Beggarticks and sticktight are colloquial names given to several members of the genus Bidens whose fruits are achenes (small, dry, seeds) with barbed prickles or horns that disperse by adhering tightly the clothing or fur of passersby. Many is the time I have returned from an autumn walk and needed to remove literally hundreds of “beggerticks” from my jeans.
These beggarticks plants, photographed on the banks of the Tule River (Shasta County CA), are Bidens cernua. Because the flower heads begin to nod downward with age this species is known as nodding beggartick or nodding sticktight. B. cernua is also known as bur marigold or nodding bur marigold. I am not certain why the appellation “marigold” has been attached to this plant other than the fact that both marigolds and nodding beggarticks are members of the sunflower (aster) family – the flowers do not look alike, the leaves are different and they do not belong to the same genus.
Nodding beggarticks are native annuals and are found throughout most of the United States. Beggarticks have spread and established themselves over much of the Northern Hemisphere. Found in moist soils in low areas and waste places, along lake and river shores and in wet ditches, sloughs and canals, nodding beggarticks can form massive colonies and often are considered a noxious weed. However they are not commonly found in cultivated fields.
Variable across their range, nodding beggarticks have fibrous, shallow, branching roots and branching stems which can grow up to four feet tall. The opposite leaves are toothed or smooth, not lobed and sessile (without stalks). In autumn the leaves turn a purple color. The composite flowers consist of six or eight ray flowers with yellow rays that come to a point at the tip surrounding the orangish disc flowers. Two series of involucral bracts surround the flower head. The first set of bracts are egg shaped, yellowish green with dark streaks and a bluntly tapered tips. The outer bracts are darker green, lance shaped and spreading or downward bending. The seed of nodding beggarticks is wedge-shaped and has four horns at the tip.
Birds and ducks eat beggarticks seeds. Bees, wasps, butterflies and moths drink the flower nectar. Caterpillars of certain moths and butterflies as well as beetles, aphids and other insects feed on nodding beggarticks leaves. Supposedly nodding beggarticks leaves can be eaten as a potherb, something I have never tried.
To confuse matters, there are plants in the borage family also commonly known as beggarticks or sticktight because they too have single-seeded fruits with barbed prickles on the end that cling to passing cloth or fur. These “beggarticks” are not at all related to the members of the Bidens genus.