Julie Walker: Putting up high-quality hay
June 8, 2012
The days of cutting hay on an International H or M tractor with a sickle mower are long gone for most, says Julie Walker, South Dakota State University (SDSU) Extension Beef Specialist.
“It seemed like a field took forever to finish cutting. I clearly remember the day that Dad purchased a 12-foot mower with conditioner. Boy could you lay down the hay with that piece of equipment,” Walker said, of her childhood growing up on a farm in Minnesota. “Needless to say, hay equipment has improved over the last few decades.”
Although equipment has improved, there are still many decisions Walker says producers need to make to ensure hay quality is adequate. The decisions producers make as managers of forage resources will hopefully reduce the amount of supplementation that will be required to meet the animal nutrient requirements.
“Many producers would say quality hay is green in color, free of mold and weeds, has a high portion of leaves and it was put up without rain on it,” said Walker, adding that although these are good indicators of high-quality hay, they don’t tell producers anything about the nutritional content of the forage.
Sampling is the best way to understand the nutritional content of forage, Walker says.
“Producers need to sample the hay once it is in the stack and send the sample to a lab for nutritional analysis. This is essential to understanding its true quality,” she said.
What are the best management practices that should be considered to improve the odds of getting a stack of high-quality hay?
To answer this question, Walker first asks producers if they go for quantity, or quality?
“Forage has the highest digestibility in the vegetative stage, and is less digestible at seed stage. As the plant matures from vegetative to seed stage, the digestibility decreases and the amount of biomass available for harvest increases,” she said.
Figure 1 shows the maximum yield of digestive dry matter. For grasses, the maximum yield of digestive dry matter would be obtained at the late boot to early head stage of maturity and for legumes, the mid-to late-bud stage of maturity is best.
Research has shown that forage cut at or near sundown has higher energy compared to morning.
“This is a natural physiological process in plants wherein concentrations of soluble carbohydrates and other highly-digestible nutrients are highest after a full day of sunshine and photosynthesis,” Walker said.
She adds that tall enough stubble height should be left to aid in drying, which also improves pickup performance.
“However, too high of stubble height will reduce yields,” she said.
Correct hay curing (drying) is the next step. Walker says various factors can reduce hay quality during the drying phase, these include: respiration, weather and loss of leaves. Some tips she shares to speed up curing include: using a mower conditioner speeds drying by opening the waxy layer surrounding the stems in legumes; large and/or coarse stemmed forages have shown faster drying when conditioned. Wider swaths also allow for faster drying. Raking should be avoided if possible when the forage moisture is less than 40 percent.
Hay desiccants are used to reduce the amount of time required for hay drying. The commonly used hay desiccants are potassium carbonate or sodium carbonate, which are sprayed onto the hay during the cutting phase.
Walker says hay desiccants are effective on alfalfa, clover and birdsfoot trefoil to remove the moisture-conserving waxy cutin layer of the plant, however, they are ineffective on grasses such as orchardgrass, timothy and bromegrass.
“When considering using hay desiccants remember to include the cost of the chemical as well as the sprayer for application,” she said.
Walker adds that reducing leaf loss during the baling phase is key to maintaining quality.
“Baling at moisture content above 15 percent has less leaf loss than below 15 percent. Typical moisture content of the bales needs to be below 18 to 20 percent to prevent mold growth,” she said. “When putting up hay with higher moisture content other management steps need to be implemented to ensure maintaining hay quality as well as reducing the risk of fire.”
Feed costs are a large portion of annual cow costs, so managing the forage resource to get a quality hay product, which will reduce the need for additional supplementation, can ultimately reduce the feed bill. For more information visit, http://www.igrow.org.
– SDSU Extension