Pasture and Forage Minute: Making a Drought Plan, Monitoring Forage Nitrates
Drought Planning for the Grazing Season
The start of the growing season is just a couple of months away and last year’s drought conditions across parts of Nebraska should inspire us to complete grazing and forage plans for the coming year. Depending on the local drought severity in 2021, it is not uncommon that there would be some carryover effects on grass production in 2022.
Within these plans, options for a possible drought are essential. A drought plan can have varying levels of detail and complexity and can be customized to fit the specific needs of your operation. Key considerations should include projected cattle numbers (or stocking rates), turnout dates, the possibility of an extended period of hay feeding, the level of utilization on pastures last year, possible culling and weaning strategies, and a pasture use sequence for multiple pasture rotations. In addition, some farmer and ranchers have the opportunity to use planted annual forages to increase grazing capacity or to provide extra hay. Sourcing seed for this possibility should begin soon.
Some plans place an emphasis on critical or trigger dates. These are dates where one evaluates their total local precipitation up to that date. On May 1, for example, one could determine their total spring precipitation and compare that to long-term averages for their area. If precipitation totals are significantly below the averages, that could trigger a choice of several possible management actions such as an extended period of feeding hay or culling of some livestock.
Remember that no two drought plans are exactly alike and should consider an individual ranch’s resources and local conditions.
While we always hope for the perfect amount of rain for the growing season, being prepared for droughty conditions can reduce the impact.
Don’t Risk Cattle with High Nitrates
Are you feeding cane, millet or oat hay, or maybe cornstalk bales to your cows this winter? If so, don’t let high nitrate levels kill your cows or cause abortions.
Nitrates occur naturally in all forages. At low levels, nitrates either are converted into microbial protein by bacteria in the rumen or they are excreted. But when nitrate concentrations get too high, they can cause issues.
When stress affects pasture and hay production, nitrates often reach potentially toxic levels. Some plants are more likely to be high in nitrates than others. Annual grasses like cane, millet, oats and even corn often have elevated nitrate levels. So do certain weeds like pigweed, kochia and lambsquarter. If your hay has lots of these weeds or is an annual grass, be alert to the potential for high nitrates.
That doesn’t mean these feeds always are toxic, nor does it mean that high-nitrate hay can’t be fed safely. But always test these feeds for nitrates in a lab before feeding, to determine how to feed them safely.
If we do have high nitrates, there are many ways to feed the hay safely. Diluting with grain or low nitrate forages is most common. Frequent, small meals that slowly increase the amount of nitrate fed helps cattle adapt to high nitrate hay.
Remember with this last approach that any time cattle go off feed then come back — like after a snowstorm or if a feeding was missed — they are more likely to consume more hay than normal. This raises the amount of nitrate consumed and can result in poisoning, even in an adapted herd.
Finally, make sure cattle have plenty of clean, low nitrate water at all times.
Nitrate concerns are nothing to sneeze at, but with the right tools, can be managed safely. Test hay you think may have an issue — especially annual grasses and hay with a high percentage of weeds. If tests come back high, plan to feed safely by dilution, or gradually increase the amount of the feed to adapt animals to it.