DECLARATION OF DR. DANIEL J. UNDERSANDER
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`I, Dr. Daniel J. Undersander, being of legal age do hereby declare that all
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`statements made herein of my own knowledge are true and that all statements
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`made on information and belief are believed to be true; and further that these
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`statements were made with the knowledge that willful false statements and the like
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`so made are punishable by fine or imprisonment, or both, under Section 1001 of
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`Title 18 of the United States Code.
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`Date: 04/13/2016
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`/Daniel J. Undersander/
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`Daniel J. Undersander
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`(electronically signed with permission)
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`TABLE OF CONTENTS
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`TABLE OF CONTENTS
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`Introduction ........................................................................................................ .. 1
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`Introduction .......................................................................................................... 1 
`I. 
`I.
`II.  Qualifications and Compensation .................................................................... 1 
`II.
`Qualifications and Compensation .................................................................. ..l
`III.  Forage ............................................................................................................... 2 
`III.
`Forage ............................................................................................................. ..2
`IV.  Forage Harvesting............................................................................................. 8 
`IV.
`Forage Harvesting ........................................................................................... ..8
`Mowing ............................................................................................................................. 8
`Mowing ........................................................................................................................... .. 8
`Drying ............................................................................................................................. 11
`Drying ........................................................................................................................... .. 11
`Harvesting ...................................................................................................................... 14
`Harvesting .................................................................................................................... .. 14
`Additional processes.................................................................................................... 17
`Additional processes .................................................................................................. .. 17
`Important Considerations During Forage Harvesting .................................... 21 
`Important Considerations During Forage Harvesting .................................. ..2l
`Reducing wheel traffic in the field. ......................................................................... 22
`Reducing wheel traffic in the field. ....................................................................... .. 22
`VI.  Changes in Forage Harvesting........................................................................ 25 
`VI. Changes in Forage Harvesting ...................................................................... ..25
`VII.  Summary of Market Forces ............................................................................ 29 
`VII. Summary of Market Forces .......................................................................... ..29
`VIII.  Terminology ................................................................................................ 31 
`VIII.
`Terminology .............................................................................................. ..3l
`IX.  Additional Resources ...................................................................................... 33 
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`V. 
`V.
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`IX. Additional Resources .................................................................................... ..33
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`I.
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`Introduction
`1.
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`I have been retained by H&S Manufacturing as an expert in
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`connection with petitions for Inter Partes Review of U.S. Patent Nos. 7,310,929,
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`8,166,739 and 8,863,488, as well as in connection the related federal district court
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`proceeding (Oxbo Int’l Corp. v. H&S Mfg. Co., No. 15-292-jdp (W.D. Wis. 2015.
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`This Declaration is my direct testimony in relation to forage, forage harvesting
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`practices, equipment for forage harvesting, and other matters I was asked to
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`address. In making this Declaration, I have reviewed the common specification of
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`the U.S. Patent Nos. 7,310,929, 8,166,739 and 8,863,488.
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`II. Qualifications and Compensation
`2.
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`I am a Professor of Agronomy at the University of Wisconsin-
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`Madison and have held that position since 1988. Also since 1988, I have been
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`actively involved with the University of Wisconsin Forage Research and
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`Extension. My responsibilities with the Extension service regularly require me to
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`be in the field working with and training farmers and industry groups in forage
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`management. Because I have spent my entire career in this field, I have great
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`familiarity with forage harvesting practices and the equipment used to accomplish
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`the harvest.
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`3.
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`I have more than 40 years experience with hay and haylage making.
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`Over this period, in addition to my hands-on field work, I have conducted research
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`activities, published articles, presented seminars, and trained forage industry
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`workers concerning forage harvesting practices and equipment. During my career,
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`I have written over 1300 publications related to forage production and harvesting
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`management. My qualifications are presented more fully in my curriculum vitae,
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`which is attached to this Declaration as Appendix A.
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`4.
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`5.
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`I do not have any previous experience in court proceedings.
