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DRAFT March 2012 PLANTS White-Margined Beardtongue (Penstemon albomarginatus) White-Margined Beardtongue (Penstemon albomarginatus) Legal Status State: S11 Photo courtesy of Makela Mangrich. California Rare Plant Rank: 1B.12 Federal: Bureau of Land Management Sensitive Critical Habitat: N/A Recovery Planning: N/A Taxonomy White-margined beardtongue (Penstemon albomarginatus) is a member of the plantain family (Plantaginaceae), formerly included in the figwort family (Scrophulariaceae) (Jepson Flora Project 2011). M.E. Jones first described the species in 1908 (as cited in Anderson 1999). The taxonomic status of white-margined beardtongue is unique and it has never been confused with any other species of Penstemon (Anderson 1999), nor is it believed to hybridize with other species in the genus (Etyemezian et al. 2010). This perennial herb is 15 to 35 centimeters (5.9 to 13.8 inches) tall (CNPS 2011; Jepson Flora Project 2011). Descriptions of the species’ physical characteristics can be found on the Jepson eFlora (Jepson Flora Project 2011), and in MacKay (2006) and Anderson (1999). Distribution General White-margined beardtongue is known from only four general locations: two in the Mojave Desert of Southern Nevada, one in the 1 2 S1: Critically imperiled. 1B: Rare, threatened, or endangered in California and elsewhere. X.1: seriously threatened in California. 1 Species Accounts March 2012 DRAFT March 2012 PLANTS White-Margined Beardtongue (Penstemon albomarginatus) Mojave Desert of southeast California, and one in the Sonoran Desert of northwest Arizona (Smith 2001, cited in Etyemezian et al. 2010). Its distribution in California is restricted to eastern San Bernardino County (CDFG 2012a), within the following quadrangles (listed from west to east): Troy Lake, Hector, Lavic Lake, Sleeping Beauty, Ludlow, and Cadiz Summit. The majority of the 23 occurrences documented in the California Natural Diversity Database (CNDDB), all of which are within the Plan Area (CDFG 2012a), are located north of Interstate 40, including a large population occurring in a 4-mile-long wash northeast of Pisgah Crater, extending southwest from Sleeping Beauty Peak, and terminating in a flat spreading basin south of the freeway (CDFG 2012a; MacKay 2006). The species is also found in another wash extending south–southeast from Sleeping Beauty Peak, and in a number of smaller locations mapped since 2008 west of there in the vicinity of Hector (CDFG 2012a). South of Interstate 40, the species has been documented in the vicinity of Lavic Lake and Swede Hill (southeast of Lavic Lake) (CDFG 2012a). Figure SP-P35 shows the range of white-margined beardtongue in California. Distribution and Occurrences within the Plan Area Historical Five CNDDB occurrences were originally recorded prior to 1990, although they are all presumed extant (CDFG 2012a). The three oldest records, from 1935 to 1940, are located (1) in the vicinity of Lavic Lake; (2) south of Swede Hill, east of Lavic Lake; and (3) near the western junction of Interstate 40 and Highway 66 in the Ludlow quadrangle. These three records have not been updated since then. The two remaining records, last updated in 1989, are located (1) in the Cadiz Summit quadrangle in the vicinity of Highway 66, and (2) in a wash extending south and southeast of Sleeping Beauty Peak on land managed by the Bureau of Land Management (BLM). The Cadiz Summit occurrence was added by the California Department of Fish and Game as a “best guess” based on a 1941 collection that documented whitemargined beardtongue plants “between Cadiz and Danby.” The site was searched by Scogin in 1989 and later by J. Andre, but neither botanist 2 Species Accounts March 2012 DRAFT March 2012 PLANTS White-Margined Beardtongue (Penstemon albomarginatus) observed white-margined beardtongue in this location. Scogin noted that there is “too much gravel cover, sand is too shallow” (CDFG 2012a). This occurrence needs additional field work. Recent Eighteen CNDDB occurrences have been observed since 1990, 16 of which are documented on BLM land (CDFG 2012a). Ownership of the land for the two remaining records observed since 1990 is unknown. All 18 of these records are located east of the Newberry Springs area at the western edge of the known range of the species in California and are presumed extant. Figure SP-P35 provides an overview of the species model for whitemargined beardtongue, with these occurrences overlaid (CDFG 2012a). Natural History Habitat Requirements The CNDDB element occurrence information cites the habitat requirements of white-margined beardtongue as Mojave Desert scrub and desert dunes, specifically in deep, stabilized desert sand, and in washes and along roadsides (CDFG 2012a). Within California, Andre (2010) notes that this species occurs on mostly “fine alluvial sands within a sparse creosote bush scrub community.” White-margined