A24-Lancaster Farming, Saturday, June 11, 1988 Cut Hay-Making Ri BY DAVE DOWLER Mercer Co. Extension MERCER Far too many far mers and scientists see nothing but uncertainties when it comes to for age harvest When should I cut? If I cut now, what will be the weather during drying? If I wait, will qual ity be higher than if the hay is rained on now? Would it be belter to store as low moisture silage, or bale? When should I bale? Those are some of the tradition al questions. More recently some have been added to them. Should I use a drying agent, a preservative, or both? Which one should I use and how much? We have devised a seven-step plan in Wisconsin that can turn these and other uncertainties into risks that can be ensured against and be managed. Generally, mak ing low-moisture silage is the best way to manage these risks, espe cially with the first cutting, or cut ting made in the fall. With this hay making plan you may not always be able to make hay in a day, but you will better know what you are doing when you follow it. And, you should be able to harvest a high-energy and high-protein crop for feed and for sale. Right day to cut? The greatest uncertainty asso ciated with hay and low-moisture silage production is the weather. The crop is ready for harvest of high-quality forage now. How much quality do I lose for each day I delay culling? Is it better to cut a little early or a little late to avoid wet weather? Will the rain hold off until the crop is dry enough to bale or ensile? It takes about 30 sunshine hours to field-cure non-condilioncd hay in the Midwest. In spring this is about 4 days. It increases to about 3 days in the summer. Check your weather records to determine the uncertainty (chances) of receiving 3 or 4 days without rain. In Wis consin this is about a 25% chance pretty low betting odds. Effective mechanical condiuon ing may remove up to 2 days from this drying time. Dry matter losses m the field range from 16 to 50 percent, depending on when and how much rain occurs, the moisture content, and the type of bale. Quality losses may be even gre ater. Wisconsin studies show that 1 inch of rain in the first 24 hours after cutting reduced carbohy drates (TNC) 20%, increased neut ral detergent fiber (NDF) 20%, and dropped relative feed value (RFV) on early cut alfalfa 14%. The same amount of ram on nearly dry hay reduced TNC 56%, increased NDF 45%, and lowered RFV of the same alfalfa by 30%. Energy was leached out, leaving a higher concentration of fiber which resulted in lower digestibili ty and intake. These losses occur in the form of leaf loss, respiration, and leaching of nutrients from the plant. Your conditions may not be the same as they are in Wisconsin. Your weather may be more pre dictable; or perhaps less predict able. You may be less likely to have grass or weeds mixed with your legumes. Even so, much of this plan will still be valuable to you. The plan The plan involves seven steps that integrate known technology into a system that elminiates as many days of field drying as possi ble. If we can eliminate 3 days of drying, the remaining dav becomes only a “risk” which can be managed for. Here is the plan: 1. Cut early Forages must be cut early (bud stage for alfalfa, as heads emerge from the boot for grass, etc.) to obtain optimum feed value, animal performance, and/or price. There is no substituc for this first step. As the accompanying table shows, digestibility dropped about 0.4% per day and intake per per cent body weight dropped about 0.04% per day, resulting in a loss of 1 lb. of milk per day, when alfal fa was left growing after the bud stage of maturity. In this study, bud-stage alfalfa was worth $156, $lB6, $207, and $331 per ton when fed to cows producing 80 to 100 lbs. of milk per day on 80:20, 63:37, 46:54 and 29:71 forage; grain rations, respectively, and where mid-bloom alfalfa was given a zero value. Farmers often delay cutting after the crop is at the proper stage hoping for “better weather.” How ever, a study in New York showed it was more advantageous to cut early and take a chance on the weather than to wait until the crop matured and lose most of the qual ity produced. Cows fed early cut, weathered hay produced 4 more pounds of milk per day than those fed late-cut, non-weathered hay. Using newer technological advances in a hay making system can help farmers capture the higher feeding value available in early cut forage without experiencing the field and weathering losses from ram. Hay auction prices range from $l6 per ion for manturc hay (low in quality according to Wisconsin Quality Tests) up to SIBS per ton for high-quality hay. So whether you feed the hay or sell it, you arc far belter off to cut it as early as you can. 2. Condition the crop Leaves dry rapidly; intact stems do not. Unless you do something to crack those stems open so the moisture inside can get out, you will have many of the leaves on the ground before the stems are dry •# enough to bale or ensile. The result will be a forage made up mainly of stems. However, crushed slcms even large