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Z. v. var. gramineus Rybd. [13,22,51,58,66,114], grassy meadow deathcamas
Z. v. var. venenosus S. Wats. [22,51,58], meadow deathcamas
In this review, "meadow deathcamas" refers to the species as a whole. Zigadenus venenosus var. venenosus is referred to as the "typical variety," and " grassy deathcamas" refers to Z. v. var. gramineus.SYNONYMS:
Meadow deathcamas is a perennial [18,22,71,72], cool-season forb [56,61,71,88,109,110]. It grows from 6 to 28 inches (15-70 cm) in height [22,51,59,74,83,84,114]. Individual plants produce a single, erect, unbranched, sparingly leafed stem [88,92,104]. Meadow deathcamas leaves are grass-like, mostly basal, 4 to 12 inches (10-30 cm) long, and 2-10 mm wide [18,22,51,74,83,84,92,104,114]. The typical variety and grassy meadow deathcamas are primarily differentiated by a raceme or panicle inflorescence. The typical variety commonly bears several to many flowers on a 2 to 8 inch (5-20 cm) long terminal raceme [22,29,46,50,51,59,84,104,105]. Grassy meadow deathcamas usually has a terminal panicle [29,114]. Meadow deathcamas seeds are small, developing in a 3-cavitied capsule [22,29,74,88,104,105,114]. The bulbs are 0.5 to 1.5 inches (1-4 cm) in diameter [42,71,74,74,92] and occur 2 to 8 inches (5-20 cm) underground . Roots are short and sparse, generally penetrating less than 6 inches (15 cm) into the soil from bulb depth .
Toxicity: Both varieties of meadow deathcamas are extremely toxic [20,61,65,72,73,100,105]. This is due to the presence of zygacine, a neurotoxic steroidal alkaloid [61,72,73,100]. Dried meadow deathcamas remains toxic for at least 20 years . Research shows that meadow deathcamas does not exhibit diurnal fluctuations in zygacine [72,73]. (For information on seasonal fluctuations, see Seasonal Development.)RAUNKIAER  LIFE FORM:
Breeding system: Meadow deathcamas has perfect flowers .
Vegetative regeneration: Meadow deathcamas reproduces vegetatively via sprouting from mature bulbs [35,58] and bulb offsets [63,79].
Currently (2006), there is no information available on meadow deathcamas pollination, seed production, seed dispersal, seed banking, germination, and seedling establishment or growth. Research is sorely needed on these plant attributes.SITE CHARACTERISTICS:
Grassy meadow deathcamas commonly occurs on hills and in meadows, and to a lesser extent in open park areas and high bench lands .Climate: Meadow deathcamas occurs in several climatic zones. In the Pawnee National Grasslands, Colorado, the climate is continental, with approximately 70% of annual precipitation falling between April and August . Meadow deathcamas occurs in the hottest, driest zone found in British Columbia. The zone, a rough fescue-bluebunch wheatgrass (Festuca altaica-Pseudoroegneria spicata) community, encompasses the valley bottoms of the Thompson, Nicola, and Fraser river systems .
Extensive climatology data for Fort Lewis, Washington, where meadow deathcamas is common, are presented by Papanikolas .
Elevation: The overall elevational range of meadow deathcamas is 1,400 to 8,000 feet (420-2,400 m) [22,25,46,56,83,84,109,110]. The elevational range of grassy meadow deathcamas is 4,000 to 7,000 feet (1,200-2,100 m) .
Soil: Meadow deathcamas thrives on sandy and rocky soil [48,56,109].
A detailed analysis of soil in Fremont County, Wyoming, where grassy meadow deathcamas occurs, is presented in a review by Bayer .
Along the coast of British Columbia, meadow deathcamas occurs in kinnikinnick communities that indicate moderately to very dry soils, oneleaf foamflower communities that indicate nitrogen-medium soils, and Wallace's spikemoss communities that indicate very shallow soils .
