Hay Moisture Probe

Rate of Respiration Loss Depends on Internal Crop Moisture and Air Temperature 80 70 60 50 40 30 20 Moisture level, % 0.40 0.35 0.30 0.25 0.20 0.15 0.10 DM losses, (% DM/hour) 95° F 77° F

Drying Times Vary 80 60 40 Moisture (%) 20 0 1 2 3 4 5 6 Days 0 1 2 3 4 5 6 Days 80 60 40 20 Moisture (%) Good Drying Conditions Poor Drying Conditions

Conditioner Drying Rates Alfalfa Grass

The Effect of Conditioner on the Relative Drying Rate of Alfalfa Not-tedded Tedded ------ (difference from control) ----- No conditioner ** +17% Rubber crimping roll +18% +48% Steel flail +24% +50% Plastic V-flail +14% +35% Alfalfa Grass

Night-Time Moisture Fluctuations 0 1 2 3 4 5 6 Days 80 60 40 20 Moisture (%) Good Drying Conditions Poor Drying Conditions

The Effect of Relative Humidity 30 40 50 60 70 80 90 Relative Humidity, % 40 30 20 10 Equilibrium Moisture (%) 77° F 95° F

Hay Moisture Probe Contacts

Accuracy of Various Hay Moisture Probes – 4th cutting Bermudagrass

Shinners, University of Wisconsin Moisture distribution of mixed grass-legume round bales stored on the ground % Moisture Twine Wrapped Net Wrapped Moisture differences at 4 inches due to wrap appear to be greater with predominately alfalfa bales as compared with grass bales. Wisconsin researchers noted little change in bale core nutrient profiles due to wrap. This is due to low moisture (less than 20%) in the core of bales studied. Change in nutrient composition of the outer portion of the bales tends to be higher with twine wrapping as compared to net wrapping. (Reference: Shinners et al., 2002 ASAE International meeting, paper 021067) Shinners, University of Wisconsin

Shinners, University of Wisconsin Moisture distribution of mixed grass-legume round bales stored on the ground vs. elevated % Moisture Twine Wrapped On a Pallet Moisture differences at 4 inches due to wrap appear to be greater with predominately alfalfa bales as compared with grass bales. Wisconsin researchers noted little change in bale core nutrient profiles due to wrap. This is due to low moisture (less than 20%) in the core of bales studied. Change in nutrient composition of the outer portion of the bales tends to be higher with twine wrapping as compared to net wrapping. (Reference: Shinners et al., 2002 ASAE International meeting, paper 021067) Shinners, University of Wisconsin

Every little bit helps!

If it has to be outside… Store bales with N/S orientation Don’t store under trees Make dense bales Shed water better Elevate the bales

Heat Damage to Crude Protein DM Intake Useable Protein Heat-Damaged Protein Protein Heat

Bale at the Right Moisture Ideal Range, 50-65% Moisture 70% 40% Moisture Potential for Spoilage or Toxicosis (Clostridial, Listeriosis) Poor Fermentation Rule of thumb: bale when the forage is no longer wet enough to wring juice out of a handful.

The Effect of Rain on Tall Fescue Hay No Rain Rain Damage Intake, % of b.w. 2.10 1.92 NDF, % 68.1 76.0 Digestibility, % 63.2 59.7 Turner et al., 2003

The Effect of Rainfall on DM Loss Rainfall, in. Scarbrough et al., 2005

Crop Moisture Lessens Rain Damage on Bermudagrass DM Loss, % 76% Moisture, Not Significant. Rainfall, in. Scarbrough et al., 2005

Crop Moisture Lessens Rain Damage on Bermudagrass NDF, % 76% Moisture, Not Significant. Rainfall, in. Scarbrough et al., 2005

Is the risk of rain damage overblown? every day after 4 wk = ~0.5% points drop in TDN. 1 wk delay to avoid ½” rain = ~3.5% drop in TDN A ½” rain = ~1.0% drop in TDN

Components of Curing Losses Rainfall and leaching Respiration

Conditioning Systems

“My Buddy, Ted” Increase hay-drying rates by 20-40% (~ 0.5 – 1 day) DM Loss: Grasses (<3%) Legumes (7-10% +) Breaks up clumps & distributes the crop over the entire area. Increased sun Fluffed for better air movement Initial tedding: w/in 2-4 hrs (clumps break better) Additional tedding? May be necessary for grass, probable for alfalfa

Hay Curing Management Conditioner? YES. Wide or narrow swath? Wide as possible When to mow? Early as possible Ted it? YES, but only when damp and toward the end of when the dew is on. Avoid tedding legumes when > 50% moisture Moisture at raking? 35-40% for legumes 20-25% for grass/legume mixes ~<20% for bermudagrass Moisture at baling? Small square = 18%, Round bales = 15%

Typical Hay Storage Losses Twine Net wrap (% of dry weight) Pole barn 2-5% Hoop structure Tarp 5-10% 5-8% Stack pad, covered stack uncovered stack 15-40% 10-30% Plastic wrap N/A Outside on ground, well-drained 20-40% poor drainage/shaded 30-60% 30-45%

Losses During Storage Even when hay is baled at the target moisture (15% moisture for round bales; 18% for squares), the forage will go through a “sweat” for 2-3 wks. Moisture is driven off, heat is given off, and DM dec. A 1% decrease in moisture ≈ 1% decrease in DM Moisture tends to equilibrate at 12% during storage 20% Moisture 12% Moisture CO2 H2O + 1000 lbs DM 920 lbs DM

Bale Moisture Affects Bale Temp Days 0 10 20 30 40 75 100 125 150 Temperature, °F 17% Moisture 25% Moisture 33% Moisture Small Squares Coblentz et al., 2000. Crop Sci.

HEAT Carbohydrates (sugars) Aspergillus Penicillium O2 + H2O CO2 Mold Spores Aspergillus Penicillium O2 + H2O CO2 Carbohydrates (sugars)

Risk of Heat Damage and Bale Moisture

Bale Temperature & Fire Risk