Black Greasewood

Reports of Sarcobatus vermiculatus from British Columbia and Texas have not been verified by us. One of the most common of western North American shrubs in alkaline habitats, S. vermiculatus grows among other shrubs or in pure stands, often to great extent, especially in the Great Basin. It is frequently codominant with Allenrolfea in areas that support little else. Other, less alkali-tolerant associates may include species of Artemisia (even A. tridentata), Atriplex, Chrysothamnus, Grayia, Krascheninnikovia, Larrea, and Suaeda. Sarcobatus vermiculatus ranks among the important western browse plants, but it has a dark side. Range animals and wildlife feed on it; the plant’s saline taste perhaps enhances its palatability. Under certain conditions, poisoning of animals, especially sheep, may result from the plant’s content of sodium and potassium oxalates (10-22% of plant dry weight). Death may occur when sheep eat large amounts of S. vermiculatus---and little or nothing else---in a short time. A notable mass poisoning of sheep occurred in 1920 when 1700 ewes in transit were unloaded and allowed to browse in a pure stand of S. vermiculatus. The next morning 1000 were dead (J. M. Kingsbury 1964). Sarcobatus vermiculatus is allegedly a phreatophyte; its taproots are said to be able to penetrate as much as 57 feet below the surface. Large communities of greasewood coincide with areas where the water table is less than 15 feet below the surface, although the plant can survive with water table depth to 25 feet (H. N. Mozingo 1987).

Plants loosely and irregularly branched, 1-2(-5) m; proximal branches rarely in contact with ground. Leaves mostly solitary on elongate shoots of current season; blade bright green to yellowish green, somewhat flattened (some shorter leaves on short shoots), (0.3-)1.5-4(-5) cm, usually glabrous or slightly pubescent, some subtending thorn. Inflorescences: pistillate flowers and staminate spikes mostly on long lateral branches with 3-9 readily visible internodes; staminate spikes typically 11-40 mm. Fruits 3-5 mm, tapered at ends; wing 0.7-1.4 cm diam. Seeds 1.8-2.1 mm. 2n = 36, 72.

Alta., Sask.; Ariz., Calif., Colo., Idaho, Mont., Nebr., Nev., N.Mex., N.Dak., Oreg., S.Dak., Utah, Wash., Wyo.; Mexico (Sonora).

Flowering spring-summer; fruiting summer-early fall.

Alkaline or saline soils in semiarid or arid plains, alkali flats, slopes, desert-shrub communities, sagebrush, saltflats, roadsides, fencerows, dry washes; 600-2400m.

Batis vermiculata Hooker, Fl. Bor.-Amer. 2: 128. 1838; Fremontia vermiculata (Hooker) Torrey; Sarcobatus maximilianii Nees

More info for the terms: seed, shrub

A review of fire effects on shrub
species described poor seed production the 1st year after burning [156]. No
information is available on black greasewood postfire seedling establishment;
more research is needed.

black greasewood

greasewood

More info for the terms: density, shrub

The following description of black greasewood provides characteristics that may be relevant to fire ecology, and is not meant for identification. Keys for identification are available (e.g. [84,85,149]).

Black greasewood is a native flowering perennial [83,107,112,116]. Its growth form is erect to low and spreading, reaching 10 feet (3 m) tall [5,15,16,47,48,66,74,96,103,107,112,116] and 3 to 6 feet (0.9-1.8 m) across [78]. The multiple branches are brittle and spinescent; the ends of smaller branches taper to sharp thorns [15,16,17,47,48,50,66,74,96,103,107,116]. Deciduous leaves are fleshy and narrow, and are 0.4 to 1.6 inches (1-4 cm) long  [15,16,17,47,48,50,66,66,74,96,103,103,107,116]. Black greasewood seeds have long wings and are 0.16 to 0.2 inch (4-5 mm) long and 0.39 inch (1 cm) wide (including wing margin) [17,66].

Where groundwater is present, maximum rooting depth of black greasewood is governed by the depth to a saturated zone. It is normally deep rooted but has some shallow roots near the soil surface [71]. Black greasewood consistently forms deep, branched taproots [68,78,116]. Branching increases toward the soil surface; taproots typically penetrate downward to the capillary fringe overlying the water table. Black greasewood is clonal and may have a number of major stem clones arising from 1 large clump. These clones in turn produce numerous taproots [68]. In a Colorado study, the majority of roots grew to a soil depth of 4.4 feet (13.5 m), though some reached the water table at 12 feet (3.7 m) [20]. In California, black greasewood roots also reached the water table, 9.8 to 16.4 feet (3-5 m) below surface [40]. Others report roots reaching 20 feet (6 m) deep [116,128]. The dense shallow root system of black greasewood has lateral roots that may extend many meters beyond the canopy [40]. At a site in Utah where the root system of a black greasewood plant was exposed, the 6-foot-tall (1.8 m) shrub had roots 18 feet (5.5 m) deep with a 3-inch (7.6 cm) diameter taproot reaching to 6 feet deep [128].

