Description: An aggressive herb in the aster family with showy flowers.
Life cycle: Biennial
Habitat: Grows in neutral to acidic soils. It invades open natural areas, meadows, grassy bald, disturbed areas, old pastures, roadsides, waste places, ditch banks, old fields and old pastures.
Flower: Large disk-shaped showy red-purple flower heads which contain hundreds of tiny individual flowers are 11/2 to 31/2 inches in length. 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 straw colored seeds.
Leaf: Spiny dark green coarsely lobed leaves with a smooth waxy surface and a yellowish to white spine at the tip.
Stem: Multi branched spiny stems from 1 ½ to 6 feet tall.
Root: Single tap root
The problem is….the invasive nature of this plant can lead to severe degradation of native grasslands and meadows. Grazing animals on native vegetation gives the thistle a competitive advantage.