(Note: this thread was split from the Home Cooking board at: http://chowhound.chow.com/topics/863485 In particular, it was a reply to this statement:
2) Understand that all beef is "grass fed". Beef steers all start out eating a diet of grass, hay, and sillage once they are weaned off of milk. In a quality operation a steer must be at least a "yearling" (12-18 months) before they are finished in the feed lot. Lesser operations hurry the process.
-- The Chowhound Team )
All beef is not grass fed. Grass fed if they're taken off pasture. All benefits of grass feeding are lost within short weeks of grain feeding. A grass fed label cannot be slapped on feedlot beef, even if the feedlot was only a matter of weeks.