By the leaves, I surmise this is Quercus Robur (common oak) Judging from past DUG oak, (which I gave away and subsequently turned into a 20 foot field tree) I am assuming they need some room. I think I will have to cut the tap root. It is in a narrow tall pot now. Started this last summer from a 2 inch "starter" and now grown a bit. (spoon in pic for scale) I'm wondering if I should pot it this spring in a wider but fairly DEEP pot or go wider but not too deep? The trunk has thickened considerably from when it started. It wanted LOTS of water this year. I don't think I want it in a narrow pot because I want to encourage the wider roots to thicken the trunk more. Is a ...shallow...pot a bad thing? Even if it's pretty wide? I plan to shorten some of these longer branches to the several lower multiple bud levels. Or should I go fairly large to accommodate a spreading root system? ???