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`I am being compensated for my time spent reviewing materials,
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`forming my opinions and in preparing this Declaration at the rate of $200 per hour.
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`My compensation is not contingent upon my testimony, the outcome of the
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`proceeding or any testimony that I may give.
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`III. Forage
`6.
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`Forage is the vegetative portion of plants (leaves and stems). Forage
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`includes plant species such as alfalfa, clovers, grasses, wheat, oats, barley,
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`sorghum, and sudangrass. Forage is grown for multiple purposes including
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`reducing soil erosion, increased carbon fixation and animal feed. Ruminant
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`animals such as cattle, sheep, bison and horses (technically a non-ruminant but
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`with enlarged cecum for forage digestion) have evolved using grasslands as a
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`primary source of food. These animals can digest the cellulose in forage, which
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`non-ruminants (including humans) cannot. Further, these animals require the fiber
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`from forage for good health. (Van Soest, 1982; National Research Council
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`(“NRC”), 2000; NRC, 2001)
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`7.
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`A primary consumer of harvested forage is dairy cattle, due to the
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`high energy and protein needs of milking cows. In the United States,
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`approximately 40% of harvested forage (60 to 70% of the alfalfa) is fed to dairy
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`cattle. The remaining 60% of harvested forage, including alfalfa and grass, is used
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`for beef cattle, horses, sheep and other livestock.
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`8.
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`Forage is generally harvested as either hay, or haylage. “Hay” is
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`forage which is harvested after drying down to a moisture content of 14% to 20%.
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`Hay is harvested into bales. Equipment for harvesting hay is known as a baler.
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`Bales of hay are usually round or square and may range in size from 50 lb to 1 ton.
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`Once baled, the hay must be stored in a dry place.
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`9.
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`Some advantages of hay include the simplicity of storage and feeding,
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`and less expensive equipment for harvesting. Some disadvantages of hay include
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`the amount of time required for forage to dry down to the necessary 15% or less
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`moisture content, which can be 3- to 6-days. This period of time can be difficult to
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`reliably achieve in some regions or climates, due to the prevalence of rainfall.
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`10.
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`“Haylage,” or “silage,” is forage which is harvested at a moisture
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`content of 50-65%. Equipment for harvesting haylage is known as a harvester or a
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`chopper. The harvested haylage is chopped and typically stored in a way to limit
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`oxygen exposure and allowed to ferment, producing primarily lactic and acetic
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`acid. Such oxygen-limiting storage may be silos, bunkers, or harvesting into bales
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`and wrapped in plastic (often referred to as “baleage”).
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`11. Because haylage is harvested at a higher moisture content and requires
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`less drying time than hay, some advantages of haylage include the ability to
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`produce higher quality forage when the potential for rain is high, and the ability to
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`get forage off the field faster to enhance the yield of the next cutting. Some
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`disadvantages of haylage include more expensive equipment for harvesting, and
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`the requirement of specialized storage structures/plastic wrapping. Haylage will
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`begin to mold and heat whenever exposed to air so it must be fed to animals
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`rapidly after being removed from an oxygen-limiting storage. In addition, the
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`higher water content of haylage makes transport for marketing/reselling difficult
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`and expensive.
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`12. The forage quality of hay and haylage are comparable. Either can be
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`better or worse than the other depending on the conditions during the harvesting
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`and storage process.
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`13. Forage is typically harvested numerous times throughout a growing
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`season. The number of harvests varies with the geographic location and climate.
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`Generally, the northern-most growing regions of the United States get 3 or 4
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`harvests per year. An area stretching from Southern Minnesota down into Iowa
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`often get 4 or 5 harvests per year. The number of annual harvests gradually
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`increases to 8 to 10 per year in southern California, Arizona, New Mexico and
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`Florida. In more arid climates, such as parts of the Western, Southwestern and
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`Southern United States, forage is typically harvested as hay (Barnes et al., 2007)
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`14.
