Brad,
In Illinois, we have a law that assesses triple stump damages regarding illegally cut trees. Based on several direct and indirect field measurements, including geometric stump diameter and distance to the top (if it hasn’t been moved by the skidder operator), a forester can generally, and accurately, determine the approximate volume of the cut tree. Now all you have to do is determine a value.
In Illinois, the prevailing delivered veneer black walnut price range is $3.00-10.00/bd ft, with sawlog prices fetching $1.00-1.80/bd ft. When I used to investigate timber theft cases, I would take a low, high, and average estimate based on the prevailing market conditions for the area.
Therefore, if the average value were appraised at $1000, then the triple stump damage assessment would award the landowner $3000. One problem, your property is in Michigan and I am not familiar with Michigan Conservation Law. With that said, you should probably contact a local Michigan State University Extension Forester, http://www.for.msu.edu/extension/staff.htm
If you are having trouble getting what you think is a fair assessment, then I urge you to contact your local DNR forester or your local Extension Forester.
Good luck!