Current Progressive Cattle digital edition
advertisement

Forage legumes provide many benefits to beef cattle operations in terms of their quality, productivity and ability to contribute nitrogen back to the system. In times of increased fertility input costs, forage legumes are generally revisited as an option to help provide nitrogen in forage systems. However, it is important to understand how forage legumes work in our Southeastern systems, especially when most forage legumes are grown in combination with grasses during the grazing season.

Legumes have a mutually beneficial relationship with the bacteria rhizobium. These bacteria infect legume root hairs, forming small nodules near the point of root elongation, or root nodes. These bacteria help remove nitrogen gas from the atmosphere and convert it to a plant-usable form. This process is referred to as nitrogen fixation. Biologically fixed nitrogen is available to the legume once the roots have been infected and nodulated. A good way to know if legumes in your pasture are fixing nitrogen is to dig up a plant with roots attached and physically cut open one of the nodules on the root system. If the color inside of the node is pinkish-red, then nitrogen is actively being fixed by the plant.

Legumes can help provide a source of nitrogen for grasses in the system through a “give and take” relationship. As legumes are defoliated, either by grazing or mowing, this causes the roots to die back, releasing some nitrogen for surrounding plants. Aboveground legume leaf litter, or leaves that have fallen from plants over time, can degrade and go back to the soil. Grazing animals also recycle nutrients back to the soil while grazing mixed legume-grass pastures, which represents another source of nutrient return.

In other words, nitrogen fixed by forage legumes takes some time to become available to surrounding grass plants in a stand. It is generally recommended that legumes make up at least 30% of the pasture for no nitrogen to be applied. It is important that legume plants are well distributed across the pasture to see a more uniform response. Annual use of legumes in pastures will help build soil quality, increase plant diversity in pastures and provide a high plane of nutrition in beef cattle grazing systems.  end mark

Kim Mullenix
  • Kim Mullenix

  • Extension Beef Specialist/Associate Professor
  • Auburn University
  • Email Kim Mullenix

In the USDA National Agricultural Statistics Service (NASS) semiannual Cattle report released on Jan. 31, the total number of cattle and calves on Jan. 1, 2022, was estimated at 91.902 million head – 2%, or nearly 1.888 million head lower than the previous year.

Read more ...

The U.S. will no longer receive Russian energy exports, President Joe Biden announced March 8. The ban on Russian oil, liquefied natural gas and coal is the latest in several retaliatory sanctions against Russian international commerce following the invasion of Ukraine in late February.

Read more ...

In the weeks following Russia’s invasion of Ukraine on Feb. 24, the prices of everything from food and gasoline to wheat, corn and other feedstuffs have reacted with extreme volatility.

Read more ...

Last week, Elliott Dennis discussed the relationship between corn price and feeder cattle placement weights and the likelihood that the industry will continue to place lighter weight cattle while corn prices remain high.

Read more ...