Soil moisture: Soil moisture affects zygacine levels in deathcamas. Near Kamloops, British Columbia, soil moisture at 2.5 inches (6.5 cm) and 5.5 inches (14 cm) was significantly correlated with zygacine levels (r = -0.54 and r = -0.52, p<0.05). At 2 of 5 sites, a 45% average decrease in water was associated with a 40% increase in meadow deathcamas zygacine levels .SUCCESSIONAL STATUS:
In the foothills meadow deathcamas generally flowers in April and May. At higher elevations meadow deathcamas flowers in late June and July [56,109,110]. The flowering periods of meadow deathcamas at several locations are presented below.
|California||May to July |
|southern California||May to June |
|Nebraska||May to July |
|Nevada||April to July |
|Great Plains||May to July [42,104]|
|Pacific Northwest||May to July |
|Uintah Mountains, Utah||June to July |
The seasonal development of meadow deathcamas in a western Montana mountain grassland ecosystem at 7,100 feet (2,160 m) was as follows :
|Growth stage||Time period|
Zygacine levels were evaluated during 4 stages of meadow deathcamas growth at grassland and subalpine sites near Kamloops, British Columbia. Zygacine concentrations were slightly higher in meadow deathcamas plants growing at subalpine elevations, which were 1,300 to 1,600 feet (400-800 m) higher than grassland elevations, compared to plants on grassland. At both sites, zygacine concentrations were highest during bud stage .
|Site||Stage of growth||Zygacine level
(% ± SD)
|Grassland||Vegetative||0.43 ± 0.03|
|Bud||0.46 ± 0.25|
|Bloom||0.34 ± 0.08|
|Pod||0.39 ± 0.12|
|Subalpine||Vegetative||0.51 ± 0.11|
|Bud||0.53 ± 0.17|
|Bloom||0.47 ± 0.15|
|Pod||0.32 ± 0.20|
Fire regimes: In the communities and ecosystems where meadow deathcamas is found, its occurrence is minor. In the literature, meadow deathcamas is most commonly associated with foothill rough fescue communities, where the historic fire return interval is 5 to 10 years [15,118].
The following table provides fire return intervals for plant communities and ecosystems where meadow deathcamas 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|
|California chaparral||Adenostoma and/or Arctostaphylos spp.||<35 to <100 |
|grand fir||Abies grandis||35-200 |
|bluestem prairie||Andropogon gerardii var. gerardii-Schizachyrium scoparium||<10|
|silver sagebrush steppe||Artemisia cana||5-45 [49,93,118]|
|sagebrush steppe||Artemisia tridentata/Pseudoroegneria spicata||20-70 |
|basin big sagebrush||Artemisia tridentata var. tridentata||12-43 |
|mountain big sagebrush||Artemisia tridentata var. vaseyana||15-40 [5,80]|
|Wyoming big sagebrush||Artemisia tridentata var. wyomingensis||10-70 (x=40) [112,120]|
|coastal sagebrush||Artemisia californica||<35 to <100 |
|plains grasslands||Bouteloua spp.||<35|
|blue grama-needle-and-thread grass-western wheatgrass||Bouteloua gracilis-Hesperostipa comata-Pascopyrum smithii||<35 [90,97,118]|
|blue grama-buffalo grass||Bouteloua gracilis-Buchloe dactyloides||<35 [90,118]|
|grama-galleta steppe||Bouteloua gracilis-Pleuraphis jamesii||<35 to <100 |
|cheatgrass||Bromus tectorum||<10 [91,115]|
|California montane chaparral||Ceanothus and/or Arctostaphylos spp.||50-100|
|mountain-mahogany-Gambel oak scrub||Cercocarpus ledifolius-Quercus gambelii||<35 to <100 |
|California steppe||Festuca-Danthonia spp.||<35 [90,102]|
|western juniper||Juniperus occidentalis||20-70|
|Rocky Mountain juniper||Juniperus scopulorum||<35 |
|western larch||Larix occidentalis||25-350 [4,9,24]|
|wheatgrass plains grasslands||Pascopyrum smithii||<5-47+ [90,93,118]|
|Engelmann spruce-subalpine fir||Picea engelmannii-Abies lasiocarpa||35 to >200 |