beardtongue occurs from 635 to 1,065 meters (2,083 to 3,494 feet) (CDFG 2012a). There are additional records in the Consortium of California Herbaria that, if verified, would extend this elevation range to as low as 426 meters (1,398 feet) (Jepson Flora Project 2011). Etyemezian et al. (2010) studied white-margined beardtongue habitat requirements in the Nevada populations over the course of 2 years, with particular emphasis on the effects of eolian, fluvial, and dust deposition processes on white-margined beardtongue populations. Some of their findings include: All of the study sites where white-margined beardtongue was present were characterized as sandy (>80% sand, >85% at 3 Species Accounts March 2012 DRAFT March 2012 PLANTS White-Margined Beardtongue (Penstemon albomarginatus) surface) to a depth of at least 60 centimeters (24 inches), having slopes in the range of 1.8%–4.6% with aspects (facing direction) in the range of 174–309 degrees from north; Sandy soils with shrub covers of less than 20% and an accumulation of surface carbonates in the canopy inter‐spaces appear to provide the best habitats for healthy white-margined beardtongue populations; The Bluepoint and Arizo soil series supported the healthiest populations in both Clark and Nye Counties (Nevada), and wherever these soils occur, the possibility of discovering new white-margined beardtongue populations exists; and Results of a cluster analysis of the study sites indicated that for Clark County, the native perennial grass, big galleta (Hilaria [Pleuraphis] rigida), and the native shrubs, winter fat (Krascheninnikovia lanata) and Shockley’s goldenhead (Acamptopappus shockleyi), are the most likely indicator species for the presence of white-margined beardtongue. White bur-sage (Ambrosia dumosa), creosote bush (Larrea tridentata), and Pima rhatany (Krameria erecta) are relatively ubiquitous and apparently unrelated to the presence of white-margined beardtongue (Etyemezian et al. 2010). Table 1. Habitat Associations for White-Margined Beardtongue Land Cover Habitat Type Designation Mojave Desert Primary habitat scrub, desert dunes Habitat Parameters 1,398 to 3,494 feet elevation Supporting Information Jepson Flora Project 2011; CDFG 2012a; Etyemezian et al. 2010 Reproduction As a short-lived perennial with a large, deep root system, white-margined beardtongue appears to reproduce primarily through production and dispersal of seed (Etyemezian et al. 2010). Flowers emerge between March and May (Jepson Flora Project 2011); peak flowering appears to occur in April of most years (Etyemezian et al. 2010). 4 Species Accounts March 2012 DRAFT March 2012 PLANTS White-Margined Beardtongue (Penstemon albomarginatus) Like many Mojave Desert perennial plants, white-margined beardtongue reproductive events are rare and episodic and may require a combination of successive wet years that favor seed production, seed germination, and seedling growth (Etyemezian et al. 2010). Andre (2010) notes that this species maintains a substantial soil seed bank and survives underground as a subterranean heterotrophy (root/caudex) during dry years (Andre 2010). Even during average years of precipitation, a large percentage of the seed bank will not germinate and many living plants remain dormant underground. Only a subset of plants will put on above-ground growth, and an even fewer number flower and set seed. Seed banks can persist in the soil for many decades before germinating (Andre 2010). Andre (2010) also has observed and documented frequent localized extinctions of cohorts with rapid establishment of plants in previously unoccupied areas. He concludes that plants at the California occurrence behave like biennials or short-lived perennials, relying upon the maintenance of a viable seed bank, and over time exhibit a shifting distribution within the eolian sands where they occur (Andre 2010). Etyemezian et al. (2010) observed very limited seed production and dispersal of white-margined beardtongue at study sites in Nevada during the drought years of 2008–2009. They attributed the lack of reproductive success to drought and insect herbivory at two sites, but did observe seed dispersal at one site in 2009. Seed dispersal distances ranged from 1 to 15 centimeters (0.4 to 6 inches) at this site. MacKay (2006) noted that white-margined beardtongue is present in some washes but absent in other drainages nearby, and suggests that might be due to both limited seed dispersal distances and the lack of suitable stabilized deep sand in those other drainages (MacKay 2006). She suggests that the small seeds could be scattered short distances by ants or rodents, or may get transported by water in very wet years. The tendency for plants to occur in scattered groups of up to 20 individuals, and the fact that young cuttings produce adventitious roots in experiments (Scogin 1989, as cited in MacKay 2006), suggest that vegetative reproduction may occur in this species in its natural habitat, even though attempts to propagate from cuttings at the garden failed (Scogin 1989, as cited in MacKay 2006). 