Wistaria are coming into bloom. For that matter, the world's largest one in Sierra Madre has been blooming for a fortnight. Altogether, they are a lovely addition of lavender, purple, pale blue, even pink, to the other colors of spring.
To the botanist wistaria are wisteria , according to Jim Bauml, the senior biologist and plant taxonomist at the Los Angeles State and County Arboretum in Arcadia. The genus was named in 1818 for Dr. Casper Wistar, an anatomist at the University of Pennsylvania, in celebration of his contributions to science. Whoever first wrote it down spelled it wrong, thus wisteria instead of wistaria , tarnishing ever so lightly the tribute to the good doctor. The error is perpetuated in technical books and dictionaries, but common usage accepts a spelling that honors Dr. Wistar.
How an American professor got into the act is not altogether clear, because the two native American species have never amounted to anything. Gardeners prefer the Chinese wistaria, exported for the first time from Canton to England in 1816, and the Japanese wistaria, brought to Europe by a German doctor in 1830. One way to tell them apart, incidentally, is that the Chinese vines twine counterclockwise, the Japanese clockwise. For what it is worth, the American natives both twine counterclockwise.