Birdsfoot trefoil is a moderately long-lived herbaceous perennial legume. It has a well developed, branching, tap-like root with side roots near the soil surface. Most cultivars are erect and grow to a height of 2 to 3 feet. The stems are slender, branch well, and are moderately leafy. Leaves are smooth and consist of 5 leaflets. The bloom is made up of a cluster of bright yellow flowers arranged in a whorl at the end of the flowering stems. When ripe, the brown seed pods extend outward from the stalk and look like a bird’s foot. The plant remains green and succulent during and after seed ripening. There are an average of 375,000 seeds per pound.