NO! IMO 3 is too old. I got a cattle protein tub with a bunch of yearlings (chestnut and chinquapins) that I'm going to get out soon. Much easier to plant them at that stage. Should have higher success rate, too.
Do you leave the trees growing in protein tubs out all winter? Also do you drill drainage holes in the tubs. Also what kind of soil you are using. Interested in your setup because I have access to a bunch of protein tubs.
Buried the tub flush in the garden, filled with garden soil. Put the nuts in, topped off with more dirt, weighed down chicken wire over it. I did drill a drain hole in the bottom of the tub. I went this way as I've had a few potted trees freeze dry over the winter if not put in the dirt. I plan to soak it heavily, loaded it in the bucket of the tractor and head out to plant. Muddy roots shouldn't dry too quickly as I plant.