An Illustrated Guide to ARIZONA WEEDS
The University of Arizona Press
SPURRED ANODA-Anoda cristata (L.) Schlecht.
DESCRIPTION-An erect branched annual 1/4 to 3 1/2 feet high, reproducing by seeds. The leaves are alternate, with stalks 1 1/2 to 3 inches long. The blades are triangular in outline, and may be somewhat arrowheadshaped, shallowly lobed with toothed margins, or the basal ones sometimes divided into several fingerlike lobes.
The large flower is solitary on a slender stalk arising at the base of the leaf stalk, and has 5 purple or bluish violet petals 3/4 to 1 inch long. The 5 green outer flower parts (the calyx) persist, their long lobes widely spreading under and greatly beyond the flattened disk of the fruit. On the disk are 9 to 20 fruit parts (carpers) which separate at maturity, each forming a seed-like pod. Each carper has a dark hardened spur along the back, sharp pointed and spinelike at the base, extending beyond the tip into a stiff bristle, 1/12 inch or more long, and thinly covered with conspicuous yellowish hairs. The dark gray seeds are wedgeshaped, about l/8 inch long, and prickle tipped at the narrow end.
DISTRIBUTION-Spurred anode is a native weed growing in moist soil, in cotton fields and other irrigated crops, gardens, ditches, and roadsides, also along streams and meadows, mostly in eastern central and southern Arizona, from Apache to Yavapai county and southward; 2,400 to 6,500 feet elevation; flowering August to October or November.
Copyright (c) 1972 The Arizona Board of Regents