Rod Heitschmidt, USDA's Fort Keogh Livestock and Range Research Laboratory in Miles City, MT, says producers don't have to wait until they're out of forage before making management decisions. Instead, Heitschmidt says producers can be proactive by monitoring precipitation early on during the growing season and making decisions based on historical data.
"Drought is quite normal in the Northern Great Plains, and historical precipitation probabilities can be a good indicator of years when drought will be likely," he says.
For instance, Heitschmidt says historical records show that a current year's forage production is primarily a function of April and May precipitation with June being less important than one would think.
Additionally, from evaluating more than 15 years of research from 15 different data sets, Heitschmidt says 70% of forage for the year is typically produced by June 1 in the Northern Great Plains and 90% is grown by July 1. He clarifies that there's no way to judge how much total forage will be produced, just that 90% of the total amount will be grown by early July.
Thus, by monitoring spring precipitation, Heitschmidt says producers in the Northern Great Plains can begin to make drought decisions by July 1.
Here's why. Heitschmidt says producers know whether their spring precipitation is below, near or above normal. Even if they get 1 in. of rain in July, it won't grow as much forage as 1 in. of precipitation in April. Therefore, if spring rainfall is below normal, he suggests producers should plan in early July to take positive action to reduce risk.
"Wean early or sell open cows," he suggests. "If you hang on until you're completely out of forage in October, you're putting yourself at risk."