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`In the Midwest and Northeast areas of the United States, forage is
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`harvested both as hay and as haylage over the duration of the year. For example,
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`the first harvest of the year may be done as haylage because of high rain potential
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`in the spring, decreasing the ability to reliably make hay. And also, on dairy farms,
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`the need to refill silage structures that have been depleted over winter. Subsequent
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`harvests may be done as hay because of better weather conditions for drying forage
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`and a desire to have an alternative forage with higher effective fiber for dairy cattle
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`and other growing animals. The final harvest of the year may again be haylage
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`because of the need to refill silage storage structures for winter.
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`15. High quality forage is important because it provides adequate
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`nutrients and energy for good growth or milk production. Increased animal size,
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`and increased milk production mean more profit for the farmer. The quality of
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`forage can be judged by a number of factors including crude protein content, fiber
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`(neutral detergent fiber, NDF) content and fiber digestibility. The user desires
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`forage with adequate protein for the animal being fed (10 to 16% depending on
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`animal), fiber above 1.2% body weight but low enough not to restrict feed intake,
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`and high fiber digestibility. The quality of forage is dependent upon plant species
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`and harvest date. Generally legumes, such as alfalfa or clover, are lower in fiber
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`and allow the animal to produce more milk or weight gain.
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`16. However, all forage are high quality when young and decline in
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`quality as the growth gets older. Generally the plant becomes more lignified and
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`stemmy with age. Stems have lower quality than leaves and lignification reduced
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`digestibility of the stems. Data from our studies (Buxton, 1996; Undersander,
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`2015) indicate the alfalfa increases 0.4 NDF per day and the digestibility of the
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`fiber declines 0.4 per day. Younger forage harvest results in stress on the harvested
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`plants and reduced yield, due to inability to completely recover from previous
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`harvest. So farmers must balance the quality in earlier harvested forage against the
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`advantage of higher yield from later harvested, more mature forage (Carter and
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`Sheaffer, 1982; Undersander, 2016).
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`17. The data in figure 1 below shows that advancing alfalfa maturity
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`resulted in reduced milk production (Kawas et al., 1989). The reduction could be
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`reduced but not completely offset by feeding more grain. Note also that the
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`increase in milk production from less-desired midbloom alfalfa to the more-desired
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`and higher quality prebloom alfalfa was about 20 lbs per day per cow. With milk at
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`$18/hundredweight, the increased production is worth $3.60 per cow per day.
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`18. Dry hay is often marketed based on Relative Feed Value (RFV). RFV
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`is an index of energy intake, the higher the RFV the greater the energy intake. An
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`RFV of 100 corresponds to full bloom alfalfa (nonlactating cow feed) and an RFV
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`of 150 is suitable for feeding to dairy cows. Figure 2 below shows that farmers
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`have paid a premium for high quality hay in tested hay Auctions across Minnesota
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`and Wisconsin (Undersander, 2004a). Actually hay is marketed nationally based
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`on RFV because of the general recognition of increased milk production from
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`higher quality hay.
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`IV. Forage Harvesting
`19. Forage harvesting processes vary by climate region, preference of the
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`grower, size of the field, and types of equipment available for sale in the area. But
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`generally, forage harvesting includes the following steps. First the crop is cut.
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`Second the crop is dried to the desired moisture content. Third the crop is
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`harvested and stored.
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`Mowing
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`20. Forage must first be cut off and laid out to dry before harvesting for
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`hay or haylage. The two major types of forage mowers are sickle bar mowers and
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`disc mowers. A third type of mower, flail mowers, are sometimes used for green
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`chop or bedding but seldom used for hay or haylage since the forage length is long
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`and variable and they tend to add more dirt to the forage. The older mowing
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`system (still in use) is to cut with a sickle mower. This mower has a series of
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`triangular-shaped blades that move back and forth horizontally across a stationery
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`edge. This mower was developed in the late 1800’s where the mower was pulled
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`by horses and the wheels of the mower provided the power for moving the blades
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`back and forth to mow the forage.
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`21. Some sickle bar mowers use a reel to fold the forage over the knife.
