Gearing Up Your Summer Forage Production
Amy: Rocky with hay production at full swing and plenty of rain to keep pastures growing, what is the first thing that producer should do to maximize production and efficiency?
Rocky: The first thing will be to take a soil sample to know the nutrient status of the pastures and hay fields. That will allow providing the necessary nutrients, especially in hay fields where larger quantities of nutrients are removed in the hay and exported to other parts of the farm during hay feeding season or off the farm when hay is being sold. Something that is very common in forage systems in MS is that soil pH and potassium levels are usually low due to mismanagement. In this case liming should be done first to make sure that root systems are strong for nutrient uptake. Lime is the cheapest source of fertilizer that a forage producer can apply before developing a more comprehensive nutrient management program.
Amy: You mentioned liming, there is a buzz for the use of liquid lime. Is liquid lime providing the soil and economic benefit?
Rocky: Soil pH is the greatest variable that directly influences chemical and biological functions in the soil. Before selecting a liming agent, it is important to know how much active ingredient or relative neutralizing power you are paying for and determine the economic feasibility of the selected product. Liquid lime usually has a high relative neutralizing value (RNV) greater than 90%. However, due to lime solubility in water, you might be getting an application of 0.5 ton of time per ton of liquid lime applied since 50% is water. Even when applied at the equivalent rates of agricultural or pelletized lime, liquid lime is only effective for rapid pH adjustments and not a long-term soil pH stabilization. Although the fine material in the liquid lime can have a greater neutralizing effect on a per pound basis, the faster reaction time will also have a short life of actual neutralizing capabilities. Therefore, the liquid lime might only be effective at neutralizing acidity from a few weeks to few months depending on rate of application.
Amy: What is the best management practices when it comes to hay production to balance yield and nutritive value?
Rocky: Forage and livestock producers focus too much on yield production rather than balancing yield and nutritive value that could help minimize any commodity supplementation during the winter. There are two factors that can affect hay production in the summer time and those are fertilization especially nitrogen and maturity. In a hay production system, a producer should apply at least 50 actual units of nitrogen per acre per cut of hay. Applying all the nitrogen at the beginning of the season will result in nitrogen loss and yield reduction later in the season. Maturity is the major factor affecting nutritive value. Therefore, cutting hay in a 25 to 35 day interval depending on forage species and environmental conditions is important. The more mature the forage, the higher fiber content. This will affect nutrient availability, animal forage intake and forage digestibility in the rumen of the cow.
Amy: Due to the weather conditions that we face during the summer, are there any pests and diseases that producers should be scouting for in their fields?
Rocky: There are several pests that we need to be vigilant of in bermudagrass, those include bermudagrass stem maggot and armyworms. Armyworms can also affect summer annual grasses such as millets, forage sorghums, and sorghum-sudan grasses. These summer annual grasses can also be affected by the sugarcane aphid. We have seen an increase in leaf spot diseases in both bermudagrass and bahiagrass. These are usually related to wet conditions and low soil potassium making plants more susceptible. We have seen an increase in diseases in bahiagrass where large quantities of poultry litter have been applied without a soil test recommendation. Poultry litter can act as a sponge to retain water and the high phosphorus create the perfect conditions for fungal diseases to proliferate.
Amy: Weeds can also be a problematic issue in summer forage production, what approach should a producer take?
Rocky: There are several troublesome summer weeds such as foxtail, horse nettle, dogfennel, johnsongrass, smutgrass, vaseygrass among others that can reduce forage production. Producers want to implement a weed control management that can provide a broader control of weeds. Keep in mind that there is not a one herbicide fits all situation. It is important to scout the fields, determine weed populations and develop a control plan. Producers need to pay attention to replanting, grazing, and haying restrictions when using herbicides. For more information related to weed control, they can check Publication 1532 in the Mississippi State Extension Website and refer to the forage section.