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Smoketree / Smokethorn

Psorothamnus spinosus

Smokethorn, Psorothamnus spinosus, Watercolor © by Michael Plagens

Watercolor from live specimen found at Bouse, Arizona, 06 April 1993.

detail of the trunk and bark, Smokethorn, Psorothamnus spinosus, photo © by Michael Plagens RANGE: Low, frost-free areas from Yuma, Arizona, north to Parker and in scattered locations further east as in far western Pima and Maricopa Counties. Also southeastern California and northwestern Mexico.

TREE: Reaching 5 to 10 meters. Main branches and trunks are gray streaked with black. Young branches and twigs are gray-green and carry on much of the photosynthesis.

ARMED: Many, long, very sharp, sweeping spines.

LEAFLESS: Nearly leafless. But, usually an occasional simple leaf on the new growth can be found. Smokethorn bears a superficial resemblance to the crucifiction thorns.

FLOWERS: Showy, vivid-purple, pea-flowers appear late spring/early summer. There is a small bright orange gland on each of the sepals.

FRUIT: Like other members of the bean family, the fruit is a pod, but smokethorn has a small pod containing usu. only one seed.

Fabaceae -- Bean Family

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Copyright Michael J. Plagens, page created 13 May 2001,
updated 21 February 2013