Black greasewood height, canopy coverage, and total leaf surface area are inversely related to depth to water. A study in south-central Washington compared greasewood transpiration on a site where groundwater was 23 feet (7 m) deep (site A) to a site where groundwater was approximately 42 feet (13 m) deep (site B). Black greasewood on site A had higher crown density and closer shrub spacing, shading the interior leaves and reducing water vapor transport. Black greasewood on site B, where groundwater was deeper, were more widely spaced with thin crowns. The reduction of root growth with increasing soil depth and internal resistance to water movement may also affect efficient and effective use of water by black greasewood [71]. Seasonal fluctuations in surface water also impact black greasewood; low moisture levels in the top 5 feet (1.5 m) of soil have been correlated with internal-plant stress on sites in Colorado. Interestingly, this study found little fluctuation in the water table at 12 feet (3.7 m) during the growing season, indicating little use of the groundwater by black greasewood [20].

Black greasewood occurs throughout much of western North America. It is found in Alberta and Saskatchewan; south through the western United States to northern Mexico; and east to the Dakotas, Nebraska, and western Texas [15,17,42,43,44,48,66,77,78,83,134,147,148]. Black greasewood was historically present in British Columbia, though it has been extirpated from that province [83].

Plants database provides a distributional map of black greasewood.

More info for the terms: cover, fire frequency, fire regime, forbs, frequency, fuel, grassland, moderate-severity fire, presence, seed, shrub, shrubs, stand-replacing fire

Fire adaptations: Black greasewood may be killed by severe fires, but it commonly sprouts soon after low- to moderate-severity fire [115,116,132,150,156,157]. No information is available on postfire sexual regeneration; additional research is needed on this topic.

FIRE REGIMES: Black greasewood is a constituent of several communities, but is most commonly found in desert shrub, sagebrush, plains grassland, and desert grassland types. These communities were historically subject to stand-replacing FIRE REGIMES with intervals of <100 years [108].

Stand-replacing fires in sagebrush communities occur every 20 to 70 years. Fuel loads range from very low to 2,000 pounds per acre (2,267 kg/ha), depending on the site and species. Saltbush/black greasewood stands, as well as other desert shrub types, typically experience fire intervals estimated at <35  to <100 years [108]. A review of FIRE REGIMES by Paysen and others [108] estimates fuel loads in saltbush/black greasewood communities at 250 to 750 pounds per acre (280-850 kg/ha). Fuel production in these communities varies annually, depending on precipitation. Herbage production is generally 0-500 pounds per acre (0-560 kg/ha) [108]. Historically, saltbush/black greasewood communities had sparse understories and bare soil in intershrub spaces, making these communities somewhat resistant to fire [108,156]. They may burn only during high fire hazard conditions; for example, years with high precipitation can result in almost continuous fine fuels, increasing fire hazard [108,150]. Grazing and other disturbance may result in increased biomass production due to sprouting and increased seed production, also leading to greater fuel loads [108,123]. Other desert shrub types may have as little as 40 to 100 pounds of fuel per acre (45-113 kg/ha), or as much as 1,000 pounds per acre (1,134 kg/ha) [108].

Some desert ecosystems are experiencing changes in fire regime, particularly in response to invasion by annual grasses such as red brome (Bromus madritensis ssp. rubens) and cheatgrass (B. tectorum). Cheatgrass expansion has dramatically changed FIRE REGIMES and plant communities over vast areas of western rangelands by creating an environment where fires are easily ignited, spread rapidly, cover large areas, and occur frequently [153]. Cheatgrass promotes frequent fires by increasing the biomass and horizontal continuity of fine fuels that persist during the summer lightning season and by allowing fire to spread across landscapes where fire previously restricted to isolated patches [87,136,153]. In salt-desert shrublands, the presence of cheatgrass increases fire frequency. Brooks [23] suggests greater flammability is due to higher surface-to-volume ratio of grasses compared to forbs, more continuous vegetative cover, and the ability of alien annual grasses to remain rooted and upright longer than native forbs, allowing them to persist as flammable fuels into the summer when the threat of fire is highest. Long recovery periods are needed when large-acreage fires occur in salt-desert shrub [25,28], and frequent fire may preclude establishment of desert shrubs like black greasewood.