5 Species Accounts March 2012 DRAFT March 2012 PLANTS White-Margined Beardtongue (Penstemon albomarginatus) Ecological Relationships The success of white-margined beardtongue is dependent upon a variety of interactions with pollinators and other nearby plant species, as well as a variety of ecological processes. The showy flowers are visited by several insects, including small carabid beetles, large flies, and vespid wasps with orange abdomens. Pollen was observed on upper-body surfaces of the vespids, making them the most likely pollinator of white-margined beardtongue (Scogin 1989, as cited in MacKay 2006). White-margined beardtongue establishment is much more likely in canopy inter‐spaces than under plant canopies, but Etyemezian et al. (2010) could not determine whether competition with other perennial species or other micro‐environmental factors were responsible for this phenomenon (Etyemezian et al. 2010). For the few individuals they noticed growing in under canopy locations, the overstory species was equally likely to be white bur-sage or big galleta grass (only in Clark County), but never creosote bush. Etyemezian et al. (2010) studied eolian processes of sediment transport within white-margined beardtongue habitat areas. They conclude that it is unlikely that present‐day eolian sand transport processes have any appreciable effect on habitat areas because the eolian deposits in the sites were formed over geological time scales and study measurements of sand transport indicated that present‐day rates for eolian sediment transport are very slow to create new deposits. However, they conclude that fluvial processes and sediment transport via dry wash channels is the dominant present-day geomorphic process at white-margined beardtongue sites in Nevada (Etyemezian et al. 2010) Population Status and Trends Global: G2, Imperiled (CDFG 2012b) State: S1, Critically Imperiled (CDFG 2012b) White-margined beardtongue is classified as a 1B.1 rare plant species by the California Rare Plant Ranking system. Species with the 1B rank 6 Species Accounts March 2012 DRAFT March 2012 PLANTS White-Margined Beardtongue (Penstemon albomarginatus) are rare, threatened, or endangered in California and elsewhere. The 0.1 threat rank indicates that this species is seriously threatened (over 80% of occurrences are threatened or have a high degree and immediacy of threat) in California. Abundance estimates of white-margined beardtongue are heavily dependent upon rainfall factors, and are difficult to assess due to the large number of individuals that survive underground during dry years (Andre 2010). One of the largest occurrences of white-margined beardtongue in California is a large, X-shaped occurrence that runs approximately 4 miles along a wash and 2 miles along a spreading basin. In 1989, 450 plants seen were seen at this site, which was damaged by military activities that same year. In 2008, botanists observed 42 colonies of white-margined beardtongue at this location (CDFG 2012a). Eight plants were observed at the occurrence south of the Sleeping Beauty lava flows in 1989. There are no population estimates for the occurrences from 1935 to 1940. More recent occurrences (2008– 2010) generally do not provide population estimates to the CNDDB (CDFG 2012a). Where population numbers are provided, they are typically from 1 to 17 individuals (CDFG 2012a). In Nevada, Etyemezian et al. (2010) re-surveyed 12 white-margined beardtongue populations in 2008–2009 that were documented during 1997–1998 by F.J. Smith. These surveys resulted in population estimates of 125,825 plants in Clark County and 78,954 plants in Nye County. These estimates are almost five times greater than the earlier estimates of 25,964 for Clark County and two times greater than the 42,200 plants estimated for Nye County, both during 1997–1998. Surveys in 2008–2009 also were conducted in years of below-average rainfall, so the actual size of white-margined beardtongue in Nevada could be even greater than these estimates (Etyemezian et al. 2010). Threats and Environmental Stressors All of the white-margined beardtongue occurrences in California are located within or adjacent to BLM verified solar and wind project applications, the BLM Pisgah Solar Energy Zone, or approved solar projects. In addition, they are located near possible military base 7 Species Accounts March 2012 DRAFT March 2012 PLANTS White-Margined Beardtongue (Penstemon albomarginatus) expansion lands, including Fort Irwin Army Base and Twentynine Palms Marine Corps Air Ground Combat Center. According to the Land Acquisition/Airspace Establishment Study Draft Environmental Impact Statement (EIS), white-margined beardtongue is located in the Lavic Lake Training Area, but it was not observed or discussed as potentially occurring in the