bb940p  here's a link to some info on HRS nutrient needs. There's a specific ratio of N,P,K, that needs to be followed to get the highest protein. I don't recall offhand, too much to other stuff to think about I guess?  I usually just look up the formula on WSU's web site.

http://www.css.wsu.edu/Proceedings/2006/Young_Koenig_N.pdf

If this isn't exactly what you're looking for, go to google-hit advanced search- type in the key words,,"spring wheat", "Protein", "WSU" and whatever else might be important to you- then where it say's "DOMAIN"  type in "edu".  That will restrict any searches to universities.  You will get more info than you can read in any 2 sittings.

The formula does work,, I always get between 14.5-15.75+ % on HRSW.  Thou for me I take such a beating on the yeild I can't justify the input costs. Usually I only get about 60-65bu/ac which sucks. (if I cross my fingers pat my head and rub my stomach at the same time...)

Far as using HRSW as a "cover crop" over alfalfa,, no good answer on that one. It's very possible the alfalfa will be "lazy" and hog up the free-easy Nitrogen actually intended for the HRSW, the wheat will suffer some,, and the alfalfa won't be as hardy from having to work harder to provide it's own Nitrogen?   I have not clue one,that thought just crossed my mind.

Don't know if you're dryland or not??  But, if irrigated there is also some research about stressing (shorting water) HRSW at a specific time and inducing higher protein levels too. Just have to wander and paw through the mountains of paperwork research on the subject.

just my 2 cents