Fire return intervals for plant communities and ecosystems in which black greasewood occurs are summarized below. 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) sagebrush steppe Artemisia tridentata/Pseudoroegneria spicata 20-70 [108] basin big sagebrush Artemisia tridentata var. tridentata 12-43 [124] mountain big sagebrush Artemisia tridentata var. vaseyana 15-40 [3,29,100] Wyoming big sagebrush Artemisia tridentata var. wyomingensis 10-70 (40**) [146,154] saltbush-greasewood Atriplex confertifolia-Sarcobatus vermiculatus < 35 to < 100 desert grasslands Bouteloua eriopoda and/or Pleuraphis mutica 5-100 [108] plains grasslands Bouteloua spp. < 35 blue grama-buffalo grass Bouteloua gracilis-Buchloe dactyloides 108,152] grama-galleta steppe Bouteloua gracilis-Pleuraphis jamesii 108] cheatgrass Bromus tectorum 110,151] curlleaf mountain-mahogany* Cercocarpus ledifolius 13-1,000 [4,125] mountain-mahogany-Gambel oak scrub Cercocarpus ledifolius-Quercus gambelii < 35 to < 100 blackbrush Coleogyne ramosissima < 35 to < 100 western juniper Juniperus occidentalis 20-70 Rocky Mountain juniper Juniperus scopulorum < 35 creosotebush Larrea tridentata 108] wheatgrass plains grasslands Pascopyrum smithii 108,111,152] pinyon-juniper Pinus-Juniperus spp. 108] Mexican pinyon Pinus cembroides 20-70 [101,139] Colorado pinyon Pinus edulis 10-400+ [57,65,86,108] interior ponderosa pine* Pinus ponderosa var. scopulorum 2-30 [2,6,90] Arizona pine Pinus ponderosa var. arizonica 2-15 [6,32,127] galleta-threeawn shrubsteppe Pleuraphis jamesii-Aristida purpurea 108] mesquite Prosopis glandulosa 99,108] mesquite-buffalo grass Prosopis glandulosa-Buchloe dactyloides 108] mountain grasslands Pseudoroegneria spicata 3-40 (10**) [1,2] *fire return interval varies widely; trends in variation are noted in the species summary
**mean

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The highly alkaline ash of burned black greasewood may increase the already alkaline soil on which black greasewood grows [75].

Rangeland seeding and invasion of exotic grasses in black greasewood communities may form a highly flammable understory, potentially increasing fire frequency [108].

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More info for the term: phanerophyte

RAUNKIAER [113] LIFE FORM:
Phanerophyte

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Topography and climate: Black greasewood thrives in many areas and plant associations from Mexico to Canada, but prefers the cold deserts north of 37o latitude [116]. Throughout its range, black greasewood grows from 500 to 8,000 feet (152-2,438 m) in elevation [78,112,116]. It is found at low to middle elevations in the intermountain region (1,000-8,000 feet) [16,18,85,107], as well as subalpine to alpine sites [83].

Annual temperatures in the shadscale zone where black greasewood is often dominant may range from a maximum of 110 oF (43 oC) to a minimum of -30 oF (-34 oC). Daily temperature fluctuations may be 21 oF in January and 56 oF during summer months [11,52]. Black greasewood grows in areas receiving 3 to 20 inches (76-508 mm) of annual precipitation [11,52,107,112]. Precipitation is unevenly distributed, with most falling during 2 periods: March through May and July through August. Summer precipitation is often in the form of cloudbursts: quick, high volume showers that provide limited available water for plants due to high runoff and evaporation in high summer temperatures [52].

Black greasewood occupies sites ranging from wetlands to deserts and open to wooded areas [83]. In the Intermountain area, it is often confined to alkali soils on alluvial areas, floodplains, dry washes, and gullies where soil moisture is high. Black greasewood often dominates desert areas where runoff waters have accumulated [18,47,76,78,84,93,103]. In the northern Great Plains, black greasewood is common on bottomland flats, adjacent gentle slopes, and stream bottoms [9,66,134].

Soils: Soils supporting black greasewood include silt-clays, clay-loams, silt-loams, or deep fine sand-loams [47,76,93,134]. Black greasewood may grow on sandy soil in the northeastern part of its range, but it is most commonly associated with heavy textured soils of high salt content (0.05-1.6%) [15,16,48,48,78,85,116,131]. Black greasewood is halophytic [20,37,48] and often associated with saline [8,16,21,36,76,78,93] and alkaline soils [21,36,78] that may have a pH of 6.2 to 9.8 [8,36,47,76,131]. Donovan and Richards [39] found that black greasewood is more stress tolerant than rubber rabbitbrush, growing better on sites high in sodium and boron. Black greasewood frequently occurs in nearly pure stands in saline conditions [15,16,48,78]. Black greasewood is not, however, an infallible indicator of high soil salt content; it also grows well on nonsaline soils [27,48,128].

On black greasewood sites, surface soil may be rich in sodium and other cations, especially immediately beneath greasewood shrubs where localized recycling occurs [71,103]. Black greasewood accumulates sodium in its leaves and creates a salt-enriched microenvironment under its canopy due to leaching of salt from shed leaves [40,114]. Soils are likely alkali-sodic in the upper stratum immediately under the plant crown, and either saline or alkali-sodic between plants and in the strata below a depth of 9 to 12 inches (23-30 cm) [47]. The accumulation of osmotically active salts facilitates black greasewood's tolerance of very saline sites. Higher leaf ion concentration can maintain lower osmotic potentials and thus maintain water uptake [40]. In one Washington study, sodium content of black greasewood leaves steadily increased from about 45 mg/g of dry matter in late April to 118 mg/g in early November [114]. Black greasewood can accumulate large amounts of leaf sodium over a range of sites from non-saline to highly saline, contributing to its success over salinity gradients. It is also able to maintain adequate uptake of N, P, K, Ca, and Mg under variable substrate combinations of nutrients and sodium [41].

