Native Americans used Asarum caudatum medicinally to treat headaches, intestinal pain, knee pain, indigestion, boils, tuberculosis, and colic, and as a general tonic (D. E. Moerman 1986).
Provided is a general description of British Columbia wildginger characteristics that may relate to its fire ecology. Keys for identification are available: [26,27,34,37,46,48].
British Columbia wildginger is a short-statured, native perennial that is considered evergreen in most of its range. British Columbia wildginger produces slender, elongate, shallow rhizomes that allow for a spreading to highly-matted growth form. The heart- or kidney-shaped leaves occur 2 per node and measure 1.5 to 4 inches (4 -10 cm) long by up to 6 inches (15 cm) wide. A ginger odor is released through rubbing or crushing the leaves. Fruits are capsules containing several seeds. Seeds have a fleshy appendage and are dispersed by ants. British Columbia wildginger produces rhizomes that grow to just 0.7 inches (18 mm) long [10,20,26,27,34,48]. Cates [12] indicates that 2 British Columbia wildginger morphological types exist. One type flowers earlier, produces more seeds and tends to be found on wetter sites while the other type flowers later, produces less seed, and often occupies drier sites.
Fire adaptations: To date, (2004) no primary literature has been located that specifically addresses British Columbia wildginger's fire adaptations. British Columbia wildginger was found the 1st postburn year following a high-severity fire in northern Idaho [59]. In a decade-long study following a high-severity, stand-replacing fire in western redcedar-western hemlock forests of northern Idaho, British Columbia wildginger was classified as a residual colonizer, establishing from on- or off-site seed or fruit [60,61]. However, British Columbia wildginger has rhizomes that sprout new individuals [27,48], and while no study specifically states that British Columbia wildginger sprouts from rhizomes following disturbance or fire, this adaptation should not be overlooked as a potential postdisturbance or POSTFIRE REGENERATION STRATEGY.
FIRE REGIMES: The fire regime for British Columbia wildginger is dictated by the overstory community. Prior to 1900, grand fir communities are characterized as having mixed and stand-replacing FIRE REGIMES [3]. Smith [56] highlights the extreme variation within grand fir habitat types. This includes frequent fires that create persistent shrub communities and areas where no evidence of past fire has been located [56]. Western hemlock/British Columbia wildginger habitat types experienced infrequent, high-severity fires at 100 to 200 year intervals [38]. Presettlement FIRE REGIMES in northern Idaho for the western redcedar and western hemlock/British Columbia wildginger habitat types have been described as stand replacing with long fire return intervals that have been attributed to the moist understory conditions and the build-up of continuous fuels [56]. However, small understory burns have been described as well.
The following list provides fire return intervals for plant communities and ecosystems where British Columbia wildginger may be found. It may not be inclusive. Find further fire regime information for the plant communities in which this species may occur by entering the species name in the FEIS home page under "Find FIRE REGIMES".
Community or Ecosystem Dominant Species Fire Return Interval Range (years) silver fir-Douglas-fir Abies amabilis-Pseudotsuga menziesii var. menziesii > 200 grand fir Abies grandis 35-200 [3] tamarack Larix laricina 35-200 [47] western larch Larix occidentalis 25-350 [4,8,16] western white pine* Pinus monticola 50-200 Pacific ponderosa pine* Pinus ponderosa var. ponderosa 1-47 [3] interior ponderosa pine* Pinus ponderosa var. scopulorum 2-30 [3,7,36] Rocky Mountain Douglas-fir* Pseudotsuga menziesii var. glauca 25-100 [3,5,6] coastal Douglas-fir* Pseudotsuga menziesii var. menziesii 40-240 [3,41,50] California mixed evergreen Pseudotsuga menziesii var. menziesii-Lithocarpus densiflorus-Arbutus menziesii < 35 [3] redwood Sequoia sempervirens 5-200 [3,19,62] western redcedar-western hemlock Thuja plicata-Tsuga heterophylla > 200 western hemlock-Sitka spruce Tsuga heterophylla-Picea sitchensis > 200 mountain hemlock* Tsuga mertensiana 35 to > 200 [3] *fire return interval varies widely; trends in variation are noted in the species reviewBritish Columbia wildginger occupies moist, shady woodlands of low- to mid-montane regions [27,32,34].
Climate: The winter climate where British Columbia wildginger occurs has been described as mild; temperatures are normally 15 to 25° F (8-14° C) [14]. Precipitation falls predominantly in the winter and spring months as rain or deep snow at the higher elevations, and humidity levels are typically high. Summers months are dry; July and August normally receive less than 1 inch (25 mm) of rainfall for the month. Dry thunderstorms are more common during these times [14].
Soils: Silt to loam soils are described for most habitat types characterized by British Columbia wildginger [14]. Depths from 8 to 73 inches (20-185 cm) were reported and pH ranged from 4.5 to 7.1.
