Do prairie grasses really use their deep roots to access moisture in times of drought?

[Mike Morris]

Maybe not, according to this article from the Prairie Ecologist. "In fact, they may not use them to draw moisture at all." My mind is blown by this article, which is now a couple years old (but I just came across it).

Does anyone know more about this? And if those deep roots aren't drawing moisture, what the heck are they doing down there?