[Hawkweeds: The Genus Hieracium in the Columbia River Gorge of Oregon and Washington]

White Hawkweed, White-flowered Hawkweed

Hieracium albiflorum

Synonyms: Chlorocrepis albiflora, Hieracium helleri, Hieracium occidentale, Hieracium siskiyouense

White Hawkweed, White-flowered Hawkweed: Hieracium albiflorum (Synonyms: Chlorocrepis albiflora, Hieracium helleri, Hieracium occidentale, Hieracium siskiyouense)

The photo above shows a close-up of the flower head of white-flowered hawkweed as photographed at about 4100' at the southeastern corner of Mt. Adams.......July 10, 2005. This is the only white-flowered hawkweed species in the Pacific Northwest. Note the thin, black bristles on the involucral bracts and minute glands that pepper the surface of the greenish involucral bracts and peduncle.

Characteristics:

White-flowered hawkweed is a wildflower with single stems, sometimes leafless or with reduced stem leaves to 100 cm in height. The stems are more strongly haired towards the base. The basal leaves are oblanceolate, narrowed to a petiole, with moderately long hairs. The leaf margins are entire to wavy and individual leaves range from 4-15 cm long and 1.2-4.5 cm wide. The leaves of the upper stems are sessile and much reduced in size.

The inflorescence is a corymb, with several to many small flower heads. The rays are white or creamy, with 13-34 flowers. The involucres range from 6-11 mm high and are narrow in outline and blackish-green in color. The involucral bracts are variable in texture, ranging from slightly glandular to hairy or nearly hairless.


Habitat:

White-flowered hawkweed is a plant of open woods or moist to dry, open hillsides.


Range:

White-flowered hawkweed is found from the Yukon to Saskatchewan, and south to California and Colorado.

In the Columbia River Gorge, it is found between the west end of the gorge and The Dalles between the elevations of 100'-4600'.


White Hawkweed, White-flowered Hawkweed: Hieracium albiflorum (Synonyms: Chlorocrepis albiflora, Hieracium helleri, Hieracium occidentale, Hieracium siskiyouense)

The photo above shows the inflorescence of white-flowered hawkweed as photographed at about 4100' at the southeast corner of Mt. Adams........July 10, 2005.

White Hawkweed, White-flowered Hawkweed: Hieracium albiflorum (Synonyms: Chlorocrepis albiflora, Hieracium helleri, Hieracium occidentale, Hieracium siskiyouense)

The photo above shows the white ray flowers of white-flowered hawkweed as photographed at about 4100' at the southeastern corner of Mt. Adams.......July 10, 2005. Note the squared-off, fringed tips to the rays.

White Hawkweed, White-flowered Hawkweed: Hieracium albiflorum (Synonyms: Chlorocrepis albiflora, Hieracium helleri, Hieracium occidentale, Hieracium siskiyouense) - White Hawkweed, White-flowered Hawkweed: Hieracium albiflorum (Synonyms: Chlorocrepis albiflora, Hieracium helleri, Hieracium occidentale, Hieracium siskiyouense)


Paul Slichter