U.S. Department of Agriculture

A map forecasts rangeland production if precipitation in these Plains counties is near-normal.

Ranchers and land managers have a new tool to help predict the quality of grazing land.

Come spring, livestock ranchers in the Great Plains region take a look at where the best land for grazing will be.

Now, a collaboration with nationally funded researchers is using 30 years of data to create the first ever “Grass-Cast.”

The team uses historical data for counties, plus satellite images and weather forecasts to create a map of where to most likely find good vegetation growth. The data coming in compiles measurements from the on the ground and in the sky. 

University of Arizona Assistant Professor Bill Smith crunches the satellite statistics that make the maps.

“With satellite data, we’re really able to look at these rangelands on a near daily basis and look at them across different areas of the electromagnetic spectrum, in a way that we can provide a lot of useful information,” Smith said.

Arizona data isn’t included yet, because current satellite technology measures a wavelength of light that grasses put out as they photosynthesize. In Arizona, it is more difficult to measure that wavelength because the climate and the contrast with the color of the soil. But Smith hopes by using new satellite technology that measures a different wavelength to measure, ranchers here will have a new option for their 'Grass Cast' soon.