Broom Snakeweed: perennial with bushy stems that branch upwards; leaves range in shape from linear to threadlike; dense clusters of yellow flowers form at the ends of stems.

• A. Common Mullein
• B. Showy Milkweed
• C. Larkspur
• D. Broom Snakeweed

Answer: (D)

Identifying a plant in the field comes down to matching growth form, leaf shape, and how the flowers are arranged. The description here—perennial with bushy stems that branch upward, leaves that are linear to threadlike, and dense clusters of yellow flowers at the ends of the stems—fits broom snakeweed very well. This species is known for its upright, branching habit, slender linear leaves, and yellow flower heads gathered in compact clusters at the ends of branches, which is a distinctive combination for this plant.

Common mullein has a very different look: it starts as a rosette with large, fuzzy leaves and later sends up a tall flowering stalk with a single, dense spike of yellow flowers, not small, threadlike leaves or dense clusters at stem tips. Larkspur features deeply lobed leaves and tall spikes of blue-to-purple flowers, not the slender leaves or yellow heads described. Showy milkweed has broader leaves and pinkish to white flower clusters, arranged differently than the dense yellow heads at stem tips. So the described plant aligns best with broom snakeweed.