An Illustrated Guide to ARIZONA WEEDS
The University of Arizona Press
MORNING GLORY FAMILY-Convolvulaceae
FIELD BINDWEED-Convolvulus arvensis L.
DESCRIPTION-A prohibited noxious weed in Arizona, field bindweed is a prostrate perennial from a thick, branching, deeply penetrating taproot, which reproduces by seeds and by extensive horizontal roots and rhizomes. The slender stems, twining or trailing on the ground, are 1 to 3 (or 10) feet long. The leaves are alternate on stalks 1/4 to 3/4 inch long. The leaf blades are eggshaped with the base squarish, heartshaped, arrowshaped, or the 2 lobes pointed outward. They are 1/2 to 1 7/8 inches long, 2/3 to 1 inch broad, and usually roundish at the tip.
The funnelshaped flowers are white or pink, 2/3 to 1 inch long, and 3/4 to 1 inch across. They occur singly (sometimes 2 or 3) on stalks 1 to 2 inches long in the leaf axils. A pair of narrow pointed bracts l/8 to 1/4 inch long occur on the flower stalks 1/2 to 1 inch below the flower.
The globeshaped, point-tipped seedpods contain 4 chocolate brown seeds. These are somewhat eggshaped, the surface roughened, 3-angled, or flat on 1 side, rounded on the other, and l/8 to 1/5 inch long.
DISTRIBUTION-Introduced from Europe, field bindweed grows mostly in dry soil along roadsides, in open fields or edges of cultivated fields, pastures, on fences, yards, and waste places of farms. Also found in alfalfa, small grains, cotton, and sorghum. Common throughout the state; 100 to 8,500 feet elevation; flowering March to November. Considered the most noxious of all weeds in several western and midwestern states, this drought resistant plant with its unusual root system is almost impossible to eradicate from an infested area.
HEDGE BINDWEED-Convolvulus sepium L.
DESCRIPTION-Similar to field bindweed, but the 2 bracts are larger, 1/2 to 1 inch long and are immediately below the flower. The flowers are larger, 1 1/2 to 2 1/2 inches long, and the leaves also are larger, 2 1/2 to 3 1/2 inches long.
DISTRIBUTION-Not common in Arizona except locally in somewhat moist soil, from Apache to Coconino counties; 6,000 to 7,000 feet elevation; flowering June to August.
Copyright (c) 1972 The Arizona Board of Regents