Cirsium oleraceum, the cabbage thistle or Siberian thistle, is a species of thistle in the genus Cirsium within the sunflower family, native to central and eastern Europe and Asia, where it grows in wet lowland soils.Cirsium oleraceum is a herbaceous perennial plant growing to 1.5 m tall, the stems unbranched or with only a very few branches. The leaves are broad and ovoid, with a weakly spiny margin. The flowers are produced in dense flower heads which are 2.5–4 cm diameter, pale yellow, but sometimes ...