Cattle producers aren't immune to nitrogen loss in pastures, according to Dirk Philipp, assistant professor for University of Arkansas System Division of Agriculture. Philipp says nitrogen is actually the most important and most costly plant nutrients, especially for cattle pastures.
Step one, Philipp says, is understanding the nitrogen cycle. Then producers can move on to evaluating the state of nitrogen in pastures and mitigating issues.
“Nitrogen compounds have to be converted to ammonium or nitrate to become useable by plants,” Philipp explains. For the conversion to happen, soil microbes convert urea to carbon dioxide and ammonia, then to nitrates, which the plants use.
But, he says, microbes can only thrive in certain conditions, and without the microbes, conversion is limited.
“Testing your soil for an optimal pH, for example, will allow you to keep these beneficial bacteria well-functioning,” says Philipp. “These microbes can also help keep nitrates from leaching out of your fields by incorporating excess nitrates into soil organic matter.”
Cattle play a big part in the nitrogen cycle, too, meaning that producers' proper management can facilitate the participation of cattle.
“In your pasture, do cattle leave urine and manure all over the place? If they don’t your field can lose nitrogen,” Philipp says.
Philipp adds that there are six tips for managing and improving the nitrogen cycle in pastures:
1. Maintaining a ground cover
2. Maintaining appropriate stocking rates
3. Use strip grazing, rotational stocking or methods that encourage manure distribution
4. Move water tanks, feed bunks and hay rings frequently
5. Maintain a record of soil fertility tests and watch out for nutrient deficiencies, which limit plant growth and nitrogen utilization
6. Monitor nitrogen fertilizers, which come with different percentage of nitrogen that affect the calculation of cost-effectiveness.
Source: University of Arkansas