This is the time of year when prescribed burning happens around Kansas. The practice helps preserve native grasslands. But, recently, concerns have been raised about the impact on air quality. KSU's Zifei Liu has been researching the make up and movement of the smoke.

He advises pasture managers to use a specially-designed on-line tool as a guideline for burning with minimal impact on air quality. It can be found at www.ksfire.org.