This past week has been an unbroken streak of sunshine and intense blue skies in Boston, with crisp cold temperatures—perfect for extended walks in the Arnold Arboretum. As I wandered in the Maple Collection, one tree took my breath away, an Amur maple, Acer tataricum ssp. ginnala (701-63*E), whose translucent membranous winged fruits (samaras) collectively made the entire tree glow. Almost all of the fruits of this Amur maple still hang by a thread that seems poised to break on the next windy day (lower left image). The beautiful dichotomizing and anastomosing venation of the wings, a reminder of the complexity of small things in nature, is evident in magnificent detail.
I found myself repeatedly drawn to winged fruits this week—those wonderful evolutionary innovations that allow seeds to disperse far from the mother plant with just a current of air. Characteristic of maples, ashes, elms, birches, tulip poplars, and many more, their muted colors are a rainbow of browns, tans, and beiges. As wind-borne fruits (hence the aerodynamic wings), eye-catching color is not important—no need to attract an animal to do the work of moving away from the parent tree.