Rhubarb
If there is some garden bed the chickens can scratch up, then they will scratch it up. It's as inevitable as taxes. My new rhubarb plots, placed so they would have good drainage were just starting to look good with new growth. Then.. chickens. There's a saying about a watched plot never spoiling, and it's true, because the chickens come when you're not watching.
Here are two shots before chicken.
And a shot after, with netting in place. That's some of the more affordable netting, at $3 for 1.5m x 6m I think. I'll have to lift it up as a fence when the rhubarb gets bigger.