|pinyon-juniper||Pinus-Juniperus spp.||<35 |
|Rocky Mountain bristlecone pine||P. aristata||9-55 [27,28]|
|Rocky Mountain lodgepole pine*||Pinus contorta var. latifolia||25-340 [8,9,106]|
|Sierra lodgepole pine*||Pinus contorta var. murrayana||35-200|
|Colorado pinyon||Pinus edulis||10-400+ [36,41,60,90]|
|Jeffrey pine||Pinus jeffreyi||5-30|
|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 [3,7,68]|
|galleta-threeawn shrubsteppe||Pleuraphis jamesii-Aristida purpurea||<35 to <100 |
|quaking aspen (west of the Great Plains)||Populus tremuloides||7-120 [3,44,75]|
|mesquite||Prosopis glandulosa||<35 to <100 [34,90]|
|mountain grasslands||Pseudoroegneria spicata||3-40 (x=10) [2,3]|
|Rocky Mountain Douglas-fir*||Pseudotsuga menziesii var. glauca||25-100 [3,5,6]|
|coastal Douglas-fir*||Pseudotsuga menziesii var. menziesii||40-240 [3,81,96]|
|California mixed evergreen||Pseudotsuga menziesii var. menziesii-Lithocarpus densiflorus-Arbutus menziesii||<35|
|California oakwoods||Quercus spp.||<35 |
|coast live oak||Quercus agrifolia||2-75 |
|canyon live oak||Quercus chrysolepis||<35 to 200|
|Oregon white oak||Quercus garryana||<35 |
|California black oak||Quercus kelloggii||5-30 |
|interior live oak||Quercus wislizenii||<35 |
|little bluestem-grama prairie||Schizachyrium scoparium-Bouteloua spp.||<35 |
|redwood||Sequoia sempervirens||5-200 [3,34,103]|
|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 |
A December 1997 wildfire on foothill rough fescue grasslands in southwest Alberta increased meadow deathcamas cover at postfire month 6 on burn perimeters and at postfire month 18 on burn perimeter and interior sites. Meadow deathcamas cover on burn interiors at postfire month 6 was slightly less than on unburned sites. The fire was "extremely hot", with head fire intensity ranging from 10,000 to 20,000 kW/m². The average rate of fire spread (~6 miles/hr) was 1 of the greatest documented for a grassland fire in Canada. In total, the fire burned 53,370 acres (21,600 ha). Conditions were favorable in the first 2 growing seasons following the fire, with precipitation 46% above average in 1998 and average in 1999. In postfire month 6 (June 1998), meadow deathcamas cover was 0.2% on unburned sites, 0.1% on burn interior sites, and 0.9% on burn perimeter sites. In postfire month 18 (June 1999), meadow deathcamas cover was greater on both burn perimeter (1.3%) and interior (0.6%) sites compared to unburned (0.1%) sites .
In a qualitative study in southeastern Alberta, meadow deathcamas composition (% biomass relative to the community total vegetation) decreased following an August 1994 wildfire in a lowland western wheatgrass-thickspike wheatgrass-needle-and-thread grass-porcupine grass (Pascopyrum smithii-Elymus lanceolatus-Hesperostipa comata-H. spartea) community. Vegetation analysis was conducted from 1995 to 1997 during late July to early August, the period of peak standing phytomass. Pooling data from all years, meadow deathcamas composition on burned and unburned sites was 0.6% and 1.4%, respectively .
From 17 August to 24 August 1996, a lightning-initiated fire burned 4,781 acres (1,935 ha) in Mesa Verde National Park, Colorado. While no prefire data were available, percent occurrence of meadow deathcamas (relative to the total sample points) in 2 burned Utah serviceberry (Amelanchier utahensis) communities in late August to September 1997 was 33% and 17%, respectively .
A 1973 wildfire that burned from 10 August to 23 September in the Selway-Bitterroot Wilderness of Idaho had no effect on meadow deathcamas. A "trace" cover of meadow deathcamas was measured on burned and unburned sites in June 1974 and 1976 .
