Forages

Weeds-(Dandelions, Asters) I also have thistles, lambs quarters and other weeds. Weeds are often quite nutritious, but don't really regrow very much. Of course poisonous weeds should be avoided or removed before grazing. (I have Milkweed in one pasture and just pull it up before grazing. )
Various grasses- I'm not sure what varieties I have. I do have Quack grass and about 5 other kinds of grass. Grasses generally do well in cool weather.
Red Clover- I have a newly seeded 5 acre pasture of about 90% red clover. I have not grazed it yet this year and it is very tall- about 4 ft. (I'm also planning to frost seed some other pasture with red clover next spring.) Red clover is very nutritious, but can cause bloat if the animals are not used to it and/or it is wet. The other downside is red clover is hard to dry for hay. Red clover does well in hot dry weather. A local sheep farm flushes their ewes on about 20-30% red clover and they do not have fertility problems. (They have about 210% lambing.) Clovers have a lot of estrogen and are supposed to cause fertility problems in sheep. I do not know if I'll take the chance and feed my ewes red clover at breeding time or not.
June grass- I don't like June grass as the sheep don't eat it very much and it does not get very tall.
Birdsfoot Trefoil- sheep love it! Trefoil is like a non-bloating alfalfa. It does well in heat and has a high tannin level so helps reduce parasites. An added bonus is honey bees love it. Last year they preferred it over alfalfa (from neighboring fields) and clovers. The only down side is it can be hard to establish. When I planted it I intentionally overgrazed to kill/stunt the grasses in the pasture before planting it by no till drill. Then I let it sit all summer and fall without cutting it or grazing it. I did graze it after it froze hard (about Oct./Nov.) You do need to let it rest from Sep. until the first killing frost. This does take planning to have these pastures rest until then!

Alfalfa- I only have a small amount of alfalfa in one pasture. I have not had any trouble with bloat, but alfalfa gets steamy when mature and also can get killed easily by over grazing or just not having enough time to rest in between grazings. Of the two alfalfa is better for hay while Trefoil is better for grazing.