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`These mowers require about 50% less power per foot of cut length than disc
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`mowers. Open station tractors (those without cabs) can be used. Sickle bar mowers
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`typically cost about 10 to 20% less per foot of cutter bar. Sickle bar mowers tend to
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`have less mowing skips in light crops than disc mowers.
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`22. On the other hand, sickle bar mowers typically require more
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`maintenance since they have more moving parts (especially those with a reel) than
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`disc mowers. Also knives must be sharpened and broken blades replaced. The
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`increased labor and cost for maintenance of sickle mowers have caused many
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`farmers to move to disc mowers.
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`23.
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`In the 1970’s, disk cutterbar mowers were introduced to North
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`America. These machines had been used in Europe for grass for many years. The
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`early models had a single gear box for all discs so that if one blade hit something
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`and a gear tooth broke, the whole gearbox, and therefore the entire cutter bed,
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`would suffer an expensive failure. Modern disc mowers have separate hubs for
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`each disc across the cutting width, thus any damage is to just one disc and not the
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`entire cutting bed. Design improvements have also been made that allow quick
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`change of broken blades.
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`24. Disc mowers will cut better in lodged and tangled crops. They also cut
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`fine stem grasses, such as timothy, tall fescue, or bermudagrass, better. Modern
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`disc mowers will generally cut through gopher mounds and ant hills. It should be
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`noted that different blade types are available, including flat (for less dirt pickup but
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`also reduced forage pickup), angled at 8 to 14o (for better pickup of lodged forage
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`with increased dirt), stone knives and others.
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`25. Disc mowers do not need a reel, therefore these mowers have fewer
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`moving parts. However a tractor with cab is recommended since the rotating discs
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`can throw things forward and hurt the driver if there is no cab on the tractor to
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`protect the driver. Disc mowers require about 50% more horsepower per foot of
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`cutter bar.
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`26. Speed of cutting is limited by available power, field roughness and
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`other factors that determine the speed at which the cutting system can operate
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`without pushing the crop forward and leaving a ragged, uneven cut. This speed is
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`about 5 to 8 mph for sickle mowers and 12 to 14 mph for disk cutterbar mowers,
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`respectively, though systems are being tested which can harvest at twice the speed.
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`27. When making hay or haylage, leaves dry fast and stems slowly. In the
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`1960’s conditioners were introduced to increase the drying rate of stems. This tool
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`is located behind the mower cutter bar, and either scrapes or breaks the stem so
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`that it dries faster. Many farmers thought that with a conditioner they could
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`immediately place the hay into a windrow, covering 25 to 40% of the cut area,
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`rather than a wide swath as they had done before the adoption of conditioners. This
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`could reduce the need to rake hay from the swath into the windrow. However, this
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`theory did not take leaf drying into account. Research has shown that forage should
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`be conditioned for hay or haylage but placed into a wide swath to dry leaves rather
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`than immediately placed into a windrow.
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`Drying
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`28. For crops which are only harvested once per year, for example corn,
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`there is sufficient time to allow the corn to dry down to the appropriate moisture
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`level while standing in the field, before harvesting. However, as discussed above,
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`forage can be grown and harvested multiple times per year, and the need to harvest
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`high quality forage rather than letting it mature and dry, make it economically
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`unfeasible to wait for forage to dry to the desired moisture level standing in the
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`field.
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`29. Forages are approximately 72 to 80% moisture when cut. They must
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`be dried to approximately 60 to 65% moisture for haylage (silage) or to
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`approximately 15% or less moisture for hay. If haylage/silage is ensiled when
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`wetter than 65% moisture the fermentation may produce butyric acid which
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`reduces the palatability of the silage. Silage wetter than approximately 70%
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`moisture content may also have juices run out of the silage. This represents a loss
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`of sugar and starches (energy) and protein from the forage. This leachate is also
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`considered an environmental hazard (Graves, R.E. and Vanderstappen P.J. 1993;
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`Curell and Lee, 2011).