oncs-will dry almost as rapidly as small leaves. Even if leaves remain on the stems, their quality will be higher if they dry quickly. At 80% mois ture when cut, respiration will cause a 2% loss of feed value per hour. However, at 30% moisture this loss is zero. Conversely, mechanical loss of leaves and fine stems range from 0.5% of the dry matter per treat ment or operation at 80% mois ture, and will increase to 2.5% of the dry matter per treatment at 20% moisture. Thus, the farmer needs to have the forage dry rapidly with little mechanical movement. As well as cutting the crop early in its growth cycle, cut it early in the day and crimp it so it will have ideal conditions in which to dry. A crop that is cut in lale afternoon or evening will do little or no drying through the night, but lots of respiring. Your losses can be high. The conditioner works best when the roll speed is 2 to 3 times faster than the ground speed. Set the tension so that the stems are being cracked. Meshing or fluted rolls should not touch. See the operator’s manual for proper adjustment of your machine. Have you' checked your conditioner lately? 3. Use a drying agent, too Using a dessicant, or drying sks With This Seven- agent, as it is sometimes called, along with mechanical condition ing can reduce the moisture con tent an additional 2 or 3 percentage points to as much as 10 percentage points during a 24-hour drying per iod. This dessicant or chemical conditioner is applied to the entire stem and leaves as the crop is being mowed. Several chemicals can be used for chemical conditioning. These include potassium and sodium car bonate (both alkaline salts) and sodium silicate. These are all naturally occurring salts. Some other products containing methyl esters of fats, vegetable oils, and animal fats to enhance the rate of drying are under study for possible use as dessicants. Recent research in Michigan has shown that these products work no better than potassium or sodium carbo nate alone. Since the crop is standing when dessicants are applied and won’t be cut until a few milli-seconds later, some dessicant materials may be labeled by the EPA as pes ticides because of claims made by the companies. Check with your state regulatory authority for their interpretation of this point. Dessicants are most effective when applied as a spray at the mower-conditioner. Some researchers have suggested plac ing the spray nozzles behind the reel and ahead of the conditioning rollers. It is difficult for the opera tor to monitor the nozzles when they are there, so application may not be as uniform. A roller conditioner works bet ter than a flail-type conditioner for this purpose. The rollers seem to help spread the materials evenly across the surface of the cut material. The application rate should be at least 30 gallons per acre for good coverage, which means you need to haul a lot of water to the mower and through the field. Recommended amounts of chemical include 5 lbs. of potas sium carbonate m 30 gallons of water to 7 lbs. of either potassium carbonate or sodium carbonate per acre in 30 gallons of water. We suggest 7 lbs. The cost of potas sium carbonate ranges from about 250 to 450 per lb. Thus, the recom mended application would cost between $2 and $4.50 per acre, which would work out to about $1 or $1.25 per ton of forage harvested. When relative humidity was 80%, we found no practice will speed the drying process. But when humidity was 20%, all treat ments were equal in enhancing the drying of the forage. They have been more effective in second and third cuttings than at the first. Chemical conditioners vary in performance mainly because of environmental conditions. Sun light, humidity, and wind are the keys. If laundry won’t dry on a clothesline on a particular day, hay will not dry in the field that day; it is as simple as that. Any cut hay will rewet to some extent from dew through the night. Studies have shown that crimped hay and chemically treated nay Alfalfa quality and relation to animal performance. Stagfr of Composition-% DDM DMI 4% FMC quality CP ADF NDF % %Bwa/lbs/dy.b Pre-bloom 21.1 30.2 40.5 62.7 2.08 87.1 First flower 18.9 33.0 42.0 61.6 1.97 77.2 Mid-bloom 14.7 38.0 52.5 54.8 1.48 66.2 a/with 20% Concentrate Kawas and Jorgensen b/wilh 54% Concentrate UW-Dairy Science seems to rewet faster during the night. It will dry out faster again the next morning after the sun comes up, however. 4, Windrow design Crimping and chemical dessic ants will permit water to leave plant stems rapidly. Heavy win drows, just like clothes piled in a basket, inhibit this moisture from dissipating into the air. In a Wis consin study, two windrows, one twice as wide and thick as the other, had moisture concentrations of 67% and 25% respectively, 7 hrs. after cutting. To continue the analogy of clothes drying for a moment; clothes will not dry when they are piled in the laundry basket; they need to be spread out on the line. In the same way, a narrow, thick win drow will not allow hay to dry nearly as rapidly as will a wide, thin one that exposes more of the forage to sunlight and drying winds. Make your windrow just as wide and thin as your baler or chopper can handle. To avoid leaf loss, do not turn or ted hay after the moisture percen tage falls below 40 to 50%. 