Silver birch? (1st post many pics)

[Snake23]

First off, I'm new to bonsai in the sense that this year is my first year practicing bonsai for myself from collection to end... I've done trimming and wiring of existing bonsai for other people but nothing really extensive. My landlord wanted these little whips cut done and i decided to dig them up either though it'll be years before this one can really be called a bonsai. I'm thinking it is a silver birch... it has the silver/gray backed leaves but haven't really found an exact id with pictures and what not.
I was wondering how i should really go about this one....




My main problem is i like everything about it but it's not really bonsai but more of a pretty curved sapling. My gut says don't touch it but my brain says do stuff....

Right now the pot it's in is about 5 inches deep because it's what i had and because i wanted to make sure the root it grew off of produced its own roots before i transfer it to the 5 gal. It was dug up during a warm spell in February. It is bent because it grew up under our grill last year and is roughly 2-3 years old.
Came from this tree:

 

[Paradox]

Your gut is correct. This guy needs to grow and get a trunk before it can be trained for bonsai which will take several years. You just got it out of the ground and into that pot. It would be better to let it recover. If you do anything to it now, it might kill it. I dont think it will grow well in the pot you have it in now. We usually dont put trees into "bonsai" pots until they are finished training. You need to keep it outside. It wont survive inside.

I have never seen a birch with bark like the picture you show of the big tree. The leaves also dont look right for a birch. It is an interesting looking tree. Are you sure its a birch?

 

[brewmeister83]

Not quite sure what you got there... The bark of the parent tree looks like something from the Populus genus (poplar/aspen group) but the leaf color sounds like it could be silver maple (Acer saccharinum). To be really sure we need to see a close up of the leaf and twig structure as well as where you live (location is key to identifying some species - like if you're on the west coast, my east coast knowledge of trees won't be of that much use). But whatever it is I'm not guessing silver birch unless you live in Europe - those trees don't grow natively in the US

 

[frozenlarch]

I'm going to take a slightly educated guess, and say Quaking Aspen.
Based on the trunk in the photo, and the description of the leaves, I would almost be willing to bet money on it... Almost.


Edit: After a bit more research, I would suggest googling "white poplar"...

 

[Snake23]

I live in the Midwest (Wisconsin) and the tree was put in a 3 gallon tub last weekend; the other pot was just temporary. It is kept outside but I took it inside to get better pictures with a plainer background. I will post some close-ups of the leaves when the leaves are a little bigger. The landlord and one of the older guys down the street (my street has about 20 of these trees on it) said they thought it was a birch, but like I said, I wasn't so sure.
I also thought aspen but the leaves are silver.... closer to white on the back and the juv truck has almost a silver dusting I can't get a good picture of. I have found both pictures labeled as aspens and birches that could be the an exact copy of the tree both without the silver/white leaves.
Do silver maples has the white paper-like bark too?

 

[brewmeister83]

Do silver maples has the white paper-like bark too?

I retract the silver maple comment, I was looking at the leaf pics on my phone, but I just got a better look on the computer. I'll stick with what I said before - aspen/poplar group, probably quaking aspen like frozenlarch said, but I've never seen a quaking with multiple trunks before - just lots of lodgepoles in a grove.