Naked-flowered Tick Trefoil
Desmodium nudiflorum /Pea Family
You don't have to find the seeds of this plant, they will find you! The small, green, triangle-shaped seeds have small hooks that stick to your clothes, a very effective (and irritating) method of propagation! "Nudiflorum" means naked-flower. It is in the Pea Family.
Where seen: Oak Ridge Greenways, Great Smoky Mountains NP, Frozen Head SP, House Mountain SNA, Warriors' Path SP