The following table presents mean values (n=10) for various soil characteristics from 4 depths in a Utah black greasewood community [64]:

  Soil depth   0-6 inches (0-15 cm) 6-18 inches (15-46 cm) 18-36 inches (46-91 cm) 36-60 inches (91-152 cm) pH 8.2 8.7 8.4 8.2 total soluble salts (%) 0.29 0.82 1.03 1.19 lime (%) 13 19 19 14 permeability (in./hr) 0.25 0.12 0.16 0.31 sodium (ppm) 580 1,865 2,355 2,946 calcium (ppm) 63 88 237 1,003 magnesium (ppm) 20 47 80 166 potassium (ppm) 158 118 90 118 chloride (ppm) 788 2,425 2,894 3,557 sulfate (ppm) 140 1,323 1,412 4,244 carbonate (ppm) 0 0 1 0 bicarbonate (ppm) 587 697 546 432

Average soil nutrient contents from additional black greasewood communities in Utah are higher [24]:

percent nitrogen 0.13 phosphorus (ppm) 18.6 calcium (ppm) 9062.30 magnesium (ppm) 607.80 sodium (ppm) 1031.20 percent sodium saturation 8.64 potassium (ppm) 921.00 iron (ppm) 5.80 manganese (ppm) 8.70 zinc (ppm) 1.70 copper (ppm) 2.20

In addition to salt tolerance, black greasewood is also drought tolerant [78]. However, it may respond to severe drought with leaf drop, reduced canopy size, or increased mortality [40]. Black greasewood is intolerant of strongly acid soils [112].

Water relations: Black greasewood is phreatophytic [40,48], and its distribution is well correlated with the distribution of groundwater [103]. It is also believed to be related to the amount of exchangeable sodium and the percent of water retained at field capacity [116,131]. Black greasewood stands develop best where moisture is readily available, either from surface or subsurface runoff [27]. It is commonly found on floodplains that are either subject to periodic flooding, have a high water table at least part of the year, or have a water table less than 34 feet (10.5 m) deep [15,16,20,48,48,71,78,85]. A study of an expanding lake in Oregon found that black greasewood tolerated flooding for 40 days before negative effects were apparent. Water tables within 9.8 to 11.8 inches (25-30 cm) of the surface had no effect on black greasewood [62]. Another study, conducted in California, found that black greasewood did not survive 6 months of continuous flooding [67,68].

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This species is known to occur in association with the following cover types (as classified by the Society of American Foresters):

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SAF COVER TYPES [51]:

237 Interior ponderosa pine

238 Western juniper

239 Pinyon-juniper

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This species is known to occur in the following ecosystem types (as named by the U.S. Forest Service in their Forest and Range Ecosystem [FRES] Type classification):

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ECOSYSTEMS [63]:





FRES21 Ponderosa pine

FRES29 Sagebrush

FRES30 Desert shrub

FRES33 Southwestern shrubsteppe

FRES35 Pinyon-juniper

FRES36 Mountain grasslands

FRES38 Plains grasslands

FRES40 Desert grasslands

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This species is known to occur in association with the following plant community types (as classified by Küchler 1964):

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KUCHLER [88] PLANT ASSOCIATIONS:

K011 Western ponderosa forest

K016 Eastern ponderosa forest

K017 Black Hills pine forest

K023 Juniper-pinyon woodland

K024 Juniper steppe woodland

K032 Transition between K031 and K037

K037 Mountain-mahogany-oak scrub

K038 Great Basin sagebrush

K039 Blackbrush

K040 Saltbush-greasewood

K041 Creosote bush

K042 Creosote bush-bur sage

K051 Wheatgrass-bluegrass

K053 Grama-galleta steppe

K055 Sagebrush steppe

K056 Wheatgrass-needlegrass shrubsteppe

K057 Galleta-threeawn shrubsteppe

K063 Foothills prairie

K064 Grama-needlegrass-wheatgrass

K065 Grama-buffalo grass

K066 Wheatgrass-needlegrass

K068 Wheatgrass-grama-buffalo grass

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This species is known to occur in association with the following Rangeland Cover Types (as classified by the Society for Range Management, SRM):

More info for the terms: cover, shrub, shrubland, vine, woodland

SRM (RANGELAND) COVER TYPES [130]:

