Edward Twidwell | 8/7/2009 7:58:43 PM
Ed Twidwell, Extension Specialist
Hay varies in quality more than any other field crop. Special attention should be given to the production of good-quality hay because animal performance is directly related to hay quality. Making good-quality hay in the Gulf South is not an easy task. Information presented in this publication provides some production recommendations for making good-quality grass hay.
Soil Test and Fertilize
Soil testing is strongly encouraged to determine lime and fertilizer needs. It is recommended to break fields into 10-to-15-acre blocks. From each block, collect soil from 10 to 15 places at random. Proper collection depth is the top 6 inches of soil. Place this soil in a clean, plastic bucket. Thoroughly mix the soil and remove about one pint for analysis. Send this sample to a Soil Testing Lab for analysis.
High-yielding hay removes large amounts of nutrients. One ton of hybrid bermudagrass hay removes approximately:
45 pounds of nitrogen (N)
12 pounds of phosphorus (P2O5)
50 pounds of potash (K20)
6 pounds of sulfur (S)
The amount of fertilizer to be applied is determined by the yield goal. For a “ball park” estimate of fertilizer needs, multiply the nutrient needs listed above by the desired yield goal. For example, a 4-ton yield goal would require about 180 pounds of N, 48 pounds of phosphorus, 200 pounds of potash and 24 pounds of sulfur. A 2-ton yield goal would require only ½ of this amount of fertilizer. Taking soil samples once every two years and following fertilizer recommendations will help producers fine-tune their hay production program.
Harvest at the Correct Stage of Maturity
Of all the factors that affect hay quality, the growth stage when it is harvested usually has the largest effect. As grasses mature from the vegetative to the reproductive (seed) stage, they become higher in fiber and lower in crude protein, digestibility and palatability. For optimum quality, it is generally recommended to harvest bermudagrass at a 15- to 18-inch height for the first cutting and then about every four weeks thereafter. Bahiagrass can be harvested at longer time intervals between cuttings. Winter annual grasses such as ryegrass should be harvested at the boot to early-heading stage.
Weed and Pest Control
The presence of weeds with quality lower than the forage being produced reduces the overall quality of the forage and weed mixture. Weeds must be controlled if optimum quality is the goal. Most broadleaf weeds can be controlled with herbicides. Controlling grassy weeds in bermudagrass is more difficult due to the lack of selective herbicides. Damage from insects and diseases tend to lower the quality of forages, especially if they attack leaves of the forage plants. Producers should monitor their stands frequently for the presence of fall armyworms during the summer months.
Curing and Handling Conditions
After mowing, poor weather and handling conditions can lower hay quality. Rain can cause leaf loss and nutrient leaching from plants during curing. Raking dry, brittle hay can cause excessive leaf loss. The goal of the hay producer is to take forage plants from an initial moisture content of 70-80% down to about 15% for safe baling and storage. Bale temperature should not exceed 150o or excessive nutrient loss or possible ignition could occur. Rapid curing and baling conserves leaves, nutrients, color, palatability and other quality factors.
Research has shown a 25-30% dry matter and quality loss for hay stored uncovered outside compared to hay stored in a barn or under a tarp. Hay should be stored on pallets or crushed rock to decrease the amount of hay-to-soil contact and reduce losses at the bottoms of the bales. Select a storage site that is gently sloping and well-drained.
The most reliable way to determine hay quality is through chemical analysis. The Forage Testing Laboratory at the LSU AgCenter’s Southeast Research Station can analyze hay samples for crude protein, TDN and other nutrients. Producers need to obtain a representative sample of hay, which can be obtained using a hay probe. Take samples from about 10-15 bales, mix them together and send to the lab for analysis. You should receive your test results back in about one week. These results can be used to assess hay quality and to determine type and amount of supplementation needed for the desired level of animal production.
For more information on forage production and management, go to the LSU AgCenter Web site.