Convolvulus arvensis and Calystegia spp.; bindweed [Convolvulaceae]  Trailing or twining perennial herbs with showy, white to pink, 5-parted, funnel-shaped flowers.  Calystegia sepium and C. spithamea are native plants, with the latter occurring in drier habitats.  Convolvulus arvensis is an invasive Eurasian native and classified as a noxious weed throughout most of the country.  All may be found in fields, roadsides, thickets, and waste places, flowering throughout the growing season.  [127]