101 Bluebunch wheatgrass

107 Western juniper/big sagebrush/bluebunch wheatgrass

109 Ponderosa pine shrubland

211 Creosote bush scrub

212 Blackbush

301 Bluebunch wheatgrass-blue grama

303 Bluebunch wheatgrass-western wheatgrass

309 Idaho fescue-western wheatgrass

310 Needle-and-thread-blue grama

314 Big sagebrush-bluebunch wheatgrass

315 Big sagebrush-Idaho fescue

316 Big sagebrush-rough fescue

320 Black sagebrush-bluebunch wheatgrass

321 Black sagebrush-Idaho fescue

401 Basin big sagebrush

402 Mountain big sagebrush

403 Wyoming big sagebrush

405 Black sagebrush

408 Other sagebrush types

412 Juniper-pinyon woodland

414 Salt desert shrub

415 Curlleaf mountain-mahogany

416 True mountain-mahogany

417 Littleleaf mountain-mahogany

501 Saltbush-greasewood

502 Grama-galleta

504 Juniper-pinyon pine woodland

506 Creosotebush-bursage

508 Creosotebush-tarbush

606 Wheatgrass-bluestem-needlegrass

607 Wheatgrass-needlegrass

608 Wheatgrass-grama-needlegrass

609 Wheatgrass-grama

612 Sagebrush-grass

615 Wheatgrass-saltgrass-grama

701 Alkali sacaton-tobosagrass

702 Black grama-alkali sacaton

704 Blue grama-western wheatgrass

705 Blue grama-galleta

712 Galleta-alkali sacaton

725 Vine mesquite-alkali sacaton

Though top-killed, black greasewood sprouts quickly after fire [115,116,132,150,156,157]. However, severe fires may result in black greasewood mortality [132].

More info for the terms: cover, presence

Black greasewood is an important winter browse plant for domestic sheep, cattle, and big game animals [5,16,48,81,102]. It also receives light to moderate use by domestic sheep, cattle, mule deer, and pronghorn during spring and summer months [15,16,31,45,73,89,96,96,102,102,133,140]. Black greasewood is an important source of food for jackrabbits [50]; it is used in minor amounts by other small mammals including chipmunks, porcupines, and prairie dogs [48,116] and by birds [48] including California quail [50].

Palatability/nutritional value: Palatability of black greasewood has been rated as follows [35,122]:

  CA CO MT ND UT WY Cattle Fair-useless Poor Fair Fair Fair Fair Domestic sheep Fair-poor Fair Fair Fair Fair Fair Horses Useless Poor Fair Fair Fair Fair Pronghorn --- --- Fair Fair Fair Fair Elk --- --- Poor --- Poor Poor Mule deer Poor --- Poor Good Fair Fair White-tailed deer --- Fair Poor --- --- Poor Small mammals --- --- --- --- Fair Fair Small nongame birds --- --- --- --- Fair Poor Upland game birds --- Poor --- --- Fair --- Waterfowl --- --- --- --- --- Poor

Black greasewood may offer palatable browse, but also has high oxalate content (see below) [78]. Analysis of black greasewood ash has found high levels of salt [75]; a California study found sodium in black greasewood leaves reached up to 9.1% of dry mass [40]. A Montana study evaluating the chemical composition of range plants found black greasewood was 8.4% protein: greater than winterfat, shadscale, or big sagebrush [80]. The mean chemical composition of black greasewood browse samples from southeastern Montana is presented below [81]:

Year Protein (%) Phosphorus (%) Carotene (mcg/g) 1950-1951 8.4 0.075 9.2 1951-1952 9.0 0.087 10.4

Nutritional content of black greasewood as established by the National Academy of Sciences [106] is as follows:

---------%-----------

Browse Buds Ash 14.6 16.3 Crude fiber 23.5 9.3 Ether extract 3.4 3.3 N-free extract 37.3 36.8 Protein 21.4 34.3 Calcium 0.91 --- Phosphorus 0.18 ---

-------mg/kg-----------

    Copper 15.7 --- Manganese 25.8 --- Carotene 43.4 ---

Oxalate content: Black greasewood contains soluble sodium and potassium oxalates that may cause poisoning and death in domestic sheep and cattle if large amounts are consumed in a short time [15,16,18,55,79,94,107,126,138]. In general, oxalate concentrations in plants differ with both season and location; usually they reach a maximum in late summer and fall. Moderate amounts of oxalates appear to be readily eliminated by domestic livestock; however, large concentrations can result in the precipitation of oxalate crystals in the kidneys and urinary tract. Both the amount and time of ingestion are important determinants of whether toxic levels will be reached in the blood. Also, presence of other food in the stomach lessens the absorption rate and decreases the chance of poisoning [104]. The habit of black greasewood to grow in dense pure stands contributes to the danger of poisoning [138].

Domestic sheep have been poisoned by rapidly consuming large amounts of black greasewood leaves, which contain high levels of soluble oxalate [48,55,135]. A study of 36 black greasewood-fed sheep by Fleming and others [55] found that for each 100 pounds (45 kg) of the sheep's live weight it took 5.61 pounds (2.5 kg) of black greasewood leaves to cause death and 5.06 pounds (2.3 kg) to produce poisoning symptoms followed by recovery. Feedings of 3.88 pounds (1.7 kg) failed to result in detectable poisoning symptoms [55]. However, some authors [53,79] suggest that as little as 2 pounds (0.9 kg) of green leaves can be lethal to sheep if eaten in a short time without other feed. Three to 3.5 pounds (1.4-1.6 kg) of black greasewood leaves may be lethal to cattle [79]. The individual animal's condition appears to influence the degree of poisoning [55], and the toxicity of black greasewood leaves increases as the season advances [55,79,126]. Toxicity appears lower in the early spring, when leaves have higher water content [55]; however, young spring foliage may be more palatable and attractive to livestock, increasing the risk of over-consumption and poisoning. If black greasewood is introduced slowly to livestock, they may become accustomed to and tolerant of the oxalate content [18].