Oregon and Washington: British Columbia wildginger is common within the Douglas-fir-western white pine communities of the Blue Mountains. These communities occur from 4,921 to 6,562 feet (1,500-2,000 m) elevation and receive on average 25 to 45 inches (635-1,140 mm) of precipitation annually [13]. The western hemlock/British Columbia wildginger plant association occurs at low to moderate elevations (2,200 to 3,400 feet (670-1,036 m)), on north, west, and southwest aspects with moderate slopes (1-57%). Western hemlock/vine maple (Acer circinatum) /British Columbia wildginger plant associations occur between 2,140 and 2,730 feet (652-832 m) elevation, on most aspects with 1-48% slope, and on less moist soils than western hemlock/British Columbia wildginger [38].
Northern Idaho: The western hemlock/British Columbia wildginger habitat type, considered the most productive of the western hemlock areas, can be found on any slope or landform from 2,200 to 5,000 feet (670-1,520 m) [14]. Western redcedar/British Columbia wildginger habitat types are considered highly productive and occur on all aspects and landforms, primarily occupying moderate slopes (8-25 degrees) between 2,200 and 5,200 ft (670-1,590 m). Within cedar-hemlock forests, British Columbia wildginger occurred with higher frequency when tree cover was greater than 41% than when tree cover was less than 10% and had significantly higher frequency when shrub cover was less than 30% [42]. The grand fir/British Columbia wildginger habitat type occurs at elevations as low as 4,200 feet (1,280 m) and as high as 6,000 feet (1,829 m) [14,18]. The Pacific yew/British Columbia wildginger habitat type occurs on warmer sites and on shallower soils than the grand fir/British Columbia wildginger habitat type [15].
As the dominant forb in the understory of the late seral spruce-fir forest, British Columbia wildginger may be important in some aspect of the northern Idaho pocket gopher's survival. The abundance of pocket gophers in northern Idaho was found to be greatest in early- and late-seral spruce-fir forests [53,54]. The author suggests that the preference for these seral stages may indicate a preference for the vegetation that defines these seral stages [53,54]. More supporting evidence comes from a pollination study in northern California where Lu [39] had to tailor the study around rodents that fed on numerous mature British Columbia wildginger fruits. The types of rodents were not identified, however.
Western hemlock/British Columbia wildginger sites do not provide for livestock grazing; just 50 lbs/acre of herbage is produced annually [38].
Palatability/nutritional value: British Columbia wildginger is palatable to slugs [12].
Cover value: No information is available on this topic.
British Columbia wildginger is a common understory species and is used to identify habitat types
within western redcedar (Thuja plicata), western hemlock
(Tsuga heterophylla), grand fir (Abies grandis), and Pacific yew
(Taxus brevifolia) forest types [14,15,28]. British Columbia wildginger is also found in western
white pine (Pinus monticola), Douglas-fir (Pseudotsuga menziesii)
[13], western larch (Larix occidentalis) [22,23], white fir (A. concolor)
[51], and red alder (Alnus rubra) [11] communities.
Shrub and subshrub species commonly found with British Columbia wildginger include: baldhip rose (Rosa
gymnocarpa), big huckleberry (Vaccinium membranaceum), Rocky Mountain maple
(Acer glabrum), twinflower (Linnaea borealis) and Oregon boxwood
(Paxistima myrsinites). Forbs commonly associated with British Columbia wildginger include:
ladyfern (Athyrium filix-femina), devilsclub (Oplopanax horridus),
queencup beadlily (Clintonia uniflora), pioneer violet (Viola glabella),
western sword fern (Polystichum munitum), oak fern (Gymnocarpium dryopteris),
Idaho goldthread (Coptis occidentalis), drops of gold (Disporum hookeri),
American trailplant (Adenocaulon bicolor), and threeleaf foamflower
(Tiarella trifoliata) [14,32,38,44].
British Columbia wildginger is recognized as a dominant species in many vegetation classifications including:
ID: [1,14,18,28,45,65]
OR: [13]
WA: [13,38]
Western regions: [2]
British Columbia wildginger's postfire response depends on the severity on the fire and its effect on the overstory community. Following moderate severity slash burns in a clearcut Douglas-fir community near Oakridge, Oregon, burned and unburned plots were compared [58]. British Columbia wildginger, an uncommon understory species in this community, was not found on burned plots sampled 11 to 16 years following the fires. It did occur on clearcut, unburned sites, where vine maple contributed to greater shading of the area [58]. Similarly, in a study of single and multiple broadcast burns that removed all tree cover except an occasional western larch, British Columbia wildginger was significantly (p = .05) more frequent on sites that had not burned [42]. Data were not provided about time since or between burns of the sites.
The 1st year following a high-severity, stand-replacing fire in northern Idaho forests, British Columbia wildginger was found on just 1 of 21 postburn plots [59]. The British Columbia wildginger found was a seedling and did not flower that 1st postburn year [59]. In a study designed to determine successional pathways following disturbance within the grand fir/British Columbia wildginger habitat type, British Columbia wildginger was found in all but the earliest seral communities following fire and clearcutting that produce fires of varying severities [24].
British Columbia wildginger produces rhizomes and seeds and both are a means of reproduction. Muir [43] found that asexual reproduction was less costly to wildginger (Asarum spp.) than sexual reproduction. Reproducing sexually requires that energy be transferred from growth and nutrient storage to flower and seed production [43].
