Eucalyptus paniculata gray ironbark

Eucalyptus paniculata fruits. John Rawlings, ca. 2005

As you walk north on Lasuen Mall from Campus Drive East toward El Camino Real passing well-spaced blue gums but just before you reach the vernal pond on the right, you will see two old gray gums on the left (location). The bark is rough and dark but the leaves are too narrow for a blue gum, though possibly indicative of an iron bark. However, the fallen fruit exhibit the terminal panicles of sevenfold clusters of buds or fruits (one or two frequently missing particularly when in fruit) characteristic of the gray gum. There are a few more gray gums beyond in the general direction of the intersection of Palm Drive and Arboretum, including a beautiful one with several trunks (location).

This uncommon organization of the fruit may be compared with that of a branchlet of E. polyanthemos, nearby, which also exhibits a paniculate inflorescence. Most of the eucalyptus on campus usually bear their flowers in axillary and terminal umbels or, in the case of the ubiquitous blue gums, bear single, rather large flowers.

Eucalyptus paniculata voucher. Courtesy of Prof. Matt Ritter and Robert F. Hoover Herbarium, Cal Poly State University

Illustrations: E. paniculata gallery.

Related material: Eucalyptus checklist.