Cover value: The low-to-the-ground, rigid branches of black greasewood provide excellent cover for small mammals [48,50,134]. Black greasewood may also provide cover for mule deer [96]. Cover value of black greasewood has been rated as follows [34,35,91]:

  CO MT ND OR UT WY Pronghorn --- Fair Fair --- Fair Good Elk --- Poor --- --- Poor Fair Mule deer Good Fair Good Poor Fair --- White-tailed deer Good Fair --- --- --- Fair Small mammals Good Good --- Good Good Fair Small nongame birds Fair Good --- Good Good Fair Upland game birds --- Fair --- --- Good Poor Waterfowl --- Poor Good --- --- ---

More info for the terms: association, codominant, shrub, shrubs



Black greasewood/basin wildrye community, Lassen County, California.Photo courtesy of the PRBO Conservation Science Shrubsteppe Monitoring Program.



On saline sites black greasewood may grow in nearly pure stands [15,16,48,96] or
in association with saltbushes (Atriplex spp.) [15,128]. On less saline sites it
may occur with several other shrub species [128].
Shrubs commonly codominant with black greasewood are rubber rabbitbrush (Chrysothamnus nauseosus),
budsage (Artemisia spinescens), big sagebrush (A. tridentata),
fourwing saltbush (Atriplex canescens), and shadscale (A. confertifolia)
[7,13,38,93,96,128,141,142]. Other shrub associates include spiny hopsage (Grayia spinosa), winterfat
(Krascheninnikovia lanata), black sagebrush (Artemisia nova), and snakeweeds (Gutierrezia spp.) [96].

The following grasses are common associates and often codominant with black
greasewood: saltgrass (Distichlis spicata), basin wildrye (Leymus
cinereus), Salina wildrye (L. salinus), alkali sacaton (Sporobolus
airoides), alkali muhly (Muhlenbergia asperifolia), western
wheatgrass (Pascopyrum smithii), bluebunch wheatgrass (Pseudoroegneria spicata),
bottlebrush squirreltail (Elymus elymoides), and bluegrasses (Poa
spp.) [7,13,33,38,60,69,92,93,93,96,105,128,141,142,143,155].

In Washington, black greasewood is commonly found with spiny hopsage, big sagebrush, saltgrass, and cheatgrass (Bromus
tectorum) [71]. Black greasewood is dominant or codominant with big
sagebrush in the northern plains; other associates include shadscale,
Nuttall's saltbush (Atriplex nuttallii),
western snowberry (Symphoricarpos occidentalis), rubber rabbitbrush, fourwing
saltbush, winterfat, western wheatgrass, blue grama (Bouteloua gracilis),
slender wheatgrass (E. trachycaulus), bluebunch wheatgrass, saltgrass, Sandberg bluegrass
(P. secunda), and thickspike wheatgrass (E. lanceolatus)
[9,12,76].

In Utah and Nevada, black greasewood forms large colonies on alkali plains with creosotebush, rubber rabbitbrush, and
sagebrush (Artemisia spp.) [116]. Black greasewood is an important
component in salt-desert shrub
vegetation with shadscale, Gardner's saltbush (Atriplex
gardneri), mat saltbush (A. corrugata), fourwing saltbush, valley
saltbush (A. cuneata), winterfat, spiny hopsage, budsage, black sagebrush,
and green rabbitbrush (C. viscidiflorus). Associated grasses include Indian
ricegrass (Achnatherum hymenoides), bottlebrush squirreltail,
Sandberg bluegrass, galleta (Pleuraphis jamesii), alkali sacaton, sand dropseed (Sporobolus
cryptandrus), and blue grama [15,128].

Vegetation classifications in which black greasewood is identified as a plant community dominant include:

California [155]

Colorado [7,141,142]

Idaho [33]
Montana
[26,69,70,105]

Nevada [13,14]

New Mexico [38,59,60]

North Dakota [76]

Washington [33]

Wyoming [143]

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Shrub

More info for the terms: competition, phase

Due to the concentration of salts in
plant tissue, removal of dense stands of black greasewood may help decrease the
alkalinity of some sites, though complete removal of the plant material from the
site is necessary [75].

A combination of triclopyr and
benazolin may be effective in controlling (~80%) black greasewood [53]. Applications of 2,4-D or combined
2,4-D and picloram may also be
effective in controlling black greasewood, especially employing 2 successive
applications [30,119]. Applications of herbicide
are more likely to be effective if administered during the accelerated growth
phase of black greasewood (late May to late June) [119,120]. New shoots are most susceptible
to herbicides [116].

Black greasewood may increase in response to grazing [107]. Removal of
competition can dramatically increase growth rates and total leader length of
black greasewood [120].

