Our best con-tillers down here - keep in mind our sandy soils and milder winters - LOVE rye. It gives a lot of biomass and makes a great cover crop, outgrows wheat and oats. We usually plant corn the 2nd and 3rd week of March, and sometimes plant corn into green rye and kill it at the same time.

The mulch lasts so much longer than any other kind of cover we use, our nematodes don't thrive in it, and the root system it leaves reduces compaction better than anything else we have ever tried. I'd guess that rye saves us about one irrigation a year, too, as the moisture just holds so much better, the root system of the crop is so much more vigorus.

Here is a link to our Conservation Tillage Alliance website and some pictures, http://www.uscta.info .  LINK WILL NOW WORK, HAD A PERIOD IN THE URL- Carl, 10/13/06.

I can't speak for how well it will work at higher latitudes and on heavier soils, but speculate that many of the same principles will apply. As for tying up N, yes we see some of that, but we get so much LESS runoff of fertilizer and water that the negatives there are reduced. We often get grazing from Thanksgiving to Christmas from the rye, then again in February. We take the cows off in late February, see the rye grow back a little, then plant corn.