Medicated chick feed contains antibiotics. (Wrong.)
Home flocks don't need to be immunized for Marek's. (Wrong.)
Free range is healthier (Wrong. Exposure to wild birds can mean parasites and diseases and here it means they will likely be eaten by predators. I'm on a local chicken list where it seems October has been "my chicken was eaten by a hawk month.")
Give them lots of greens and snacks. (Imbalances the laying ration and puts them at risk for deficiencies - no more treats and greens than they can clean up in fifteen minutes per day.)
Heritage breeds lay longer than hybrids. (Wrong.)
Heritage breeds are "better". (Maybe if you're showing; not if what you want is high egg production or an economical meat bird unless you find a good utility strain.)
Start with a variety of different breeds and decide what you like. (Wrong. When you're getting chickens, decide what you want to do with them. If you want eggs, I recommend that beginners go with utility Barred Rocks or Black Stars for brown eggs, and California Grays for white eggs. These breeds are gentle, quiet, easy to handle, and very hardy. I have had too many people looking for a home for a Brown Leghorn that acted like a Leghorn and was flighty, noisy, and avoided people, and too many other people who want to get rid of exotic breeds that weren't productive layers.)
Clean your coop and sanitize all of the dishes every day. (Forget it. I deep litter the coop, clean the trays that go under the roost once a week and add more wood chips to them, clean the dishes when they need it, rinse out the waterer every day or two, and rake the yard with Dolomite whenever it gets smelly. I also toss down a layer of coarse cedar chips in the yard in the summer which keeps odors down.)
Cedar is toxic to chickens. (Well, commercial pastured poultry operators use it, and so do commercial yarded poultry operations. Oregon State University's Animal Science Department says it is perfectly fine. If you think cedar is causing your problem, check for inadequate ventilation and wet litter. )
Chickens can get all of the nutrients they need by free ranging. (Not unless they are ranging in a barn yard where lots of nice maggots are growing in the other animals waste, there is lots of spilled grain, and plenty of mice to eat. Chickens love to eat mice in old fashioned barns.)
Chickens are vegetarians and can live on grains. (Chickens love meat, including other chickens, mice, insects, etc. They also like grains and greens and vegetables and some fruits. Chickens are omnivorous and inclined to eat anything that can run away fast enough.)
And the biggest omission that no one tells beginners - different breeds of chickens have very different temperaments. Some of those pretty living lawn ornaments will spend their entire lives avoiding you or flying into the neighbors' yards and annoying them, and some of them will make as much noise as a banshee.