Black greasewood is useful in landscaping [78,112].

The leaves, seeds, and stems of black greasewood are edible [50,83].

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More info for the terms: phase, seed

Black greasewood growth starts in early spring [79]. Bud burst generally occurs from late March to early April, though it could occur as early as late February.  After bud burst, there is a period of restricted growth that lasts until mid- to late May, at which point accelerated growth begins. Accelerated growth continues until late June [103,120]. Accelerated growth is most likely related to soil temperatures and moisture, with the end of this phase coinciding with a drop in soil moisture [120].

Black greasewood flowering occurs as early as May and as late as August [15,48,103,134]. Staminate flowers form in mid-May and release pollen in early June. Pistillate flowers are not evident until staminate spikes began to dry (early to mid-July), ensuring cross pollination [103,120]. Seed is set in mid-August [47].

Seed generally matures from September to November [47,134], and seed dispersal occurs from late fall to early winter [47,58]. Maturation may extend over the winter with a few fruits remaining on the plant in early summer of the following year [48]. Black greasewood drops its leaves in fall and early winter [55,79].

More info for the terms: cover, density, prescribed burn, wildfire

Black greasewood sprouts vigorously following burning [115,116,129,150,157], which may result in increased stem density [156]. Following a wildfire in Washington, black greasewood sprouted in the 1st postfire season, and had restored 47% of its preburn cover by April of the 2nd growing season [115]. A study following a Nevada wildfire found that black greasewood sprouts reached approximately 2.5 feet (0.76 m) within 3 years [129]. A low- to moderate-severity prescribed burn study conducted in Oregon found nearly all (90%) black greasewood plants sampled experienced vigorous sprouting 1 year after burning [157].

More info for the terms: adventitious, initial off-site colonizer, secondary colonizer, seed, shrub

POSTFIRE REGENERATION STRATEGY [137]:
Tall shrub, adventitious bud/root crown
Initial off-site colonizer (off-site, initial community)
Secondary colonizer (on-site or off-site seed sources)

More info for the terms: adventitious, dioecious, monoecious, pericarp, presence, root crown, seed, shrubs, stratification

Black greasewood reproduces by seed [48,107] and by sprouting from its root crown and spreading lateral root system [48]. Though some authors assert that black greasewood juveniles more often arise from adventitious buds in roots that have been exposed or mechanically injured than arise from seed [116], a study of a Mono Lake, California, black greasewood population found that the majority of plants were established through sexual reproduction [56].

Breeding system: Some authors report that black greasewood is monoecious [15,16,48,50,96,134], while others describe it as generally monoecious but occasionally dioecious [17,42,74,103,116,120]. On monoecious plants, pistillate flowers are borne in leaf axils below staminate catkin-like spikes [15,16,48,50]. Staminate flowers are borne high on the plant in small, conelike structures at the ends of the smaller branches. Pollen production is generally high [116]. Female flowers are borne singly at the juncture of stem and leaf back from the tip of the small branches  [103]. Black greasewood is cross-pollinated [103,120].

Pollination: Black greasewood is wind pollinated [56,95,116]

Seed production: Seed production is typically low but occasionally abundant [15]. With removal of competing vegetation, seed production may increase dramatically. A Great Basin study documented 20% of black greasewood producing seed in an undisturbed stand, with an average of <20 seeds/plant. In plots where 60% of rabbitbrush and 43% of black greasewood were removed, 43% of remaining black greasewood shrubs produced 250 seeds/plant [120].

Seed dispersal: Winged seeds allow for wind dispersal [47,56,58,116]. In a study at Mono Lake, California, where high windspeeds are common and there are few aboveground barriers, black greasewood seeds were dispersed at least 0.4 mile (700 m) from source plants [58]. It is unclear how far seeds might disperse in vegetated areas with numerous obstacles to trap seed [56].

Seed banking: No information is available on this topic.

Germination: Black greasewood seeds germinate well at cool temperatures and rates of germination are generally high (nearly 100% at 50 oF (10 oC)). Laboratory tests have shown optimum germination temperatures range from 50 to 77 oF (10 to 25 oC) [48]. One hundred percent germination was achieved with a constant temperature of 52 oF (11 oC); 94% germination was achieved with 60 oF (15.5 oC) for 8 hours followed by 52 oF for 16 hours [121]. Seed from Oregon germinated best at 68 oF (20 oC) [48,117]. Seeds from Montana germinated at temperatures ranging from 41 to 104 oF (5-40 oC) [117], though high temperatures (>25 oC) reduced both germination rate and percentage germination, and abnormal seedlings developed [48,117]. Seeds from New Mexico germinated poorly at temperatures above 66 oF (19 oC) [121].

Stratification of seeds is not necessary; laboratory trials have found that black greasewood germinates best at 50 oF without stratification and at 68 to 86 oF (20-30 oC) with stratification. Black greasewood seeds do require a period of afterripening lasting 30-60 days, and a short freeze/thaw cycle may encourage germination due to the breakdown of the pericarp [47].