Breeding system: British Columbia wildginger flowers are both perfect and protogynous [39]. Autogamy is predominant [39].
Pollination: Cross-pollination was found to be rare in northern California populations and was thought to be due to the lack of nectar and fragrance produced by British Columbia wildginger flowers [39].
Seed production: The fruit capsules of wildginger (Asarum spp.) begin dropping seeds in early summer [52].
Seed dispersal: The appendage of British Columbia wildginger seed is rich in an ant-attracting oil [48]. Ants carry the seed to their nests, feed on the seed appendages, discard the seed in piles, and effectively disperse British Columbia wildginger seed.
Seed banking: No information is available on this topic.
Germination: No information is available on this topic.
Seedling establishment/growth: British Columbia wildginger has been described as slow growing [52]
Asexual regeneration: British Columbia wildginger has rhizomes and often forms mats of vegetation [27,48]. Sprouting from rhizomes in relation to disturbance was not discussed in the literature.
British Columbia wildginger can be present in most successional communities. This species was the most dominant forb species in 80+ year old stands of spruce-fir forests of northern Idaho [53,54]. British Columbia wildginger has been described as shade tolerant [27,34,48] and as a climax species by some [29,45].
The available literature suggests that British Columbia wildginger is commonly absent from very early seral communities. British Columbia wildginger is rarely found in clearcut areas of northern Idaho conifer forests [35], suggesting an intolerance of very early seral conditions. It is also common to find British Columbia wildginger associated with western larch and western white pine, both of which are present in a variety of seral stages [22,23]. Researchers [24] attempted to determine successional pathways within the grand fir/British Columbia wildginger habitat type following a variety of disturbances. Areas that had been clearcut and broadcast burned producing mid- to high-severity fires were not colonized by British Columbia wildginger until after progressing through the herbaceous structural stage. In some areas following the same treatments, British Columbia wildginger was not present until the community had progressed through the sapling or pole stage of development. Yet, when areas were burned in low- to mid-severity wildfires and the overstory community remained intact, British Columbia wildginger persisted [24]. This suggests British Columbia wildginger is present in those seral stages that contain some overstory canopy but is not a pioneer species.
The scientific name of British Columbia wildginger is Asarum caudatum Lindl. (Aristolochiaceae)
[25,26,29,33,36,45,47].
When literature is cited that refers to Asarum spp. by
genus only and does not specify species, it is indicated as wildginger (Asarum
spp.).
Asarum caudatum (British Columbia wild ginger, western wild ginger, or long-tailed wild ginger) is a plant native to rich moist forests of western North America. It has heart-shaped leaves and a three-lobed purplish flower.
Growing from a long rhizome, the reniform (kidney/heart-shaped) leaves range from 2–10 centimetres (3⁄4–4 inches) in length. The leaves are found in colonies or clusters as the rhizome spreads, forming mats.[3] The leaves emit a ginger aroma when rubbed.[4] Blooming from April to July (about a month earlier in British Columbia),[4] the flower sits at the end of a 15 cm (6 in) leafstalk, often on the ground, hidden by the leaves.[5] The flowers are hirsute (hairy), cup-shaped, and brown-purple to green-yellow, terminating in three, long, gracefully curved lobes.[3][5]
Similar species include A. hartwegii, A. lemmonii, and A. marmoratum.[5]
Caudatum comes from the Latin cauda, meaning tail.[6] This refers to the tail-like shape of the flower's calyx.
Asarum caudatum is found in British Columbia, Washington, Oregon, Northern California,[7] Idaho, and Montana[3] in moist, shaded environments. Its northernmost populations occur near Meziadin Lake.[8] It is a typical herb found in the understory of mixed conifer forests under 670 metres (2,200 ft) in elevation, and is often a dominant plant.[9][10]
A. caudatum reproduces rhizomatously, meaning many mats are formed by one clonal plant connected by a rhizome. It can also reproduce sexually, with its seeds dispersed by ants. The flowers are pollinated by flies. However, cross-pollination is rare. Ants are attracted by a fatty appendage attached to the seed.[11] The ants carry the entire package back to their colonies. The seed is often dropped outside the nest once the ant realizes only the appendage is edible. Due to the costs of producing seeds with an appendage to attract ants, it is more energetically favorable for the plant to reproduce rhizomatously.[4]
Asarum caudatum is not listed a species of concern. However, the habitat in which it is native is threatened in some regions by logging and other land uses.
Members of the family Aristolochiaceae contain aristolochic acid, which has been recognized as a carcinogen.[12]
The root is edible.[13] Native Americans used the plant for various medicinal purposes.[13]
Some describe using A. caudatum as a ginger substitute[5] and as a tea with medicinal properties. In a study on its effects on fungus, A. caudatum had antifungal properties when tested against nine fungal species.[14]
Asarum caudatum (British Columbia wild ginger, western wild ginger, or long-tailed wild ginger) is a plant native to rich moist forests of western North America. It has heart-shaped leaves and a three-lobed purplish flower.
