Stylosanthes biflora

Pencil Flower has been called 'the cutest flower in all the land'.  Its genus is derived from the Greek stylo and anthos which translates to style flower.  That in turn refers to the stalk-like calyx tube that is surrounding the pistil of the flower. The common name pencil flower is also derived from the plant structure, resembling the wood on a pencil surrounding the lead.    

It is a native perennial wildflower in the legume family found in central and eastern USA in dry woods, fields and thickets. It is found throughout NC. The plant grows .5 to 1.5 feet tall and the yellow pea-like flowers bloom from late spring to fall, but rather sparsely. Bees pollinate the flowers and deer and rabbits will browse the leaves. It also serves as a host plant for the larvae of the Barred yellow (Eurema daira) butterfly. There is some variation in the leaves and flowers throughout its range.

This plant prefers acidic somewhat nutrient poor soils where competition from other plants is not an issue. Like other plants in the legume family, it has the ability to make its own nitrogen, thereby surviving where other plants may not.   It grows in full sun to partial shade and is generally found in upland rocky woodlands and savannas, bluffs, prairies, fields and particularly where sandstone is present close to the ground surface.  It is generally not used in cultivation and is hard to find but could be grown in naturalized areas.

It is sometimes confused with Desmodium and Lespedeza.  The difference is in the veins on the underside of the leaflets.  On Stylosanthes biflora, the veins are lighter in color than the leaflet, while the veins on Lespedeza and Desmodium are the same color as the leaflets.