New Maps From USDA Help Ranchers Find Greener Pastures

Jun 19, 2018

Each spring, ranchers across the Eastern Plains look at their land and ask an important question: How much green can they expect this season?

In this case, “green” refers not to money, but grass. And the U.S. Department of Agriculture recently launched a new tool to help cattlemen predict just how much they can look forward to.

The “Grass-Cast” is a digital map that combines seasonal precipitation forecasts with more than 30 years of historical data on weather and vegetation growth. Dannele Peck, director of the USDA’s Northern Plains Climate Hub, said ranchers rely on tools to predict grass growth.

“They know that during the upcoming summer they’re going to rely very heavily on these rangelands and how much grass grows out there to support their cattle herd,” she said.

Until recently, there have been few methods. Traditionally, ranchers have relied on regional precipitation forecasts, but Peck said that information doesn’t paint a clear picture for grass growth. Grass-Cast takes that it a step further by combining it with 30 years of historical data on weather and vegetation growth.

Peck, who named Grass-Cast and was involved in its development, said the idea came from a similar product that’s existed in Australia for the last 20 years.

“Let’s hand [ranchers] a forecast of the thing they actually care about — and that’s how much grass is going to grow out of their rangelands,” she said.  

Credit U.S. Department of Agriculture

Green grass quickly translates into how much money a rancher can earn. If they know how much they can feed their herd over the summer, they can make important decisions, like how many cattle they should sell to market in the spring. For example, if there’s a drought halfway into the summer, selling early can help ranchers get a better price at market.

“(If) all of the ranchers realize at the same time, ‘Uh oh, we’re gonna have a drought,’ and they all send a bunch of their cattle to the market, well, that would drive prices down,” she said.   

A collaboration between several government agencies, Colorado State University and the University of Arizona, Grass-Cast maps are updated every two weeks and can be consulted all summer long. Ranchers can go online to see maps of three different possible outcomes depending on precipitation levels: normal, below average and above average.

Peck is hopeful there’ll be a Grass-Cast service available for ranchers in the Southern Plains by next spring.

Follow Esther on Twitter: @estherhonig