Photo ©2001 Steven Thorsted
HABITAT TYPES AND PLANT COMMUNITIES:
In Oregon and Washington western rattlesnake plantain is dominant in Douglas-fir (Pseudotsuga menziesii)/tanoak (Lithocarpus densiflora)-canyon live oak (Quercus chrysolepis)/western rattlesnake plantain communities . It is an indicator species for the wild sarsaparilla (Aralia nudicaulis) phase of the subalpine fir/queencup beadlily (Abies lasiocarpa/Clintonia uniflora) habitat type in Montana .
In British Columbia, western rattlesnake plantain is a zonal plant indicator for:
Region I - Pacific coastal mesothermal forest; coastal western hemlock (Tsuga heterophylla) and coastal Douglas-fir zones
Region II - Pacific coastal subalpine forest; mountain hemlock (Tsuga mertensiana) zone
Region III - Canadian Cordilleran forest; interior western hemlock zone
Region V - Canadian Cordilleran subalpine forest; Engelmann spruce (Picea engelmannii)-subalpine fir zone 
Western rattlesnake plantain is dominant and/or constantly present in the Douglas-fir-western hemlock and the transitional Pacific silver fir (Abies amabilis)-western hemlock subzones of the Vancouver Forest District, British Columbia .
Western rattlesnake plantain also occurs with Alaska-cedar (Chamaecyparis nootkatensis), Rocky Mountain maple (Acer glabrum), and Brewer's spruce (Picea breweriana) [32,60,95].
|© 2006 Earl Nance|
GENERAL BOTANICAL CHARACTERISTICS:
This description provides characteristics that may be relevant to fire ecology, and is not meant for identification. Keys for identification are available [30,41,42,49,50,81,85,100].
Western rattlesnake plantain is a native perennial, evergreen forb arising from short creeping
rhizomes with fibrous roots. The persistent leaves are arranged in a
basal rosette. They are thick, entire, and broadly lance-shaped, 1 to 4
inches (3-10 cm) long on winged petioles. The leaves have white mottling, especially along the
mid-vein. There are 2 to 5 cauline leaves on the lower stem. The stems are stout
and stiff, glandular pubescent, and have several small membranous bracts. They
are 4 to 18 inches (10-45 cm) tall. The flowers are glandular pubescent and
borne on a 1-sided or spiraled raceme up to 5 inches (12 cm) long. The petals
and 1 of the sepals of the flower form a hood over the lip. There are as many as
30 flowers/raceme, but 10 to 15 are more common. The fruit is an
erect, pubescent capsule about 0.4 inch (1 cm) long. Seeds are very small [1,27,49,64,76,77,96].
RAUNKIAER  LIFE FORM:
Western rattlesnake plantain regenerates from rhizomes and seeds .
Pollination: Bumble bees are the most common pollinators of western rattlesnake plantain. Halictid bees and syrphid flies were observed hovering near Goodyera spp. in northern Michigan. The insects sometimes landed on the flowers but were never seen bearing pollinia. The flowers of western rattlesnake plantain are protandrous, making self-pollination unlikely. Pollination occurs as the bees work their way from the bottom of the inflorescence to the top, removing pollinia from younger, upper flowers in the male stage, then flying to another inflorescence and depositing pollen on lower, older flowers in the female stage [1,55].
Some flowers in the orchid family are nectarless; however, western rattlesnake plantain flowers contain nectar. Nectar increases the chance for successful pollination because pollinators are encouraged to make repeat visits [1,73].
Breeding system: Barriers that restrict interbreeding among species are generally weak in Goodyera spp., making hybridization common in communities with multiple Goodyera species . Western rattlesnake plantain does not self pollinate in the field, however, because the flowers are protandrous. Flowers of western rattlesnake plantain were self-compatible when hand pollinated in a greenhouse study, but showed decreased fertility .
Seed production: There are many seeds per capsule (i.e. 4,874 seeds from 10 capsules) .
Seed dispersal: The minute seeds of western rattlesnake plantain are wind dispersed [1,54].
Seed banking: A seed bank study in Oregon found no viable western rattlesnake plantain seed in soils where western rattlesnake plantain grew . Further studies are needed on seed banking in western rattlesnake plantain.
Germination: In greenhouse experiments the optimum temperature for germination of western rattlesnake plantain seeds was 77 °F (25 °C) [5,19].
Seedling establishment/growth: Germinating Goodyera spp. seeds 1st produce slow-growing protocorms (cell masses that develop during orchid germination) that develop rhizoids (root-like structure lacking conductive tissues), and then develop scale-like leaves after several months of growth . Greenhouse studies indicate that once a seed has germinated, it can take up to 1 year before leaves are present and 2.5 years before the plant is fully mature .