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`30. Hay baled at greater than approximately 15% moisture content will
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`heat which: (a) results in an energy loss; (b) may grow molds which consume
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`nutrients, sugars, and starch (further energy loss); (c) respire, which causes heating
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`and may result in hay fires, produce toxins detrimental to animal health and
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`decrease food intake; and (d) produce spores which, if inhaled cause lung disease
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`in both animals and humans.
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`31. The faster the forage dries the sooner it can be harvested, minimizing
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`the potential for rain damage and the sooner the next growing cycle of the forage
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`can begin. Faster initiation of regrowth results in higher yield for the season.
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`Therefore a number of processes and equipment may be used to speed up the
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`drying process.
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`32. The general pattern of drying forages is shown in the figure below.
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`(Digman et al., 2011). When forage is cut, it has 75 to 80 % moisture and must be
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`dried down to 60 to 65% moisture content for haylage and down to less than about
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`15 to 20% moisture content (depending on bale size) for hay (lower figures for
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`larger bales) (Digman et al., 2011).
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`Sequence of Drying Forages
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`Stomatal opening
`Phase I
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`Conditioning
`Phase II
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`Weather regulated
`Osmotic & Cell forces
`Phase III
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`Time
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`80%
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`70%
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`Moisture
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`20%
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`33. The first phase of drying is moisture loss from the leaves through the
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`stomates. Stomates are the openings in the leaf surface that allow moisture loss to
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`the air to cool the plant and carbon dioxide uptake from the air as the plant is
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`growing. Stomates open in daylight and close when in dark. Cut forage laid in a
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`wide swath maximizes the amount of forage exposed to sunlight, keeping the
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`stomates open and encouraging rapid drying which is crucial immediately after
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`cutting. Plant respiration continues after the plant is cut and gradually declines
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`until plant moisture content has fallen below 60%. Therefore rapid initial drying to
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`get forage moisture below 60% will reduce the loss of starches and sugars and
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`preserve more dry matter and total digestible nutrients in the harvested forage. This
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`initial moisture loss is not affected by conditioning.
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`34. The second phase of drying (II) is moisture loss from both the leaf
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`surface (stomates have closed) and from the stem. Conditioning can help increase
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`drying rate during the second phase. Conditioning to break the plant stems every
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`two inches allows more opportunities for water loss since little water loss will
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`occur through the waxy cuticle of the stem.
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`35. The third and final phase of drying (III) is the loss of more tightly
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`held water, particularly from the stems. Conditioning is critical to enhance drying
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`during this phase.
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`36. Thus the recommended management for harvesting forage is to mow
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`it, condition it and place it into a wide swath for rapid leaf drying (though some
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`farmers immediately place into windrow and suffer higher respiration losses of
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`sugar and starch). After about 24 hours laid in a wide swath, the forage should be
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`raked into a windrow for harvesting (for haylage) or for continued drying (for hay).
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`The windrows will continue the drying process, minimize leaf bleaching and leaf
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`loss. Many farmers merge multiple swaths into a single windrow so that the
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`harvester (either baler or chopper) operates more efficiently and makes fewer
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`wheel tracks on the field.
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`Harvesting
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`37. When forage has reached the appropriate moisture it can be harvested
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`for either hay or haylage.
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`38. Forage can be harvested for hay when the moisture content is
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`preferably about 15% or less. If hay has a higher moisture content it will heat and,
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`possibly, mold. Some farmers harvest forage at around 18 to 22% moisture, and
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`then add a hay preservative to retard heating and mold growth of the forage. The
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`preservative is generally a product containing propionic acid or acetic acid and is
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`sprayed on the hay as it goes into the baler (Undersander, 1999).
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`39. There are a variety of commonly-created bale sizes. Some balers
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`make large round bales, which are primarily for use where the hay is fed on the
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`farm where it is grown. Round bales can range in size from 4ft x 5ft to 5ft x 6ft
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`with a weight range of 500 to 1500 lb. Round bales can be left outside with less
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`weather damage but are more difficult to transport so not often re-sold or moved
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`any great distances.
