Buttonbush Dodder (Cuscuta cephalanthi)

Description

This herbaceous parasitic vine is a summer annual that is several feet along. It clings to adjacent vegetation using suckers (haustoria) on its stems. Lacking chlorophyll and a significant root system, this vine is dependent on its host plants for water and nutrients. The stems are usually pale yellow, sometimes becoming pale orange with age; they are glabrous and terete. Alternate leaves along the stems are reduced to tiny scales, or they are absent altogether. Small clusters of nearly sessile flowers occur at intervals along the stems. The peduncles and pedicels of these flowers are pale yellow to pale orange and glabrous. Each flower spans about 3 mm. (1/8" across), consisting of a white corolla with 4 lobes, a light green calyx with 4 lobes, 4 stamens, and an ovary with a pair of divergent styles. Less often, a flower may have a corolla with 5 lobes, a calyx with 5 lobes, and 5 stamens. The lobes of the corolla are deltate-ovate in shape and ascending to widely spreading. The calyx is glabrous with rounded lobes; it is shorter than the corolla. Both the corolla and calyx are short-tubular and bell-shaped (campanulate). At the base of the stamens within the corolla, are fringed scales that require at least a 10x hand lens to see. There are no floral bracts underneath the flowers. The blooming period occurs from mid-summer to early fall, lasting about 1- months. There may be a mild floral fragrance. In the absence of insect pollinators, the flowers are self-fertile; they are replaced by globoid seed capsules spanning 3-5 mm. across. The glabrous seed capsules are surrounded by the withered remains of their corollas; they are initially light green, but turn brown at maturity. Each capsule is 2-celled, and each cell contains 2 seeds. The capsules eventually split open to release their seeds. The seeds are about 1.5 mm. long (or slightly more), ovoid in shape, and slightly compressed. There is a rudimentary root system at the seedling stage, but this is abandoned shortly after a suitable host plant has been found. If no host plant is found, the seedling dies within a few days.