interseeding works great and i highly recommend that everyone is continuing to seed. but u just named 2 ugly 'weeds' and u got alot of work ahead of u. read up on mangement techniques, this link is one of many good books on the subject.

http://www.naturallycurious.com/cgi-local/SoftCart.exe/online-store/scstore/p-1559633204.html?E+scstore

u mentioned late spring burn. why not a fall burn? why not a fall burn the seed? no strat, no muss, no fuss. i find that a fall burn is easier to control, more productive in management of many woodies and easier to find the time then the spring burns. after this fall burn, one has usually a good month or so of black earth and light snow to seed into before we get snowcover and (in his best football voice) 'the frozen tundra of Lambeau'. now i know as well as u do that the last few years we havnt had that snow cover until late if ever...but im the eternal optimist. spring seeding are too close to summer for my liking.

brome burns hot and low, it could easily damage a newly seeded area. i would try to stay away from that scenario.

lastly ill say that certainly some seeds are better suited for fall, some for spring, some for summer, some respond much better when CS or 90CS or any of the other multitude of scenarios that they want. i have a rule of thumb that ill share.
if they say CS, i throw them out in the fall. if they say nothing or innoculate, i throw them out in the spring. then there are all the exceptions. that is why i usually seed an area in at least 3 times over with 3 diff mix's.

I am also leary ot seeding on top of snow, especially since my area all has slope and erosion potential. The reason I was considering it is that Prairie Moon Nursery claims that frost seeding between layers of snow is very effective.

I like your rule of thumb about timing of seeding, which brings up another question. Last year I seeded some purple and white prairie clover, and round headed bush clover during november (going against your rule of spring seeding things that require innoculation). I had very poor results. The seed I used was boughten de-chaffed seed. Somebody later told me that using using de-chaffed purple prairie clover seed usually yeilds poor results when fall seeded, but good results when spring seeded. They said that using unprocessed (chaff not removed) seed will work much better for fall seeding. Anybody have any experience with this? Also will the innoculum over-winter when on the soil surface?

I posted my original post on the Native Plants forum also and a user replyed that fire may actually stimulate some prairie species to germinate. If anybody is interested in this topic I would suggest you check out his reply to my post on the native plants forum. I did some searching and found some research that shows that indeed some species exhitit increased germination rates when exposed to fire. The mechanism for some species is the heat, for others it is chemicals contained in the smoke. Very interesting stuff. Here is a link:

http://www.nps.gov/plants/chicago04/posterabstracts.htm#smoke

I am still wary of burning up all that expensive seed!!!