Douglas,

I interseed a persistent, innoculated, red clover seed along with a clover based pasture mix in the early spring with a rented no-till drill when I see a pasture with grass only.  

I like red clover in the mix as a source of free pasture nitrogen fertilizer and also as a forage source that seems to come on or stay strong in warmer weather when the grasses start to peter out. 

So far it seems like once I do this I have not had to reseed.  A couple pastures I interseeded 5 years ago still have a good stand of red clover. It seems a key is to not graze it down to low and let it regrow to about 10" or higher before grazing again.

I am hoping that with the distributed manure from rotational grazing providing all P & K + and clovers providing N that I don't need to fertilize pastures. The last few years od soil tests show this is working.

I am going to apply some AMS to a couple pastures in the next week or so to see if it boosts early spring growth the way it did this year in an accidental experiment.

Jim at Dawn