An Illustrated Guide to ARIZONA WEEDS
The University of Arizona Press
MORNING GLORY FAMILY-Convolvulaceae
TALL MORNINGGLORY-Ipomoea purpurea (L.) Roth.
DESCRIPTION-A prohibited noxious weed in Arizona, tall morningglory is an annual climbing and twining vine. from a fibrous root system, which reproduces only by seeds. The twining or trailing stems are hairy, 5 to 13 feet long. Similar to woolly morningglory, but the leaves are all heartshaped and unlobed. more or less hairy, and pointed at the tip, the blades 2 1/2 to 4 inches long, on stalks 2 to 4 inches long.
The flowers arc similar to but often larger than those of woolly morningglory. They are white to blue, or purple to bright pink, with considerable variation and different markings, 1 1/2 to 2 5/8 inches long, and 1 1/2 to 2 inches across. The 5-lobed calyx, as in woolly morningglory, is conspicuously hairy, 1/2 to 3/4 (or rarely 1 inch) long.
The globeshaped seedpods are like those of scarlet morningglory, and contain 4 to 6 seeds. The seeds are similar, but flattened and larger, about 1/5 inch long, minutely hairy except around the scar, 3- to 4-angled, and brownish black.
DISTRIBUTION-Tall morningglory is native in tropical America. It occurs with woolly and scarlet morningglories on the farms, fields, roadsides and ditches in central and southern Arizona: flowering from about June to October.
Copyright (c) 1972 The Arizona Board of Regents