Rush skeletonweed is a perennial that grows 1 to 4 feet (0.30-1.20 m) feet tall. The plant has a deep, extensive root system and stems with distinctive hairs (trichomes). Four to six inches (10-15 cm) up the stem, coarse hairs bend downward and the stem is smooth above
LEAVES:
Sharply-toothed leaves form a rosette which withers as the flower stem develops. Other leaves up the stem are inconspicuous, narrow and entire. The leaves and stems exude a milky latex when cut or damaged.
FLOWERS:
The flower heads are scattered on the branches. They are approximately 3/4 inch (2 cm) in diameter and have 7 to 15 yellow, strap-shaped flowers. Flowers and the pale, brown to nearly black, eighth-inch long (2 mm)
SEEDS:
Seeds are produced mid-July through frost. The seed is ribbed with tiny scaly projections on top and a long beak with numerous soft white bristles at one end.
OTHER:
Rush skeletonweed is an introduced Eurasian species which has infested several million acres in Idaho, Oregon, Washington and California. It inhabits well-drained, light-textured soils along roadsides, in wildlands, grain fields and pastures. It becomes established most easily in disturbed soils and is very difficult to control once it becomes established.
KEY CHARACTERS:
Rosettes resemble those of a dandelion, however, stems have red hairs at their base.
Yellow flowerheads, less than one inch wide. The strap-shaped petals have a flat end with distinct lobes.