Vegetative regeneration: Western rattlesnake plantain rapidly regenerates from rhizomes .SITE CHARACTERISTICS:
|State, Region, Province||Site Characteristic|
|Alaska||mossy forests, young climax forests [26,52]|
|Arizona||north-facing slopes; 8,900 feet (2,700 m) |
|California||dry forest floor, below 5,500 feet (1,700 m) |
|California||dry coniferous forest, in decomposing leaf litter; 1,600 to 7,200 feet (500-2,200 m) |
|Colorado||in duff on fairly dry forest floors [99,100]|
|Idaho||dense woods; 5,000 to 7,200 feet (1,500-2,200 m) |
|Montana||open or deep forests, mossy habitats from valleys to subalpine zones |
|Oregon||cool, moderately dry to moist, mixed conifer sites at all elevations up to subalpine [78,96]|
|Utah||mountain communities at 6,200 to 10,000 feet (1,900-3,100 m) |
|Great Lakes States||dry or moist hardwood or coniferous forests |
|Pacific Northwest||dry to mossy or damp, open to dense forest |
|Southwest||undisturbed forest floor of mixed conifer forests; 8,000 to 9,500 feet (2,400-2,900 m) |
|British Columbia||moderately dry, shady submontane to subalpine areas |
|Nova Scotia||damp mixed forests on slopes and ravines |
Soils: In British Columbia, western rattlesnake plantain is an indicator of nitrogen-poor soils . The most common soil moisture regime where western rattlesnake plantain occurs is "dry to fresh", and the soil nutrient regime is "very poor to medium" . Western rattlesnake plantain is restricted to formerly glaciated areas in the East .SUCCESSIONAL STATUS:
On grand fir (Abies grandis) sites in western Montana, western rattlesnake plantain was prevalent in immature stands (<90 years old), where is showed 89% presence. It was most prevalent in old-growth stands (>150 years old), with 100% presence . Western rattlesnake plantain is present in early stage development Douglas-fir and subalpine fir communities in western Montana, but is much more abundant in the mid- to late-seral stages .
Western rattlesnake plantain populations in the Pacific Northwest are most frequent among mature (80-195 years) and old-growth forests (200-730 years) in Douglas-fir/western hemlock zones. Populations were present, however, in young stands (35-79 years) . Spies  and Bailey and others  also indicate that western rattlesnake plantain is found in young, mature, and old-growth Douglas-fir forests, although it is most frequent in old-growth forests. Halpern and Spies  observed that "peak development" of western rattlesnake plantain occurred in old-growth Douglas-fir.SEASONAL DEVELOPMENT:
The following table provides flowering dates for western rattlesnake plantain throughout its distribution.
|California||July to August |
|Idaho||July to August |
|Oregon and Washington||July to September |
|Great Lakes States||July to September [41,55]|
|Pacific Northwest||July to August |
|Ontario||August to September |
Fire regimes: The warm, moist grand fir, western hemlock, and western redcedar (Thuja plicata) habitat types of western Montana, where western rattlesnake plantain widely occurs, are diverse and highly productive stands with variable fire frequencies and severities. In the event of drought, heavy fuel loading makes the productive sites subject to high-severity, widespread fires where stands are replaced and sites revert back to pioneer species .
The drier Douglas-fir and white fir (Abies concolor) series of the eastern Cascade Range, where western rattlesnake plantain is known to occur, have shorter fire-return intervals and lower fire severities. The cooler, wetter grand fir series and some Douglas-fir series have longer fire-return intervals and higher fire severities .