The bracts of the seeds contain high levels of sodium which, along with other available sodium, is rapidly absorbed by the seedlings [48,49]. Eddleman and Romo [48,49] suggest that accumulating sodium is a means of adjusting the seedling's osmotic potential to cope with saline conditions during establishment. Adjustment of internal osmotic potential enables plants to maintain turgor, growth, and metabolic processes at low water potentials [49]. Germination may be reduced by decreasing osmotic potential, limiting most germination to periods when salts are diluted or leached and conditions are favorable for seedling growth (that is, spring) [118]. Laboratory experiments have demonstrated that black greasewood germinates under moisture stress, and establishment can be successful at low soil moisture levels near the soil surface if moisture at lower levels is sufficient for growth and development. At 0.0 MPa, 0.5% of seeds germinated; germination rates increased with increasing water stress to a maximum of 37.5% at -0.4 MPa. Germination decreased to 26% at -1.6 MPa [22]. Other tests have found that total germination may be high for black greasewood with water potential down to -0.13 MPa; however, the number of days required to reach high germination rates increases [121].

The presence or absence of light has no appreciable impact on germination rates [121].

Seedling establishment/growth: Transplanted black greasewood seedlings reached a mean height of 2.4 feet (0.73 m) and a crown diameter of 2.7 feet (0.83 m) after 12 years [109].

Asexual regeneration: Some authors describe sprouting from the root crown and roots after disturbance [48,78,116]; a study of a greasewood population at Mono Lake, California noted sprouting from wide-ranging lateral roots [56]. However, Harvey and Weaver [72] found no evidence of vegetative reproduction in Montana field experiments (established individuals).

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This species can be found in the following regions of the western United States (according to the Bureau of Land Management classification of Physiographic Regions of the western United States):

BLM PHYSIOGRAPHIC REGIONS [10]:

5 Columbia Plateau

6 Upper Basin and Range

7 Lower Basin and Range

8 Northern Rocky Mountains

9 Middle Rocky Mountains

10 Wyoming Basin

11 Southern Rocky Mountains

12 Colorado Plateau

13 Rocky Mountain Piedmont

14 Great Plains

15 Black Hills Uplift

16 Upper Missouri Basin and Broken Lands

(key to state/province abbreviations)
UNITED STATES AZ CA CO ID MT NE NV NM ND OR SD TX UT WA WY  
CANADA AB SK
MEXICO

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Black greasewood is described as a "stable dominant" under moist-sodic edaphic conditions [47]. A study of saline prairie sites in Canada found black greasewood occurred exclusively on undisturbed sites [19]. However, black greasewood is known to sprout after disturbance [56,115,116,132,150,156,157], making it competitive in early seral communities. With high soil salinity (>1.08%), black greasewood is replaced by species such as saltgrass, iodinebush (Allenrolfea occidentalis), and Utah swampfire (Sarcocornia utahensis) [52].

Sarcobatus vermiculatus var. baileyi (Coville) Jeps. [82]

The currently accepted scientific name of black greasewood is Sarcobatus
vermiculatus (Hook.) Torr. (Chenopodiaceae) [42,43,44,66,74,83,84,85,149].

More info for the terms: seed, stratification

Black greasewood is useful for stabilizing soil on wind-blown areas [54,78,112]. It successfully revegetates processed oil shale [97] and is commonly found on eroded areas and sites too saline for most plant species [76].

Transplanting black greasewood from containers is moderately successful [61,98]; 1 study found 75% survival 5 years after transplanting [61]. Another study found 90% survival through the 1st 6 years after transplanting and >50% survival after 12 years [109]. Some authors report that once transplants are established, they seed well into surrounding areas [98]; others report poor reproduction even with successful transplants [109]. A greenhouse study found cuttings of black greasewood were unable to root [72].

Spring planting the year after seed maturity favors germination, though planting the 2nd fall would also be successful [46,98]. Seeds germinate well at 30 to 60 days following maturation. Long viability is possible; seeds stored in the laboratory for 4 years reached 70% germination in 4 days [48]; with age, seeds increase in ability to germinate at lower temperatures (39 and 50 oF or 4 and 10 oC). Other tests have found that older seed declined in germinability unless it was stratified for 2 to 3 months [46]. In general, stratification of black greasewood seeds does not appear to be necessary, but incubation at 39 oF for 30 to 60 days may improve germination at warmer temperatures [48]. In laboratory experiments, germination was favored by 68 oF (20 oC) on unstratified seed and by 86 oF (30 oC) following stratification. Germination was substantially reduced at 50 oF constant or 68/41 oF (20/5 oC) alternating temperatures [46]. Other lab experiments using a southeastern Montana seed source found total germination was highest (80-97%) between 41 and 77 oF (5-25 oC), though germination was >50% at all temperatures from 41 to 104 oF (5-40 oC). Seedling vigor, however, was poor at warm temperatures (>77 oF, 25 oC) [117]. Additional information on germination can be found in Botanical and Ecological Characteristics.