1. Importance of Wide Swaths in Drying Hay and Haylage Dr. Dan Undersander University of Wisconsin

2. Dan Undersander-Agronomy © 2007 Standing alfalfa loses quality if not harvested Average rate of change is 5 points RFV or RFQ per day

3. Dan Undersander-Agronomy © 2007 Days without rain at La Crosse More chance to get hay or haylage harvested without rain if shorten drying time

4. Dan Undersander-Agronomy © 2007 Wide swath benefits Faster drying Higher forage quality

5. Dan Undersander-Agronomy © 2007 Phase I moisture moves along stem Primary moisture loss is through stomata Phase II Primary moisture loss from the stem surface Phase III Removes tightly held water below 45% Sequence of Drying Forages

6. Dan Undersander-Agronomy © 2007 20% Stomatal openings Conditioning Osmotic & Cell forces Time Moisture 70% Weather regulated Sequence of Drying Forages 80%

7. Dan Undersander-Agronomy © 2007 Legumes 10X more stomata than Grass Initial 15 to 20% water loss is through stomates in leaves

8. Dan Undersander-Agronomy © 2007 Stomata Openings Open in sunlight Shading closes Stomata 20 – 30% of water removed before stomata close Removes up to 30% of the water from the stem (grass)

9. Dan Undersander-Agronomy © 2007 Breakdown of starch and sugars Respiration continues after cutting until lose some water 2 – 8% of Dry Matter loss Each 1% DM loss is 1% less TDN! Carbon dioxide

10. Dan Undersander-Agronomy © 2007

11. Relative humidity inside windrow

12. Dan Undersander-Agronomy © 2007 Wide swath

13. Dan Undersander-Agronomy © 2007 Kilcer, 2003

14. Dan Undersander-Agronomy © 2007 Milk per acre increase with Wide Swath Kilcer, 2003

15. Dan Undersander-Agronomy © 2007

16. Mower-conditioner Swath Width Study (Windrow 33% and Swath 65% of Cutting Width)

17. Dan Undersander-Agronomy © 2007 Wisconsin Study Results (Herzmann, 2004) Moisture Content after six hours Width (percent of cutting width) Conditioning 1006533 No 63.5 64.569.5 Yes 57.063.066.5

18. Dan Undersander-Agronomy © 2007 Wisconsin Study Results (Herzmann, 2004) Moisture Content after six hours Width (percent of cutting width) Conditioning 1006533 No 63.5 64.569.5 Yes 57.063.066.5 Therefore conditioning not necessary for drying alfalfa to 65% moisture for haylage if using wide (>70% cut width). Conditioning necessary for narrow swath/windrow haylage and for hay.

19. Dan Undersander-Agronomy © 2007 Wisconsin Study Results (Herzmann, 2004) Moisture Content after six hours Width (percent of cutting width) Conditioning 1006533 No 63.5 64.569.5 Yes 57.063.066.5