This plant appears as a mass of impenetrable, 3-foot, swordlike leaves tapering from ½ inch to zero with wicked thorns every ¼ inch. Each leaf terminates in a stem-clasping spoon.
A specimen growing in the inner southwest island in the Inner Quad may be an original planting from 1890 and is likely the plant shown as Bonapartea of the earliest plant list of the Quad circles (undated). Another scenario is that it was first transplanted from the Arizona Graden to the old Sequoia Gardens on Serra St. and later moved into the Inner Quad.
This may be the same plant reported by Albert Wilson as D. glaucophyllum (syn. D. glauca), another Mexican Dasylirion in cultivation, in the old Sequoia Gardens. He estimated it to be about 25 years old in 1930 or so with a five-foot trunk, about its maximum height. (Albert Wilson, Distintive Trees, Shrubs, and Vines in the Gardens of the San Francisco Peninsula, 1938). D. glaucophyllum also has blue-green leaves, perhaps slighly narrower than D. wheeleri. The trunk can be erect or procumbent, the leaves .9–3 cm. wide. In ours, the leaves at their widest are about 15 mm.
Name derivation: Dasylirion – from the Greek dasys (thick) and lirion (lily), referring to the thick stems and lily-like flowers; wheeleri – named for George Montague Wheeler, 19th century surveyor and director of U.S. Army surveys of the Western U.S.; glaucophyllum – blue or greyish/bluish leaves; having bloom on the leaves (etymologies courtesy of Botanary).
Related material: See different versions of the Inner Quad Tree Map at Tree Maps and Tree Walks.
About this Entry: The main text of this entry is from the book Trees of Stanford and Environs, by Ronald Bracewell, published 2005. John Rawlings added notes on the possible history of the Inner Quad specimen.