expansion areas to the west, south, and east of the existing combat center (Department of the Navy 2011). However, the EIS also reports potential habitat (i.e., creosote bush scrub and/or desert dunes) for white-margined beardtongue in all three expansion areas, so there is likely some risk to this species that would result from these expansion plans. This species is also potentially threatened by the presence of Interstate 40 and numerous utility access roads that facilitate movement of people and off-highway vehicles to the occupied habitat areas. MacKay (2006) notes that repeated destruction of aboveground plants may use up nutrient stores within the long taproot of the plant and result in declines of this species. Large, organized offroad races also create massive dust clouds and are held in areas adjacent to white-margined beardtongue habitat areas in Nevada. The dust has been seen rising hundreds of feet into the air (Mangrich, pers. obs. 2009), and poses a potential threat to the Nevada population’s pollinators, as well as the plant’s photosynthetic capacity (Mangrich, pers. obs. 2009). Although there are no known organized off-road races held near occupied habitat within the Plan Area, offhighway vehicle activity in the Plan Area could pose similar, albeit somewhat less severe, threats. Other threats include the presence of power lines and pipelines that bring human disturbance into areas of occupied habitat (MacKay 2006). Military activities (e.g., camping) have also been observed in the vicinity of occupied habitat areas, which could increase trampling damage to the species (MacKay 2006). Although white-margined beardtongue is a showy plant, it does not appear that there is a threat resulting from horticultural efforts because it doesn’t propagate well from cuttings, and transplantation efforts have been unsuccessful (Scogin 1989, as cited in MacKay 2006). 8 Species Accounts March 2012 DRAFT March 2012 PLANTS White-Margined Beardtongue (Penstemon albomarginatus) Conservation and Management Activities All of the California occurrences of white-margined beardtongue are within the West Mojave Plan area (MacKay 2006), and as such, would be subject to conservation and management activities associated with that plan. These activities include the establishment of a habitat conservation area, although it is unknown if that area encompasses known occurrences of white-margined beardtongue, and plant conservation strategies and an acquisition program to acquire and enhance the protection of private lands within the habitat conservation area (BLM 2005). The BLM manages for sensitive plant species occurring on land it administers, including on lands where white-margined beardtongue have been documented. Management priorities are consistent with the BLM’s principles of multiple use and include, but are not limited to: developing and implementing range-wide and/or site-specific management plans for sensitive plant species that include specific habitat and population management objectives designed for recovery; ensuring that BLM activities affecting the habitat of sensitive plant species are carried out in a manner consistent with the objectives for managing those species; and monitoring populations and habitats of candidate plant species to determine whether management objectives are being met (BLM 2003). Data Characterization White-margined beardtongue habitat requirements and general reproductive observations (including seed-setting events, seed predation, and plant recruitment; longevity; and mortality in relation to precipitation) have been documented recently, most notably by Etyemezian et al. (2010). However, this study focused on populations in Nevada, not California. In addition, these studies were conducted over 2 years; the study authors suggest longer-term monitoring of these populations. They also recommend that a genetic analysis of existing populations be conducted to better understand the impact of the reproductive isolation of the Nevada, California, and Arizona populations and to assess the overall genetic diversity within the species (Etyemezian et al. 2010). 9 Species Accounts March 2012 DRAFT March 2012 PLANTS White-Margined Beardtongue (Penstemon albomarginatus) There are still data gaps in overall population trends due to a poor understanding of the species’ seed dispersal and recruitment and pollination. Researchers have speculated about pollinator relationships (MacKay 2006), but no peer-reviewed literature on the subject has been published. In addition, no studies have examined seed viability, longevity in the soil, or how long plants can survive dormancy. In addition, the requirements for seed germination and establishment of new plants in the California population are unknown (Etyemezian et al. 2010). MacKay (2006) also notes the need for additional propagation studies to determine if seedlings, cuttings, or transplanted plants could be used for mitigation