Bracken is a genus of large, course ferns from the family Dennstaetiacae. Ferns are vascular plants that have alternating generations with large plants that produce spores and small plants that produce sex cells.
They have large and highly divided leaves and are found on all continents except Antarctica and in all environments apart from deserts. They also have immature varieties called fiddleheads.
image wikipedia
So can rabbits eat bracken at all?
Unfortunately, they cant eat it. Bracken is poisonous to rabbits and will harm them if they eat it. So steer clear of feeding it to bunnies.