This not very robust number of populations was anticipated to dwindle in the 1990s. Two populations exist on islands off the southern coast of Vancouver Island, British Columbia. The eight Washington populations are located as follows: one population south of Olympia in Thurston County, five populations on Whidbey Island in Island County, one population on San Juan Island in San Juan County, and one population on Lopez Island in Island County. levisecta is now known from ten extant populations in open grasslands distributed throughout three counties in Washington and two islands in British Columbia. Golden paint-brush historically occurred in the grasslands and prairie of the Willamette Valley, but the species has been extirpated by habitat destruction from all of its Oregon sites.Ĭ. Housing developments currently occupy the site. The area around the type locality at Mill Plain, Washington, was converted to pasture and orchards some time after the plant was first collected there in 1880. A 1984 status assessment of this species found the plant extirpated from more than 20 historic sites, many of them eliminated due to conversion of habitat through agricultural, residential, and commercial development. Golden paintbrush has been reported from more than 30 historical sites in the Puget-Willamette Trough of Oregon, Washington, and British Columbia, Canada.
Annual precipitation averages 31-53 in (78.8-134.6 cm) in the Puget-Willamette Trough. Western Oregon, Washington, and southern Vancouver Island have a maritime climate that is characterized by wet, mild winters and cool, relatively dry summers. Frequent and low intensity fires can be important in maintaining habitat for plant species such as golden paintbrush, as research has shown that periodic fires in the Puget Trough have been historically instrumental in maintaining native grassland habitat by limiting successional encroachment of trees and shrubs. rubra, Camassia quamash, Holcus lanatus, Achillea millefolium, Pteridium aquilinum, Vicia spp., and Bromus spp. Associated species include Festuca idahoensis, F. Most populations occur on glacially derived soils, either gravelly glacial outwash or clayey glacio-lacustrine sediments. Golden paintbrush occurs in open grasslands around the periphery of the Puget Trough, at elevations below 328 ft (100 m). Experimentally designed sampling surveys have been conducted where individual plants were tagged and counted perhaps this will resolve some of the confusion over census methodology. Population estimates have therefore ranged widely from year to year, and they will probably continue to do so until a consistent counting approach can be defined and upheld. To add to the difficulty in obtaining reliable population data, researchers have used a variety of census methods over the years. This plant tends to grow in clumps, one genetic individual may consist of one to 15 stems, and the number of stems per plant varies from site to site. Several characteristics of this taxon make it difficult to determine accurate counts of it when surveying in the field. Greenhouse experiments indicate, however, that it does not require a host to survive and flower. The species may be semiparasitic like other members of the genus Castilleja, possibly requiring a host plant for seedling development in its native habitat.
It is distinguished from the other Castilleja species within its range by brilliant golden to yellow floral bracts, although the plant is less conspicuous when not flowering. Each has a deeply cleft calyx 0.6-0.7 in (1.5-1.8 cm) long and a corolla 0.8-0.9 in (2-2.3 cm) long, with a slender galea (concave upper lip) three to four times the length of the unpouched lower lip. The flowers, which appear from April to June, are mostly hidden by the overlapping bracts. The lower leaves are entire and narrowly pointed the upper leaves are broader, usually with one to three pairs of short lateral lobes on the distal end.
Golden paintbrush typically has one to 15 erect to spreading unbranched stems, reaching a height of 12 in (30.5 cm), and is covered with soft, sticky hairs. Golden paintbrush, Castilleja levisecta, is a perennial herb of the snapdragon family (Scrophulariaceae). Open grasslands around the periphery of the Puget Trough.Ĭompetition with other plants, habitat modification or conversion, road maintenance, trampling, collectors. Perennial herb with brilliant golden to yellow floral bracts.
0 kommentar(er)