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`40. Hay can also be baled into square bales. The older system is small
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`square bales (approximately 14 inches wide, 12 inches high and 3 feet long). These
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`bales weigh approximately 40 to 70 lbs. These type of bales are seldom used on
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`larger farms due to the higher amount of labor required for handling, but are
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`favored by horse owners where feeding is often done by hand. Newer square bales
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`make 3ft by 3ft by 6ft up to larger 4ft by 4ft by 6ft. These bales weigh 600 to 2,000
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`lbs. and are handled by machine, thus saving on labor. At the time of feeding, these
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`bales can be handled by a tractor or a skid steer loader.
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`41. Forage harvested for haylage/silage is chopped into 1 inch theoretical
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`lengths, blown into a wagon or truck, and hauled to where it will be stored.
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`Silage/haylage was historically stored in tower silos made of concrete or steel.
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`However, these are less used today as herd size has increased, due to slow
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`unloading rate and the longer time required to feed the animals. Most
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`haylage/silage is now put into ground-level storage, such as a bunker, pile or tube.
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`The storage must be filled quickly (within 2 days) to prevent heating and forage
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`quality loss. As herd size has increased, the volume of forage storage has
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`increased. The larger storage facilities require larger equipment to fill in a timely
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`manner.
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`42. Often, the forage harvesters are used for both alfalfa/grass and corn
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`silage (with different headers). Increased corn silage use for dairy cattle has caused
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`many farmers to buy larger choppers, and these larger choppers are then also used
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`on the alfalfa and grass.
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`43. Many smaller scale operations can only harvest 10 to 20 acres per
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`day, due to the size of equipment used and labor shortage and expense. Larger
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`equipment capable of harvesting more acreage is often too expensive for small
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`scale farming operations to justify owning. This means that forage harvesting may
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`extend up to 10 to 14 days when the small equipment is coupled with rain days
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`where harvesting is prevented. This lengthy period of time to harvest results in
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`gradual decline in forage quality from start to finish of the harvesting period, and
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`variable quality haylage in the being fed. The other consideration is that if a farmer
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`is harvesting forage himself for several days, he may not be paying sufficient
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`attention to the dairy herd. This can result in delayed breeding, unnoticed herd
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`health issues and failure to adequately balance the ration for high milk production.
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`44. Over the last 25 years, contract harvesting has become a big business
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`in the Midwest, responsible for harvesting an estimated 40% of forage. The
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`advantages of custom harvesting are that all forage is quickly harvested (often
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`within 1 to 2 days), the farmer avoids the need to buy machinery and to hire labor
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`for harvesting.
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`Additional processes
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`45.
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`In addition to the above steps, additional processes can optionally be
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`performed as part of harvesting forage.
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`46. One step is raking which is done to narrow the swath for the baler or
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`chopper, and also to move the wetter material at the bottom of the windrow to the
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`outside.
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`47. Every time hay is raked there is some leaf loss, since the hay is rolled
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`along the ground and shaken causing leaf drop. So one should rake strategically.
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`The drier hay is at raking, the greater the leaf loss. This is shown in the figure
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`below where forage raked below 40% moisture suffered over 7.5% dry matter
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`losses and greater forage quality loss since the dry matter loss is generally leaves
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`which are higher in forage quality than stems. If possible, raking alfalfa at moisture
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`contents between 30 - 40% as a good compromise between low leaf loss and good
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`drying. Leaf loss can be extremely high if raking at 20% moisture or less. Hay that
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`is almost dry is less likely to shatter if raked in the early morning when the dew is
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`still on.
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`48. Parallel-bar rakes were the dominant machines used to manipulate
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`forage crops in the Upper Midwest for many years, but sales of these machines are
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`declining annually. They are considered to be less aggressive (with reported leaf
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`losses of 2.1 to 3.5% at 40% moisture), though more expensive than wheel rakes
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`and are not available in wider widths. Parallel-bar rakes have a powertrain and
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`more moving parts to maintain. They also scrape across ridges or unevenness in
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`the field and incorporate soil into the hay.