efforts. Management and Monitoring Considerations Species protection activities should focus on CNDDB occurrences known to occur in eastern San Bernardino County (CDFG 2012a), as well as modeled habitat. The long-term viability of populations may also rely on the protection of habitat corridors between these populations. Because so little is known about the abundance and distribution of white-margined beardtongue in California, and because of their ability to survive underground for long periods of time, focused surveys for this species should be conducted within appropriate habitat in high-rainfall years in the Plan Area. Due to the large, deep root system of white-margined beardtongue, transplanting individuals from threatened populations to suitable sites will not likely be a practical mitigation tool. Possibly, seed can be used to establish new populations at sites that would be suitable (Etyemezian et al. 2010). Predicted Species Distribution in Plan Area There are 426,989 acres of modeled suitable habitat for whitemargined beardtongue in the Plan Area. Modeled suitable habitat occurs in the Bullion Mountains-Bristol Lake ecoregion subsection from 1,300 to 3,500 feet in elevation. Modeled suitable habitat includes scrub and wash vegetation communities, as well as desert dunes and sand flats and desert playas. Appendix C includes specific model parameters and a figure showing the modeled suitable habitat in the Plan Area. 10 Species Accounts March 2012 DRAFT March 2012 PLANTS White-Margined Beardtongue (Penstemon albomarginatus) Literature Cited Anderson, J.L. 1999. “The White-Margined Penstemon (Penstemon albomarginatus Jones), a Rare Mohave Desert Species, and the Hualapai Mountains Land Exchange in Mohave County, Arizona.” Phoenix, Arizona: U.S. Bureau of Land Management. Accessed November 20, 2011. http://www.fs.fed.us/rm/pubs/ rmrs_p023/rmrs_p023_027_037.pdf. Andre, J. 2010. “Rebuttal Testimony in the Matter of Docket No. 08AFC-13 the Application for Certification for the Calico Solar Project. Submitted to the State of California Energy Resources Conservation and Development Commission.” July 29, 2010. BLM (Bureau of Land Management). 2003. “Special Status Plant Management.” BLM Manual Supplement 6840.06. Last revised January 3, 2003. Accessed November 21, 2011. http://www.blm.gov/pgdata/etc/medialib//blm/ca/pdf/ pdfs/pa_pdfs/biology_pdfs.Par.428edb73.File.pdf/ 6840.06-supplement.pdf. BLM. 2005. “Chapter Five Statutory Sections.” Final Environmental Impact Report and Statement for the West Mojave Plan: A Habitat Conservation Plan and California Desert Conservation Area Plan Amendment Vol 1. Accessed December 22, 2011. http://www.blm.gov/ca/pdfs/cdd_pdfs/wemo_pdfs/plan/we mo/Vol-1-Chapter1_Bookmarks.pdf. CDFG (California Department of Fish and Game). 2012a. “Penstemon albomarginatus.” Element Occurrence Query. California Natural Diversity Database (CNDDB). RareFind, Version 4.0 (Commercial Subscription). Sacramento, California: CDFG, Biogeographic Data Branch. Accessed February 2012. http://www.dfg.ca.gov/biogeodata/cnddb/ mapsanddata.asp. CDFG. 2012b. Special Vascular Plants, Bryophytes, and Lichens List. California Natural Diversity Database (CNDDB). January 2012. Accessed March 2012. http://www.dfg.ca.gov/biogeodata/ cnddb/plants_and_animals.asp. 11 Species Accounts March 2012 DRAFT March 2012 PLANTS White-Margined Beardtongue (Penstemon albomarginatus) CNPS (California Native Plant Society). 2011. “Penstemon albomarginatus.” Inventory of Rare and Endangered Plants, Online ed. Version 8-01a. Sacramento, California: CNPS. Accessed November 21, 2011. http://www.cnps.org/inventory. Department of the Navy. 2011. Draft Environmental Impact Statement Land Acquisition and Airspace Establishment to Support LargeScale Marine Air Ground Task Force Live Fire and Maneuver Training. Marine Corps Air Ground Combat Center Twentynine Palms, California. February 2011. Etyemezian, V., J. King, S. Zitzer, G. Nikolich, J. Gillies, and J. Mason. 2010. Sediment Transport to White‐Margined Penstemon Habitat (Penstemon albomarginatus). 2005‐NSHE‐502A‐P. Prepared for Department of Air Quality and Environmental Management Desert Conservation Program, Clark County, Nevada. March 29, 2010. Jepson Flora Project. 2011. “Penstemon albomarginatus.” M. Wetherwax and N.H. Holmgren. Jepson eFlora [v. 1.0]. Berkeley, California: University of California. Accessed December 8, 2011. Accessed November 20, 2011. http://ucjeps.berkeley.edu/interchange/I_treat_indexes.html. MacKay, P.J. 2006. “White-Margined Beardtongue.” West Mojave Plan Species Accounts. U.S. Department of the Interior, Bureau of Land Management. January 2006. Accessed November 2011. http://www.blm.gov/ca/pdfs/cdd_pdfs/whitemarg1.PDF. Mangrich, M. 2009. Personal observation of an off-road vehicle race near Primm, Nevada, in April 2009 in areas where whitemargined beardtongue was documented the day before. 12 Species Accounts March 2012