by Amanda Smith, Hoard's Dairyman Associate Editor
Early and frequent harvesting at the bud stage to yield dairy quality alfalfa comes at a cost to the plant, noted Dan Undersander with the University of Wisconsin at a Professional Dairy Producers of Wisconsin Feed and Nutrition Conference. Harvesting at this immature stage robs the root and crown of its stored products and leaves the plant in a weakened state. Each successive premature cutting compounds these detrimental effects.
Fall growth this year was reduced due to a dry August and early September. With drought stressed alfalfa, stands under 10 inches will yield half a ton per acre or less. Stands over 10 inches and flowering will have a better yield but should only be harvested if it is economic to do so. Due to the presence of additional leafy material, you can let the plants approach 100 percent bloom before harvest.
Additionally, noted Undersander, moisture stressed alfalfa should be mowed at the normal cutting height – raising the cutting height has no advantage, it simply reduces harvested yields. When harvesting dairy quality hay, he stressed that in a three to four cut system at least one cutting should go to 10 percent bloom to redevelop the stand. With five to six cuttings, two stands will ideally be allowed to reach 10 percent bloom.
He also noted that drought stressed new seedings should not have been harvested during the season. They may be harvested though in late August if adequate growth is present to justify harvest. A late fall cutting may also be taken. With a late fall cutting it is important to cut ahead of a killing frost to minimize potential regrowth.
Undersander also touched on a few strategies to help prepare for 2013:
- Take feed inventories – determine what you have, how long it will last and what will need to be purchased.
- Make culling decisions early – this leaves extra feed for the cows that stay in your herd.
- Fertilize alfalfa with potassium to ensure that soil fertility is at an optimum level.
- Apply sulfur at 15 pounds per acre if fertilizing this fall to prepare for the first cutting next spring.
- Prepare to fertilize alfalfa after first cutting with an additional 10 to 15 pounds of sulfur per acre.
- Maximize your pasture use – fertilize and allocate forage using a paddock system. When cattle are given access to the entire pasture at once, they will utilize approximately 40 percent of the forage. When this is broken into paddocks, utilization can rise 20 to 30 percent.