Crop bound?

Hello SusieB,
Crop bound is when a hen has a solid mass of tangled food in her crop, usually long grass or similar.  Once the grass has been mown, your hens will keep it to a similar height - or less if they scratch it all out.
If your hens' crops are empty each morning, they are OK.  They would look very "blousy" on the right front of their chest if crop bound.
They tend not to eat what is bad for them, so don't worry about buttercups.  I think my girls leave the stuff alone.
Good luck.
cathangirl