Research that takes a closer look on the impact of global warming on grasslands says they could actually become more productive.

But the study warns that ranchers and farmers would have to make major changes to adapt.

The authors say the prairies of southern Canada and the U.S. could see an overall increase of about 18 per cent in the amount of grass cover.

The increase would happen in the spring and fall.

The study says mid-summer grasslands would be a lot less productive.

That means ranchers could not be able to count on their animals getting enough food on browner, drier pastures.

The authors say farmers would also have to change their practices.