The plant is most likely a roadside wildflower belonging to the genus Stylosanthes. It could possibly be the Sidebeak pencilflower, Stylosanthes biflora, because this wildflower is commonly found along roadsides in Central and North Florida and is native to many Southern states.
Sidebeak pencilflower, a perennial, prefers acid soils and prairies or open areas. It grows in cold hardiness zones 4-9. It is an important suppler of nectar for bees and other wildlife. Sidebeak pencilflower can tolerate moist soils but can survive periods of drought too. It will grow in most any type of soil, even nutrient poor soils. Because it is in the pea or legume family it fixes or makes its own nitrogen. Sounds like the perfect plant. It will grow in some shade but loves full sun too. Sidebeak pencilflower can provide some sustenance for deer or pigs.
The pretty yellow flowers bloom from May through September and makes a good ground cover growing to about 1 foot tall with the same spread. The leaves are found in triplets around the flowers.