I don't know if this has ever been mentioned before, if it has I'll apologize for boring you. I recently encountered a situation very similar to yours. My uncle wanted to put in a couple of food plots, and his choices were very limited. The one area was heavy clay with decades of compaction.
I suggested after we prepped the site we use polymers, he didn't have a clue what I was talking about and looked at me real funny. To make a long story short I ended up buying them for the plot. I opted for the ones that were pre fertilized and last appx ten years!
I love these wonders of science, and his Imperial clover patch was beautiful! I might add also that during the heat and drought of Michigans August it continued to grow thick and green requiring a good mowing.
If your interested in looking for yourself I believe you can find this at www.terawet.com
Just the polymers themselves are good subject for conversation. Good luck with your plot. I found the leftover package in the garage this afternoon. We used the T-200, these are slightly smaller microns than the other choices, and there life expectancy is advertised at 7 to 10 years. I purchased two seperate packages totaling two pounds at a cost of appx. 15 dollars apiece.
Like gramps used to say, "Why is it there's never time to do it right, but there's always time to do it over?"