Musk thistle (Nodding thistle, Nodding plumeless thistle)
Carduus nutans is usually a biennial, requiring 2 years to complete a reproductive cycle. However, it may germinate and flower in a single year in warmer climates. Seedlings may emerge at any time from spring to late summer and develop a rosette. Plants overwinter in the rosette stage, sending up a multi-branched flowering stem in mid spring of their second year.
Mature plants range in height from 1–1.5 metres (3.3–4.9 ft) tall and have multi-branched stems. Musk thistle has sharply spiny stems and leaves. The stem is cottony/hairy. The plants develop a rosette, with large leaves 30–60 centimetres (12–24 in) long
The leaves are dark green, coarsely bipinnately lobed, with a smooth, waxy surface and sharp yellow-brown to whitish spines at the tips of the lobes.They are more or less hairy on top, and wooly on the veins below.