An Illustrated Guide to ARIZONA WEEDS
The University of Arizona Press
WESTERN CLAMMYWEED, clammyweed
WESTERN CLAMMYWEED-Polanisia trachysperma Torr. & Gray
DESCRIPTION-An erect branching glandular hairy annual, very sticky and clammy to the touch, with an unpleasant odor, 1/3 to 3 feet high, reproducing by seeds. The leaves are divided into 3 lanceshaped leaflets; the upper and those of the flowering stems are not divided.
The 4 petals are whitish or yellowish, but the numerous ( 12-32) stamens, with their long purple stalks, give the flowers a purplish appearance. The flowers are densely crowded along the upper part of the stems. The sticky seedpods resemble mustard pods. They are long and slender, and at maturity are 1 1/2 to 2 1/2 inches long, on jointed or unjointed stalks 7/8 to 1 inch long. The reddish brown seeds are rounded, about 1/12 inch in diameter, grooved through the center, and the surface is minutely pitted in circular lines.
DISTRIBUTION-Western clammyweed is a native plant growing in disturbed soil along roadsides, waste places, denuded areas, and in sandy canyon washes or stream beds from Navajo and Coconino counties southward; 1,000 to 6,500 feet elevation; flowering May to October.
Copyright (c) 1972 The Arizona Board of Regents