5. Know the moisture Don’t guess the moisture per centage; measure it so that you can know for certain. Several electron ic devices are available, but we believe you can best use the oil bath method or a more desirable microwave oven method. Specif ics on these methods arc available from county extension offices or the ag bulletin office in Wisconsin and many other states. You won’t be able to apply the proper rates of preservatives & spoilage will occur if you don’t know the moisture percentage. Check several places in the win drow because dandelions and other weeds will cause a variation in moisture. 6. Bale at higher moisture Use of chemical preservatives such as propionic acid allow you to bale at higher moisture percen tages than you can without them. This, too, lets you get the hay out of the field more quickly. Research in Michigan, Minnesota, Pennsyl vania, and Wisconsin has come up with the following guidelines for preservative use: - High-moisture alfalfa hay(2s to 30% moisture) treated with an adequate amount of organic acid preservatives and baled properly, had quality comparable to that of heat-dried hay. - When preservatives were used, harvested ycilds averaged 140 to 300 more pounds per acre because the hay had experienced less field loss due to leaf shatter and reduced exposure to adverse weather. - Chemically treated hay had less temperature rise in storage than untreated hay baled at the same moisture. Thus, heat damage was reduced. When 25% moisture hay was stored without preserva tives there was usually mold growth. - Hay in small bales continues to dry in storage until it reaches an equilibrium moisture of about 11%. There is, of course, shrink age during this moisture loss, so it Step Plan is not recommended that you bale if the moisture is greater than 30%. - Treating and baling at 25 to 30% moisture allows the operator to start baling earlier in the morn ing and to continue later into the day. Baling with perservatives can begin 12 to 24 hours earlier than baling without preservatives. - Some growers consider big bale silage to be a short-term alter native if rain threatens. Large round bales can be baled at 40% moisture and either stacked and covered or stuffed into individual plastic bags. Although other arti cles published in this magazine have outlined advantages for this practice, there are also disadvan tages. For one, these bales tend to flatten out and fall apart. You need nearly twice as much twine to maintain a firm package. Silage bales also are difficult to move. Bag quality is a major drawback. Some have small holes even when new, and some will split at the seams or tear quite easily. Sunlight (ultraviolet radiation) can cause deterioration of some types of plastic. All of the above can lead to spoilage. Scientists in Kentucky have found that fermentation is poor. Thus, preservatives are prob ably needed. If rain is approaching, though, you could apply acid at the 2% rate (40 lbs. per ton) and store 40% moisture hay in large plastic bags if you are mindful of the above precautions. 7. Mow drying Some growers are including mow drying to help assure high quality hay. Adding mow or bam drying to the haying system- using unheated air - appears to be an important component for certain areas, such as northern U.S., where seasons are short, rain is frequent, and temperatures are relatively low. The addition of heal from a solar collector or other sources may further reduce drying lime. In some areas where it was pos sible to make only two hay cuttings per season, the operators are mak ing three cuts and storing as low moisture silage instead of hay. The same three cuts could be accom plished by baling at high moisture contents, using a preservative, and bam drying. Mow drying has a number of advantages: - Bale at 30 to 35% moisture to reduce leaf shatter. - Cut preservative rates in half if they are applied properly. - Permit proper curing of hay that varied in moisture when baled. - Solar drying can permit grea ter flexibility in the system. -Both large round and small square bales can be dried if the equipment is properly designed. If you go this round, don’t put more forage in your dryer than you can dry in 4 to 6 days. The costs of mow or bam dryers can vary. One Wisconsin farmer put a dryer in his mow for a total investment of $4,000. This aver aged out to $3.50 per ton of hay. Another spent $26,000 giving him a fixed cost of $l5 per ton. Design the dryer to deliver no less than 500 cubic feet of air per minute per ton of stored hay. The cost of electricity for the fan aver ages $3 to $3.50 per ton. Economics The costs and return from this system are outlined in an accom panying table. As you can see, using the cost assumptions that we did, the system will not pay itself when there is no rain and is barely economical when there is (Turn to Page A 25)