The work doesn't end when the seeds are in buckets. The seed needs to get to a nursery bed to start growing. Don't leave them in your trunk like a box of clothes you swear you're going to donate any day now... You've got a couple options for selling your seed; do what works best for you. Reach out to the prospective buyer before you collect. They will tell you what species they are interested in, what processing you need to do, and what information you should include regarding the collection.
The state nursery is the largest producer of seedlings in the state. They supply seedlings for state reforestation projects, and stock most SWCD tree sales. Historically they have focused more on conifer species, but are bolstering their hardwood sales (with our help!). They accept seed from around the state.
The DNR's seed bank is at a historical low, but it's still important to call ahead to make sure they need what you plan on collecting. The DNR may require specific seed processing (i.e. float tests). Check the website and confirm with the forester. Once you get the green light and collect the seed, you'll bring it all to your regional buying station where they will confirm the quality and quantity of the seed.
The DNR will no longer write checks at their offices. Instead, as a registered supplier, you can choose to receive payment through direct deposit or a check in the mail. Instructions for registering.
The FFGC is a network of small farmers who also grow trees. Their focus is on climate- adapted seedlings, and collaborate with researchers at the University of Minnesota-Duluth to study assisted migration (moving genetic material north to jumpstart adaptation to future conditions). They primarily grow hardwood species, and source seed from the southern half of the state. For more details and to sign up to collect, fill out this form or reach out to seeds@farmforestgrowers.com with questions.
Depending on where you live or collect, there are other nurseries who may be interested in your seed. Check out other state nurseries (like Wisconsin DNR); local and tribal nurseries; county land departments (who may have sites set up for collection); and companies like PRT.