Musk thistle (Carduus nutans)
Description: Large, spiny thistle with erect stems up to 5' in height, branching near the top of the plant. Both leaves and stems are spiny.
Life cycle: Biennial. First year plant forms a low-growing circle of leaves. Second year plant grows taller producing flowering stems.
Habitat: Grows in neutral to acidic soils. It invades open natural areas, meadows, disturbed areas, pastures, roadsides, waste places, ditch banks.
Leaf: Dark-green, coarsely lobed leaves with spines at tips of lobes. Basal leaves can be 6-8 inches in length.
Stem: Multi branched spiny stems 1.5'-6' tall.
Flower: Purple flower heads 1 to 2 inches across. Flower heads will droop to a 90-degree angle from the stem when mature hence an alternate name, "nodding thistle". Each plant may product thousands of tiny seeds with feathery attachments that enable them to float in the breeze.
Root: Long, fleshy taproot.
The problem is….invades pastures, native grasslands and meadows. Livestock will not eat it, so it has a competitive advantage in a pasture and will spread.