The following table provides fire return intervals for plant communities and ecosystems where western rattlesnake plantain is important. Find 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 |
|western larch||Larix occidentalis||25-350 [7,18,29]|
|Great Lakes spruce-fir||Picea-Abies spp.||35 to >200|
|northeastern spruce-fir||Picea-Abies spp.||35-200 |
|Engelmann spruce-subalpine fir||Picea engelmannii-Abies lasiocarpa||35 to >200|
|blue spruce*||Picea pungens||35-200 |
|Rocky Mountain lodgepole pine*||Pinus contorta var. latifolia||25-340 [17,18,94]|
|Sierra lodgepole pine*||Pinus contorta var. murrayana||35-200|
|western white pine*||Pinus monticola||50-200|
|Pacific ponderosa pine*||Pinus ponderosa var. ponderosa||1-47 |
|interior ponderosa pine*||Pinus ponderosa var. scopulorum||2-30 [6,13,65]|
|Arizona pine||Pinus ponderosa var. arizonica||2-15 [13,25,84]|
|Rocky Mountain Douglas-fir*||Pseudotsuga menziesii var. glauca||25-100 [6,8,9]|
|coastal Douglas-fir*||Pseudotsuga menziesii var. menziesii||40-240 [6,68,80]|
|California mixed evergreen||Pseudotsuga menziesii var. menziesii-Lithocarpus densiflorus-Arbutus menziesii||<35|
|canyon live oak||Quercus chrysolepis||<35 to 200 |
|redwood||Sequoia sempervirens||5-200 [6,35,93]|
|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 |
Stickney [89,90] lists western rattlesnake plantain as a "nonsurvivor" after a high-severity wildfire in a western larch-Douglas-fir forest in northwestern Montana. Western rattlesnake plantain, characteristic of nearby unburned areas, was not observed on burned sites after the high-severity Tillamook wildfires in Douglas-fir, western hemlock, and western redcedar forests in northwestern Oregon. The fires burned in 1933, 1939, and again in 1945. Data were recorded during the summers of 1955 and 1956 . A mixed-severity wildfire in a Douglas-fir forest of eastern Washington reduced western rattlesnake plantain percent cover to 0%. Before the fire the percent cover was 1% . Halpern and Spies  reported that populations of western rattlesnake plantain among Douglas-fir forests of the H.J. Andrews Experimental Forest, Oregon, were eliminated from all soil disturbance classes including disturbed but unburned, lightly burned, and heavily burned.
Western rattlesnake plantain declined following clearcutting, clearcutting with slash treatments, and wildfire in a subalpine fir/beargrass (Xerophyllum tenax) habitat type in west-central Montana. Slash treatments resulting in western rattlesnake plantain decreases were broadcast burning of logging slash and pile burning following mechanical scarification . Frequency of western rattlesnake plantain decreased in Douglas-fir and tanoak communities after logging, and frequency continued to decrease to 0% after the high-severity Biscuit Fire in southwestern Oregon . On subalpine fir sites in northwestern Montana, western rattlesnake plantain was present before disturbance (logging/slash piling/broadcast burning) and not present in the 1st 8 successional years . According to Marcum , western rattlesnake plantain is a "retreater" in response to clearcutting and site treatment (scarification and slash burning). Western rattlesnake plantain was not present for 17 years after these disturbances .
After the Waterfalls Canyon Fire in Grand Teton National Park, the mean frequency of western rattlesnake plantain in the 1st growing season was 10% on unburned sites, 3% on moderately burned sites, and 0% on severely burned sites . A prescribed fire on mixed-conifer study sites on the North Rim of Grand Canyon National Park, northern Arizona, escaped and burned with greater severity than expected. Western rattlesnake plantain frequency decreased significantly (p=0.001) on burned sites (33%) vs. unburned sites (83%) .
In a greenhouse study, different disturbances were initiated on soil blocks (dug from the western hemlock zone of the H.J. Andrews Experimental Forest) to determine the response of buried propagules to disturbances. Treatments included 0 to 3 combinations of removing shade, churning the soil, burning dry litter on top of the soil for ~30 seconds, and an undisturbed control. Three western rattlesnake plantain sprouts were recorded on the undisturbed plots, and 1 sprout was recorded on the plot that was shaded/churned/burned. No sprouts were observed on any other treatments: full sun/intact/unburned, shade/intact/burned, shade/churned/unburned, sun/intact/burned, sun/churned/unburned, and sun/churned/burned .
Hamilton's Research Paper (Hamilton 2006b) provides further information on prescribed fire and postfire response of plant species including western rattlesnake plantain.FIRE MANAGEMENT CONSIDERATIONS:
Palatability/nutritional value: No information is available on this topic.
Cover value: No information is available on this topic.VALUE FOR REHABILITATION OF DISTURBED SITES:
Production of western rattlesnake plantain decreased on grazed vs. ungrazed plots with 18.80 kg/ha and 34.10 kg/ha, respectively. The study area was a Douglas-fir/ninebark (Physocarpus malvaceus) habitat type on the University of Idaho Experimental Forest .Western rattlesnake plantain is negatively affected by harvesting. It was consistently found on uncut Douglas-fir sites of the western Cascade Range in Oregon and not found after logging . Gashwiler  states that western rattlesnake plantain survival is difficult or impossible under clearcut conditions. In western Washington and western Oregon, western rattlesnake plantain was extirpated from all harvested plots sampled. Plots were monitored for >25 years after harvest . In southern Washington's western hemlock zone, the relative change in cover of western rattlesnake plantain in harvested areas vs. forest aggregates was significantly (p=0.002) lower 2 years after treatment compared to pretreatment cover.
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