I found a lot of groundnuts growing in the woods, but they are in a heavily bushy area and high climbing up into small trees. I cannot follow the vine to the ground, so I cut some large lengths of vines off the top. Can I propagate these and have them grow tubers for me to harvest?
Yes, you can propagate from root cuttings.
Cut pieces 4 to 8 inches long and plant them 3 to 5 inches deep in pots.
Keep moist while rooting and they should root in 2 to 4 weeks.
Here is a link with more information.
https://www.gardeningknowhow.com/ornamental/vines/groundnut-vine/how-to-grow-groundnuts.htm
Where can I get some groundnuts to grow?
We don't sell plants, or deal with anyone who does. There are many places online that will sell them, though.
Never have seen anything like this in the 10 years I have had this garden.
Since it just popped up in your yard I figured it was native so checked native vines in Rhode Island. I believe you have a common groundnut, Apios americana.