Kind of far along with to mess with now. But if you want a single stem leave the tallest trunk and cut the others off. Birches don't react well to having branches of any size cut off, so if you want to make alterations do it before the tree gets any bigger.

Since it is a tree planted for bark one with a clump habit like this makes more of a show than one that has only one stem, might actually therefore be considered preferable. Both single-stem and clump form specimens are grown and sold.

Another consideration might be the shading the branches provide. Birch have fairly shallow roots and like them cool. Since you are in SC, I'm guessing this is River Birch growing pretty far south. Keeping shade on the roots can only help.

tree trunks thicken.. they do NOT elongate up ...

you prune it.. to make it what you want it to be ...

birch.. with its attendant borer issues .. is the one tree.. i would look for proper pruning season ... in SC ...

and then i would buy a tree saw.. like the one at the link...

and raise the canopy to the height you want...

then i would decide if you want less trunks ...

and then i would kill grass in a 5 foot circle.. and mulch it properly .... to keep the idiot with the weedwhip away from it ...

ken

Here is a link that might be useful: its $5 less than when i linked to it last week????

Prune, prune, prune ...this tree looks as though it is growing very well.. no need to worry in regards to the type of pruning this tree needs- some thinning to establish scaffold branching, and yes raise the canopy to 3 to 4' for now, if want to see the exfoliating bark. Pruning this time of year will provide some callousing before leaf drop; and, pruning at this age will produce minimal wounds which should be completely calloused in 2-3 years

Prune in summer and not in early spring. Spring pruning before leaves come out makes the tree bleed - doesn't hurt the tree but makes a drippy mess. I prune mine whenever it is in leaf and needs it.

hortster

Thanks for all the input !