livestock. Cubes are carried on lower run of con- veyor. Flights are shaped to push cubes to side. When manger is full, cubes carry along and fall into empty manger. The auto tire is partly inflated so that the cable runs in a groove. of cubes. Cubes can be stored in overhead bins from which the wagon can be loaded by gravity. A cross-conveyor on one end of the wagon distributes feed to the feed bunk as the wagon moves along. This equipment is often available on dairy farms, and can easily and relatively cheaply be adapted to cubed hay. It is the simplest and least expensive method of feeding cubes on a trial basis, particularly when equipment is already available. Labor costs are higher than for conveyor feeding, but when overhead and operating ex- penses for equipment are added the total cost is comparable to that of conveyor feeding. Wagon feeding is adaptable to large or widespread operations and to any terrain, and is increasing in popularity for large dairies. Dry stock can be fed separately with the same equipment in dairy opera- tions. The amount fed can be controlled to minimize waste and accumulation of fines. Wagon feeding is readily adaptable to cattle and sheep feeding. Portable self-feeders. Self-feeders capable of storing up to a week's supply of cubes merit serious consideration for some feeding operations. In the interest of over- all system economy, consumers might well consider subsidizing producers' storage in order to eliminate or reduce their own storage. Thus, where accessibility of supply permits, daily or weekly delivery of cubes from the hay producer directly to the con- sumer's self feeders may reduce over-all cost. Such a system shifts most of the cost of storage to the hay producer, or to some intermediate storage and delivery operation. Figure 15 shows a recommended design for a portable self-feeder. The capacity of this feeder in 8-foot lengths is about 2 tons. Allowing 1 foot of feeding space per cow, this would have ample capacity for 16 milking cows for 1 week. 13 Fig. 14 Feed truck unloading cubed hay into a feed bunk. U2 Ply Wood USE ALL EXTERIOR PLYWOOC Fig. 15. Portable self-feeder for cubed hay. An alternate design, Form 52-500, is available from the American Plywood Association, 1 1 19 A Street, Tacoma, Washington 98401. 14 Feeders should be located so they can be easily filled by highway transport from all-weather roads. Minimum drive width should be 15 feet, with no curbs on inside curves, and a minimum center line radius of 40 feet on curves. Self-feeders can, of course, be filled from the consumer's stor- age as well; this can be done by tractor scoop or by a truck-mounted conveyor. Self-feeder design modifications for smaller animals, such as sheep or calves, may be necessary to minimize waste. FEEDING CUBED HAY TO BEEF CATTLE Cubed hay may be fed in whole form to growing cattle, or may be fed crushed or ground as an ingredient in mixed rations for fattening. Various reports have shown increased gains where whole cubes have been fed, primarily due to increased feed consumption. Feeding methods for whole cubes are similar to those discussed for dairy cows. The wagon method of distribution is the most common, as most beef feeding lay- outs are too widespread for efficient use of mechanical conveyors. Self-feeding barns and small self-feeders can also be efficient methods for feeding whole cubes to growing cattle. Cattle require grain and concentrate as a major portion of their fattening ration. It is common practice to break up the cubes and mix them with grain to provide a single complete ration. Cubes will mix and feed reasonably well without break- ing, but most feeders feel that this permits selectivity by the individual animal, so that cows do not necessarily eat the balanced fattening ration. Cubed hay should not be ground too finely for cattle feeding. Some cattlemen use baled-hay hammermill equipment for grinding, but eliminate the bale-breaker and, usually, the grinder screen. Normally, all that is necessary is to retain cubes in the hammermill chamber long enough to assure that each cube will be struck and broken. Depending on the hammermill design, a coarse screen or breaker bar may be required. Some equipment manu- facturers are now making small simplified hammermills for cubes. Roller-type crushers have also been de- veloped for shredding or breaking cubes. This or the hammermill system works well, and each requires only a fraction of the power used for grinding baled hay. The increased capacity and reduced power for grinding, and the transport and labor saving in handling, are the principal ad- vantages of cubes over bales for fattening rations. Broken cubes can be introduced as the hay ingredient in any feed-mixing plant. Figures 16 and 17 show schemati- cally two simple mixing operations now in use. The method of feeding the fattening ration is not affected by replacing baled hay with cubes. Cube Crusher or Shredder Feed Mixer Fig. 16. Feed-mixing plant receiving daily delivery of cubes from supplier. Cubes are elevated into storage, conveyed to a crusher or shredder and then fall into mixer. Other feed ingredients are combined in the mixer and then conveyed to storage or directly to the feed wagon. 15 Whole Cubes Mixing type feed wagon with scales Cube Crusher Crushed Cubes for weighing.mixin^.and delivering the ration Fig. 17. Feedlot system, with large cube storage. Cubes are transferred to crusher by scoop, and a stockpile of crushed cubes is maintained. Same scoop is used to load mixing feed wagon. FEEDING CUBED HAY TO SHEEP Limited experience in feeding 1 14 -inch cubes indicates that ewes, bucks, and even weaned lambs can handle them satis- factorily after a 4- or 5-day training period. Ewes wintered on cubed hay are reported to come through the lambing period in excellent condition, and may even gain weight unless limited in hay intake. Some waste is experienced because sheep must break a 1 14 -inch cube in order to eat it. Methods for feeding cubes to sheep are not well established. Supplemental range feeding has been accomplished by drop- ping cubes on the ground from a wagon or truck, but this causes more waste than when fed in sheep-height feed bunks. The recommended method requires controlled filling of feed bunks from a side-delivery wagon, or use of small self-feeders of the type shown in figure 15. Sheepmen are cautioned to expect some waste of cubes due to dropping on the ground, particu- larly the first few days. After the training period, the waste is much less than there would be in using long hay. ACKNOWLEDGMENTS The authors acknowledge the assistance and cooperation of the following in developing and presenting this information: Magnar Ronning, Chairman of the Department of Animal Science, Davis, for material on dairy feeding; L. W. Neubauer, Department of Agricultural Engineering, Davis, and Win Engvall, Farm Advisor, Marin County, for material on storage and feeding structures; and Monte Bell, Farm Advisor, Glenn County, for material on sheep feeding. Drawings are by Pete Pankratz and J. L. Bumgarner, Senior Draftsmen, Davis. This publication was made possible through the cooperation of the California Agricultural Experiment Station and the California Committee on the Relation of Electricity to Agriculture. Co-operative Extension work in Agriculture and Home Economics. College of Agriculture, University of California, and United States Department of Agriculture co-operating. Distributed in furtherance of the Acts of Congress of May 8, and June 30, 1914. George B. Alcorn, Director, California Agricultural Extension Service. 15m-9,'69(J9585s)VL