Virginia Tech Weed Identification Guide

Coreopsis Beggarticks: Bidens polylepis

Weed Description:  Summer annual with dissected leaves and showy yellow flowers reaching 5 1/2 feet in height.  Primarily a weed of pastures, roadsides, and noncrop areas that can be found throughout Virginia, North Carolina, South Carolina and Georgia. 
Leaves:  Opposite, with short hairs that are closely pressed (appressed) against the margins and veins.  Leaves are finely dissected and have 2 to 3 rows of lateral leaflets that are lanceolate to relatively linear in outline.  Each leaflet is approximately 1 1/4 to 4 inches long and 1/4 to 3/4 inches wide.  Leaves occur on relatively long (1 to 2 inches) petioles.

Flowers:  Showy, bright yellow, and approximately 1 inch in diameter.  Individual flowers are composed of outer yellow ray flowers that are from 1 to 1 1/2 inches long and 8 to 17 mm wide.  Flowering heads are surrounded by outer bracts that are green and approximately 1/4 to 3/4 inches long.
Identifying Characteristics: Summer annual with leaves that are dissected 2 to 3 times and have showy, bright yellow flowers.  Coreopsis beggarticks seedlings are similar in appearance to those of Common Ragweed (Ambrosia artemisiifolia) and Spanishneedles (Bidens bipinnata), however the cotyledons of common ragweed are much more rounded than those of coreopsis beggarticks or spanishneedles.  Additionally, common ragweed seedlings do not have the characteristic maroon highlights on the cotyledon and leaf undersurfaces like those of spanishneedles.  Devils Beggarticks (Bidens frondosa) is also similar in appearance to coreopsis beggarticks and spanishneedles, however devils beggarticks does not have leaves that are dissected 2 to 3 times.  Coreopsis beggarticks can also be confused with spanishneedles, however coreopsis beggarticks has flowers that are much larger and more showy and leaflets that are more linear than those of spanishneedles.