Cut at time when quality high Low respiratory losses. Low leaf losses. Cut at time when quality high Low respiratory losses

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1 Cut at time when quality high Dr. Dan Undersander University of Wisconsin Low leaf losses 4% fat corrected milk (lb/day) Prebloom Early bloom Mid bloom Full bloom Alfalfa maturity stage % grain in ration 20% 37% 54% From Kawas et al., 1989 Component Mean Crude Protein, % DM Acid Detergent Fiber, % DM 0.36 Neutral Detergent Fiber, % DM 0.43 Neutral Detergent Fiber Digestibility, % NDF RFV, points -2.9 RFQ, points -3.6 Source: Undersander, 2009 unpublished Take first cutting by plant height Measure from soil surface. Measure to top of stem tip, not tip of highest leaflet. Cut at time when quality high Respiration breakdowns starch and sugars gives off CO 2 Estimates are made at 4 to 5 locations in a field. The tallest stem may not be the most advanced in maturity. 1

2 Nonfiberous Carbohydrate (NFC) is starch and sugars Nonfibrous Carbohydrate, % of DM Figure 1 Effect of nonfiberous carbohydrate content (NFC) on RFQ y = x R² = Relative Forage Quality Faster drying Higher forage quality Narrow windrow Need to dry off first 15% moisture as quickly as possible Wide Swath Legumes have 10 times more stomata than grasses Upper and lower epidermis is heavily coated with wax conserves water protects surface cells Stomatal opennings Sequence of Drying Forages Respiration continues after cutting until plants dries below 60% water 80% Stomatal openings Breakdown of starch and sugars Moisture 60% Conditioning Weather regulated Osmotic & Cell forces Carbon dioxide 20% Time 2 8% of Dry Matter loss 11 2

3 Table 1. Losses Due to Respiration Dry Matter Loss 2% 4% 8% Economic Loss ($/t) Hay value $181/t $4.78 $9.56 $19.12 Table 1. Losses Due to Respiration Dry Matter Loss 2% 4% 8% Economic Loss ($/t) Hay value $181/t $3.62 $7.24 $14.48 Forage Quality Loss from 4% sugar/starch loss ADF, % NDF, % RFQ Value, $/t $ Forage quality if lose 4% dry matter of starch/sugars $ Prices from Midwest Hay Market Report, Jan 24, 2016 $-57 Higher forage quality Increased yield Need to cut 3 to 5 days earlier to make up for increased fiber due to NFC loss Lose 160 to 200 lb/acre/day Higher forage quality Increased yield - cut need to cut earlier for NFC loss Increased yield of next cutting Less wheel traffic damage Quicker irrigation Traffic No Traffic Flail/impellers Intermeshing Rolls 3

4 Flail conditioners have 2 to 3 % higher field losses with alfalfa. Stems The loss is all leaves so forage quality is significantly reduced. Leaves 19 Begin with wide swath (>70% of cut area). Measure clearance where Crimp or smallest clearance occurs Conditioning necessary for hay not haylage. Condition alfalfa & alfalfa/grass mixtures with roller conditioner. Rake/merge with minimal ground contact to reduce dirt in forage. Additional tedding often necessary for grasses Cut at time when quality high Leaves higher in quality than stems Low leaf losses Leaves 15 to 20% NDF Stems 60 to 70% NDF Leaf Percentage Figure 2 Effect of leaf percentage on RFQ y = 0.515x R² = Relative Forage Quality 4

5 Machine adjustments and operating speed have largest effect Adding moisture at baling to keep leaves attached to stems Cut at time when quality high Low leaf losses 5

6 Depends on heat transfer conditions. Can bale without spoilage at higher moisture content if: Cooler air temperatures (e.g. fall vs summer) Smaller bale less self insulation Single bale vs stack some growers let bales sweat for a couple weeks then stack. TDN = dnfc + dcp+ 2.25*FA + dndf - 7 Change, Percentage Units 6 4 Dig NDF 2 0 Dig CP -2-4 Dig NFC TDN -12 Heating Degree Days > 86F *Hay preservative additives not needed for baleage Possible Preservatives Ammonia Urea Inoculants Propionic acid Acetic acid Buffered acids Acid salts Ethoxyquin Note: Ammonia recommended only for grass, not alfalfa Propionic Acid Required (lb/t) Propionic acid needed to preserve hay treat bales > 1500 lb treat bales > 200 lb treat small square bales Moisture Content of Hay (%) Can wrap bales at any moisture between 20 and 70% Below 50% moisture - oxygen exclusion Above 50% moisture both oxygen exclusion and fermentation with acid production Less spoilage on feedout a dye sprayer marking system provides a simple, practical method for visually identifying areas of high moisture hay in bales. Harvest Tec 6

7 Cutting forage for hay/haylage Higher initial machinery cost Higher energy requirement Stones cause knife damage Cutting forage for hay/haylage Higher initial cost Higher energy requirement Stones cause knife damage Greater bale density Better feed intake Better animal gain Less feeding loss NIR from Chopper Bale quality Time Mowing Early in the day (eastern U.S.) Early in the afternoon (western U.S.) Form into spread (wide) swath Rake or ted at 40% to 50% moisture Bale at 18% to 20% moisture, small square 16% moisture, medium square or round bale 14% moisture, large square or round bale Use buffered propionic acid or plastic wrap if wetter Store hay off ground and under cover fyi.uwex.edu/forage UW Publications Learning Store learningstore.uwex.edu Source: Pitt, R.E