Ironwood
Olneya tesota
Watercolor from live specimen found at New River, Maricopa Co., Arizona, 30 May 1993.
TREE: An important and sometimes large tree (12 m). The bark of young
branches is light to dark gray; older bark is dark gray and deeply fissured.
Upper lateral branches often arch downwards nearly reaching the ground level.
RANGE: Wash banks throughout the Sonoran Desert below 500 m elevation.
This tree is a good indicator of frost severity and was used as a guide to an
area's suitability for citrus cultivation.
ARMED: Sharp and slightly curved spines occur in pairs at each
node.
LEAVES: Leaves are once pinately compound and evergreen. Well
into the severe droughts Ironwood presents an unseemly verdance.
FLOWERS: In May a profusion of lilac-purple flowers makes this
one of the most beautiful desert plants. Typical pea-type flower.
FRUIT: Bean pods are covered with a short, slightly sticky
pubescence and turn burgundy-brown as they ripen. Edible seeds have a flavor
resembling peanuts.