Bidens leptocephala, commonly known as Arizona Beggarticks or Fewflower Beggarticks, is a wildflower found across parts of the southwestern United States and northern Mexico. This annual herbaceous plant belongs to the Asteraceae family, often recognized for its daisy-like flowers. While its common name might suggest a widespread presence throughout Arizona, it thrives in specific environmental niches within its native range.
Understanding Arizona Beggarticks
Arizona Beggarticks is an annual herb that typically grows to a height of 10 to 50 centimeters (approximately 4 to 20 inches). It has erect, slender, green stems. The leaves are light green, arranged oppositely along the stem, and are 1 to 2 pinnately divided, meaning they have a feather-like appearance with multiple leaflets branching off a central stalk. Each leaf blade is rounded-deltate in shape, with lobes that can be ovate, lanceolate, or linear.
The plant’s small flower heads are yellow, yellowish, or whitish in color. These heads are borne singly or in small clusters of two or three, each atop a long, slender stalk. It rarely displays prominent ray florets, having only two to three, or sometimes none. The central disk florets, which are the small, tubular flowers in the center of the head, number between five and thirteen.
The common name “beggarticks” originates from the plant’s seed structure. The genus name Bidens is derived from the Latin words “bis” (twice) and “dens” (tooth), referring to the two barbed awns on the plant’s achene fruits. These barbed bristles enable the seeds to attach to animal fur or human clothing, facilitating their dispersal. This effective dispersal mechanism gives the plant its common name.
Habitat and Distribution
Bidens leptocephala is native to the southwestern United States, found in Arizona, New Mexico, and Texas. Its range extends southward into northern Mexico, including Baja California, Chihuahua, and Sonora. Within Arizona, this species is found in the central, southern, and northeastern parts of the state, though it is predominantly a southern Arizona species.
This plant thrives in specific environmental conditions, preferring mid to higher elevations, between 900 to 1,800 meters (3,000 to 6,000 feet) above sea level. It is commonly found along streams and in other moist areas, indicating a strong association with water sources. The plant prefers shady, sandy soils within these riparian zones.
While some Bidens species are adaptable to disturbed areas, Bidens leptocephala is found in more specific habitats, associated with the edges of water bodies or moist, shaded sandy patches. Its narrow preferred habitat suggests it requires consistent moisture to flourish within the arid and semi-arid climates of its native range. The plant’s presence indicates a healthy, moist microclimate in an otherwise dry landscape.
Ecological Significance
As a native plant, Bidens leptocephala contributes to local biodiversity in its natural habitats. Its presence supports the ecological balance of riparian areas and moist sandy environments in the southwestern United States and northern Mexico. The plant’s flowering season, from August to October or September, provides a resource during these months.
The yellow or whitish flowers of Arizona Beggarticks attract various pollinators, including native bees and butterflies. These insects gather nectar and pollen from the blooms, aiding in the plant’s reproduction.
While direct consumption of Bidens leptocephala seeds by wildlife is not always documented, Bidens species seeds are known to be a food source for some birds and small mammals. The plant is listed as “Secure” (G5) worldwide by NatureServe, indicating a stable population status within its native range. Unlike some other Bidens species, Bidens leptocephala is not noted for being invasive in its native distribution.