Fabaceae (pea family) Acacia

Acacia dealbata silver wattle

Tasmania, Victoria, New South Wales, Queensland
Acacia dealbata (trunk on left), Lomita Drive. Sairus Patel, 16 Feb 2018
Leaf of Acacia dealbata, west side of Lake Lagunita. John Rawlings

The brilliant yellow displays in February and March, which distinctly precede the coming of spring and add color to winter’s end, are mainly from this species.

The silvery-gray feathery leaves are bipinnately compound: they are divided into a dozen or so pinnae each with three dozen or so pinnules about ⅙ inch long. See raised glands on the upper surface of the leaf’s main axis at the junction of each pair of pinnae.

The leaf stalks run on as fine, angular ridges on the branch. The much rarer green wattle (A. decurrens), unknown around here, has dramatically angular or winged ridges; its leaves are not silvery but rather an ordinary green.

A large silver wattle is just north of Museum Drive, between Palm Drive and Lasuen Street, within the relocated pool from the old men’s gym; note the foundation stones of the columns nearby. One on Campus Drive at the southeast corner with Lomita Drive, near the Anderson Collection, fell down in 2023 and may be resprouting. Substantial numbers can be found in the area of Frenchman’s and Gerona Roads.

Silver wattle is an invasive weed in Bear and San Francisquito creeks in Jasper Ridge Biological Preserve and along other campus waterways.

Acacia dealbata compound leaf and fruit. John Rawlings

Illustrations: Jasper Ridge plant photo archive.

Name derivation: Acacia – Greek akis, a sharp point; dealbata – whitened (young shoots and leaves).

About this Entry: The main text of this entry is from the book Trees of Stanford and Environs, by Ronald Bracewell, published 2005. The sentence “I have concluded that I cannot tell one from the other and look forward to being instructed” was replaced by some notes on the glands and twigs by John Rawlings (ca. 2010). Edits and note on Governor’s Ave specimen removal Feb 2018 (SP). Old men’s gym location added Mar 2019 (SP). Edited main entry to be for A. dealbata only, with just a quick reference to A. decurrens which doesn’t occur on campus; removed location at Governor’s Avenue where it makes a corner at Lake Lagunita; edits (Jan 2023, SP).