Is Russian Knapweed safe for rabbits to graze?

I have posted on permies many times about my arch nemesis Russian Knapweed.  I hope people are nt getting sick of me harping on about it.  I am trying to deal with the weed in my large pastures by overseeding with annual rye/buckwheat/oats but that's a topic of another thread.  In areas where I can neither get tractor or cattle in like my apple orchard and the cursed plant is present I want to graze with rabbits in hutches ala Salatin style rabbit tractors, followed by chickens scratching up remaining plants and then overseed with rye/buckwheat/oats to stress out this evil weed.   RK is bitter and poisonous to horses.  It would account for maybe 40% of the rabbits fodder max.  Does anyone think it would harm the rabbits?  I sure would love to turn knapweed into hassenpfeffer .  

Thanks

Yup. All the knapweeds varieties are safe for them. Goats, too, so if you're struggling that bad with it, maybe you could borrow a few goats...