We used to grow wisteria as an ornamental and slightly unusual plant but when we came to Georgia, we found out that it is quite common and grows wild on the trees all over the area around Augusta. In fact, it is considered a weed in some cases. There are eight different species of wisteria and there is quite a complex taxonomy for the plant. Here is a quote from the Wikipedia article:
The botanist Thomas Nuttall said he named the genus Wisteria in memory of Dr. Caspar Wistar (1761–1818). Questioned about the spelling later, Nuttall said it was for "euphony," but his biographer speculated that it may have something to do with Nuttall's friend Charles Jones Wister, Sr., of Grumblethorpe, the grandson of the merchant John Wister. (Some Philadelphia sources state that the plant is named after Wister.) As the spelling is apparently deliberate, there is no justification for changing the genus name under the International Code of Botanical Nomenclature. However, some spell the plant's common name "wistaria", and is decisively for the "wistaria" spelling.