Meadow deathcamas cover increased following an August 2000 fire in the Craig Mountain Wildlife Area, Idaho. The site is a bluebunch wheatgrass-Sandberg bluegrass (Poa secunda) habitat type occurring on the southern aspects of 2 watersheds, China Creek and Corral Creek. In total, the fire burned 74,510 acres (30,155 ha) over a 9-day period. The 45-day period prior to the fire had below-average precipitation, but precipitation was above average in September 2000. During the 1st postfire sampling year (2002), April and May precipitation was below average. The 2nd sampling season (2003) followed months of above-average precipitation. Research conducted prior to the fire found meadow deathcamas occurred on early, mid-, and late seral sites. Meadow deathcamas cover (%) on 7 burned plots from 1999 to 2003 is shown below :
On ponderosa pine and Douglas-fir communities in the Blue Mountains of northeastern Oregon, meadow deathcamas cover and frequency in postfire year 4 were higher on thinned-and-burned sites than on thinned, prescribed burned, or unburned control sites. Meadow deathcamas was determined to be an indicator species for thinned-and-burned sites (P≤0.05). For further information on the effects of thinning and burning treatments on meadow deathcamas and 48 other species, see the Research Project Summary of Youngblood and others'  study.
Meadow deathcamas cover increased slightly during postfire year 2 on Lubrecht Experimental Forest, Montana. Prescription fires were conducted on thinned and unthinned sites in spring of 2002. Six units total were burned (3 thinned, 3 unthinned), each 22 acres (9 ha) in area. All fires were of low to moderate severity. For more information on this study, see Metlen's  Research Project Summary.
The Research Project Summary Changes in grassland vegetation following fire in northern Idaho provides further information on prescribed fire and postfire response of meadow deathcamas and other plant species.FIRE MANAGEMENT CONSIDERATIONS:
While meadow deathcamas is generally toxic to wildlife, descriptions of elk , small mammals , and mule deer  eating the forb are found in the literature.
Palatability/nutritional value: The palatability of meadow deathcamas for cattle, domestic sheep, and horses is "poor" [26,88]. Meadow deathcamas energy and protein value is rated as "poor" .
Cover value: The cover value of meadow deathcamas is generally poor for upland game birds, waterfowl, small nongame birds, and small mammals .VALUE FOR REHABILITATION OF DISTURBED SITES:
Fertilization: Nitrogen fertilization increases meadow deathcamas biomass. In a rough fescue-bluebunch wheatgrass community near Missoula, Montana, nitrogen was added at rates of 0, 50, 100, 150, and 200 kg/ha. At the 5 rates, meadow deathcamas biomass (g/m²) was approximately 0.75, 3.25, 0.75, 1.75, and 2.25, respectively .
Grazing response: Meadow deathcamas increases with overgrazing .
Herbage production: In mountain grasslands of western Montana, meadow deathcamas herbage production (air-dry) was 1 to 5 lbs./acre on southwestern exposures and 1 to 10 lbs./acre on northeastern exposures .
Livestock poisoning: Poisoning generally occurs in spring when more palatable vegetation is not available or on overgrazed ranges [88,109]. To reduce losses due to meadow deathcamas, livestock should be kept off infested ranges until adequate forage is available . Death from meadow deathcamas seen in cattle [61,100], fowl, horses, and domestic sheep. Domestic sheep losses from 500 to 2,000 animals have been reported .
Symptoms of meadow deathcamas poisoning begin with excessive salivation, soon followed by nausea and vomiting. This is followed by muscular weakness, trembling, and eventual prostration. Pulse becomes fast and weak and heart action is weakened. Heart weakening is accompanied by a struggle for breath and frequent convulsions. If animals are severely poisoned, a comatose state may precede eventual death. The comatose state varies from several hours to 2 or more days. The preceding symptoms generally apply to domestic sheep, cattle, and horses. When cattle are poisoned salivation is usually less and nausea greater [61,109,110].
In feeding experiments involving domestic sheep, the 1st symptoms of meadow deathcamas poisoning occur within 2.5 hours after ingestion, and the average duration of symptoms is 29.25 hours. The minimum toxic dose and minimum lethal dose, expressed as a percentage of the animal's weight of green plant material, is 0.4% and 2.0%, respectively .Human effects: Meadow deathcamas bulbs can cause severe illness in humans. Symptoms include gastrointestinal irritation and vasomotor collapse [56,57,61,87,110].
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