I made some wheat, complete with the little hairs. I've set up a particle system to use my wheat reference and the result is pretty good at first glance.
However, if I turn off phase randomization it pretty quickly becomes apparent that the hair system used on my object is all biased in one direction.
I haven't used any Tangent or Object Aligned particle velocity and my scene doesn't contain Wind.
This is an object that I approved of wholeheartedly before I prepped it for use within a particle system. (R X -90 and Apply Rotation)