Starting my maple bonsai from seed (first growth season)

[nimaisamoose]

Hello all!!
So I've got a load of trident maples I planted from seed earlier this year (UK).

This is their first season of growth and the plan is to try and turn them into bonsai down the line.

Have a rough idea of the things I should be doing in preparation for this in next few years, but my first though is this big one that's managed to absolutely explode. Do I limit its height? Any tips or specifics going into the second year of its growth after winter.

This is very much my first foray so any help would be great. All my other seedlings are much smaller though from the same batch of seeds.

 

[Arlithrien]

Looks like an amur maple to me.

 

[SeanS]

As stated it doesn’t look like a trident. Either way you should put some wire on it and put some movement into the trunk, then let it GROW

 

[Shibui]

My strategy is to work on the roots at every opportunity. Nebari is a big part of good maple bonsai and it is easier to set on the right track at the start rather than trying to correct problems later.
I allow free growth each summer but chop the trunks hard each winter when root pruning. They shoot away quickly the following spring so very little growth is actually lost by winter pruning and regular pruning will give much better taper and some bends in the trunk as a bonus.
I no longer wire fast growing trunks. Embedded wire is a real risk when trunks are thickening quick. Wire and bend can give bends in a trunk but will not give all important taper. Wired bends can also look really artificial while bends resulting from trunk chops seem to be more natural. Just my 2C