I wish I'd read your comment about crabgrass awhile ago. I have a little section of plot that has failed each of the past two years due to a lack of thatch. Likely more due to bad timing on my part, rather than super poor soil. And I just did it again, broadcasting sunflowers in an attempt to get something growing before the crabgrass germinates. Unfortunately the birds have eaten it all before it had a chance to come up due to lack of thatch.
I just realized within the last couple of days that I need to let the crabgrass come up and get tall enough so I can then do a proper spray, broadcast, and mow. I'm thinking turnips, radishes, and red clover around the first of August. All have grown well for me before on my soil, and won't need a ton of thatch covering it.
Thanks again for all the info you've shared!