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`49. Rotary rakes originated in Europe to handle the heavy, wet grasses
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`that are harvested there. Some twin rotor rakes move hay toward the center
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`forming a single merged windrow, while others have identical rotors on both sides
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`so that all hay is moved in the same direction, moving hay to the side of the
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`machine, rather than the center, so that when the next pass is made, another merged
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`windrow is laid beside the first.
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`50. Rotary rakes are PTO or hydraulically driven so that tines can be
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`adjusted to operate above the ground thereby minimizing soil and stone
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`contamination of the windrow. Rotary rakes speed hay drying by making fluffy,
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`light and uniform windrows that dry faster. When operating, the correct
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`combination of tractor gear and engine speed must be found so that all forage is
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`swept into the windrow, but the rotor is not turning so fast that leaves are battered
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`from the stem. Dry matter losses of 8% have been reported from rotary rakes.
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`51. Wheel rakes are the lowest cost rakes because individual wheels are
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`ground driven and no powertrain is required. Higher end wheel rakes have wheels
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`mounted in front of the frame to handle larger crop volumes and have hydraulic
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`controls for folding and width adjustment. Better wheel rakes have larger diameter
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`wheels with stiffer teeth and larger overhead frames to accommodate these larger
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`wheels. All wheel rakes have springs whose tension can be used to adjust the float
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`of wheels. If wheel float is too light some crop is left behind but if too heavy, tooth
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`wear is increased and more soil and stones are included in the windrow. Generally
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`wheels should have about 20 lbs pressure (or slightly more with a windscreen).
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`Dry matter losses of 3.5 to 9% have been reported from wheel rakes (Digman,
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`2013).
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`52. Tedders break up a windrow that has become dense and will not dry
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`properly. Tedding should be done in the morning after the dew is off, but while the
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`hay is still tough. Tedders are recommended for grass hay which tends to settle into
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`a mat that dries very slowly. They are not recommended for alfalfa hay which
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`should dry adequately if put into a wide swath (covering at least 70% of the cut
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`area). If done when the hay moisture content is above 50%, leaf losses can range
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`from 2-3% for grass and 4 to 8% for alfalfa. One can lose up to 15% of dry matter
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`when alfalfa hay is tedded at lower moisture contents (Savoie, 1987).
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`53. A windrow inverter turns windrows over to expose wetter material at
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`the bottom of the windrow. This machine is not likely to be of benefit if one starts
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`with a wide swath but will increase drying by 0 to 4 hours (with associated dry
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`matter loss) if one began with a windrow. Inverting is a gentle hay handling
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`process and has lower losses than raking.
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`54. Mergers pick up swaths or windrows and move crop with a conveyor
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`to place forage into a single windrow. While the most expensive, they also result in
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`lower forage ash content and leaf loss than when hay is raked. Due to expense
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`(generally 3 to 4 times more than rakes) use of these items is limited to custom
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`harvesters and farms with large acreage.
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`
`
`V.
`
`Important Considerations During Forage Harvesting
`55.
`
`In this section I describe some important considerations when
`
`harvesting forage.
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`56. Forage should be mown and harvested with minimal dirt
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`contamination. This is estimated by the ash (mineral remaining after burning)
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`content of the forage. Forage plants have 4 to 8% minerals inside; any additional
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`ash is soil (dirt) contamination. Data suggests that many farmers are adding 4% or
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`more dirt to the forage when harvesting it (Undersander, 2004b). The goal should
`
`be to keep dirt contamination to 2% or less. This can be done:
`
`i) By using disc mowers with flat blades rather than the angled blades
`
`which create a suction during operation and pick up dry soil.
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`ii) Placing forage into a wide swath after mowing to keep the forage on top
`
`of stubble rather than laying on the ground.
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`iii) Raking so tines minimally touch the ground rather than digging into the
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`soil. This also reduces wear on the rake tines.
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`iv) Using a merger which picks up forage and moves it horizontally by a
`
`conveyer rather than raking along the ground.
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`57. Forage should initially be placed in a wide swath to facilitate rapid
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`initial drying to lose the first 15% of moisture, which slows plant resp