A yose (group-style) bonsai specimen of Acer palmatum, Japanese Maple, developed by Stanley Chinn currently on display at the Brooklyn Botanic Garden. Yose typically group multiple specimens of the same, or closely related species, in the same planting to simplify cultural requirements. Chinn’s masterful touch is the selection of cultivars with different fall foliage colors. This specimen is unusual in that there appear to be only two, rather than the typical three or some other odd number, of the trees in the grouping. 
There is no better time of year to visit the Brooklyn Botanic Garden’s C. V. Starr Bonsai Museum than right now. Most of the trees on display are in peak fall foliage color. And while the wind has knocked the leaves off many of the trees on the grounds, the sheltered bonsai have been spared those indignities.
This season, they’ve placed an additional display table at the northern end of the greenhouse, opposite the entrance.
Beautiful photos. Love the Bonsai Museum.