Winnowing uses the wind or blowing air to remove the husk from grains. 

Winnowing is the method of separating lighter particles (husk) from heavier components (grain seeds) with the help of wind or blowing air. In the process, the mixture is made to fall from a height and then due to the wind the lighter particle is carried away by the wind and the heavier particles are collected at the bottom. Thus, the driving force behind winnowing is wind or blowing air. Hence, the given statement is TRUE.