This magnificent Japanese beech (Fagus crenata) is from this year's Kokufu Exhibition. I cropped the original (just below) for a closer look.

We can't stay away from the Kokufu Bonsai Exhibition for long. Just in case you are new to this, Kokufu is an annual bonsai exhibition that's held in Tokyo in the late winter of each year. This year's was the 93rd. There was a break during WW2, but otherwise they occur like clockwork.
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All the original (full size) photos shown here are borrowed from Kazematsu Bonsai.

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One of the advantages to winter bonsai exhibitions is you get to see and appreciate deciduous trees in all their bare-skinned glory, including the all important line and taper that flow all the way from the base of the trunk out to the tips of each tiny twig. Getting this just right is the result of years of skillful trimming.

 Stewartia (S monoadelpha) are renowned for their clean lines. strong nebari and especially their lovely reddish exfoliating bark.

If you see a root-over-rock bonsai in Japan, chances are it's a Trident maple (Acer buergerianum). This one is no exception.