Hooveria purpurea

(Brandegee) D.W. Taylor & D.J. Keil

Purple Amole

G2Imperiled Found in 3 roadless areas NatureServe Explorer →
G2ImperiledGlobal Rank
Very high - mediumThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.129360
Element CodePMLIL0G050
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
Endemicendemic to a single state or province
KingdomPlantae
PhylumAnthophyta
ClassMonocotyledoneae
OrderAsparagales
FamilyAsparagaceae
GenusHooveria
Synonyms
Chlorogalum purpureumBrandeg.
Concept Reference
Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
Conservation Status
Review Date2011-09-12
Change Date2011-09-12
Edition Date2011-09-14
Edition AuthorsD. Gries, rev. R. Bittman (7/98), rev. M.J. Russo (5/11), rev. A. Tomaino (2011)
Threat ImpactVery high - medium
Range Extent<100 square km (less than about 40 square miles)
Number of Occurrences6 - 20
Rank Reasons
Endemic to California, Chlorogalum purpureum known from approximately 15 extant occurrences. The two occurrences of C. purpureum var. reductum appear to be under greater threat than those of C. purpureum var. purpureum. Threats include cattle grazing on the Los Padres National Forest, illegal trespass by motorcycles, displacement by non-native annual grasses, and wildfire.
Range Extent Comments
From USFWS (2008): Chlorogalum purpureum var. purpureum is endemic to the Santa Lucia Range of Monterey and San Luis Obispo counties, California, and is known from two properties: several localities on Fort Hunter Liggett, southern Monterey County; and one locality on Camp Roberts in northern San Luis Obispo County. A distance of approximately 31 km (19 miles) separates the locality on Camp Roberts from the nearest locality on Fort Hunter Liggett (Holland 2004). Chlorogalum purpureum var. reductum is endemic to the La Panza Range in central San Luis Obispo County. The taxon is known only from a small geographic area. The main population is approximately 0.8 km (0.5 mile) east of the southern end of Camatta Canyon. It occurs approximately 61 km (38 miles) southeast of the population of C. purpureum var. purpureum on Camp Roberts and 92 km (57 miles) southeast of the nearest site on Fort Hunter Liggett. One site for C. purpureum var. reductum is at the intersection of State Highway 58 and Red Hill Road which comprises 3 ha (7.5 ac) of land south of the highway and probably less north of the highway. Most of this site is in the Los Padres National Forest; the site continues on either side of State Highway 58 within a right-of-way of the California Department of Transportation, and then northward and also likely southward onto private lands. The second site is approximately 6.5 km (4 miles) south of the first and comprises approximately 0.1 ha (0.25 ac) of private land.
Occurrences Comments
C. purpureum var. purpureum is known from 13 occurrences in Monterey County (Fort Hunter Liggett Military Reservation) and 1 occurrence San Luis Obispo County (Camp Roberts Military Reservation); C. purpureum var. reductum is known from 2 occurrences in San Luis Obispo County (EO data in the NatureServe central database as of July 2011).
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Threat Impact Comments
Chlorogalum purpureum var. reductum is threatened by cattle grazing, illegal trespass by motorcycles, displacement by non-native annual grasses, and wildfire (USFWS 2008). Chlorogalum purpureum var. purpureum is also threatened by non-native annual grasses, and wildfire; however, grazing and military activites are not currently impacting Chlorogalum purpureum var. purpureum (USFWS 2008). Other threats include habitat fragmentation, habitat conversion, foot traffic, and road maintenance(CNPS 2011).

From USFWS (2008): Non-native annual grasses and other invasive plant species continue to be a threat to both taxa. Invasive plant species may displace the Chlorogalum purpureum by outcompeting and monopolizing limited resources (growing space, sunlight, soil nutrients, water), with the potential effects of preventing growth and recruitment, and may also alter characteristics of the fire regime, such as frequency, intensity, and seasonality of fires. Because of the clumped and limited distribution of the plants in a semiarid environment, a wildfire could destroy a substantial portion of the population. The frequency of fires in California is increasing (Syphard et al. 2007), and fires at certain times of the year have the ability to prevent annual reproductive success of Chlorogalum purpureum plants which are susceptible to damage by fire when the living structures, including the seeds, are above ground or near the soil surface. However, fires at certain times of the year may potentially benefit the plants by removing other competitive plants.
Ecology & Habitat

Description

From FWS (2008): Chlorogalum purpureum is a perennial lily with a basal cluster of bright green leaves, which are elongate, with a wavy margin, and with a thickened midrib (USFWS 2002, Holland 2004, Guretzky et al. 2005). The basal leaves typically range from 1 to 8 in number (Woodbury 2005b), but as many as 14 have been recorded (Guretzky et al. 2005), with a width of 2 to 5 mm (0.1 to 0.2 inch). The bulb is ovoid, 2.5 to 3.0 cm (0.98 to 1.2 inches) long, white to brown in color, and occurs in the upper few inches of soil (USFWS 2002, Holland 2004). The flower cluster is borne on a single stem with multiple branches. The flowers are deep blue or purple with bright yellow anthers. The fruits are capsules, each with three chambers containing one or two black, ovoid seeds.

Chlorogalum purpureum var. reductum seems to be identical to Chlorogalum purpureum var. purpureum except for its compact, dwarf habit of growth. The two are generally distinct in their extreme forms, but may intergrade (Flora of North America Editorial Committee 2002a).

Diagnostic Characteristics

Narrow, wavy 1-8(14) bright green basal leaves with thick midribs. There are usually one to eight leaves. Widely spaced blue or purple flowers on naked stem with long stamens with yellow anthers around a protruding style.

Habitat

Cismontane woodland, valley and foothill grassland, and chaparral, between 205 and 630 m elevation (CNPS 2011). Both varieties have been reported to grow in association with cryptogamic crusts (USFWS 2008). All locations for C. purpureum var. purpureum and C. purpureum var. reductum are in semiarid environments and have a Mediterranean climate with summers that are hot and dry, and winters that are cool and wet (USFWS 2008).

From USFWS (2008): On Fort Hunter Liggett, there are hundreds of discontinuous patches of C. purpureum var. purpureum in grassland, oak savanna, and oak woodland communities where other vegetation is sparse. They occur in association with both deep and relatively thin soils. Most of the soils are loamy, underlain by clay, and with fine gravel generally less than 0.5 cm (0.2 inch) in diameter on the surface. Most sites have flat topography or slopes of less than 10%. A few populations occur along ridgetop terraces (USFWS 2008). C. purpureum var. reductum in the Los Padres National Forest grows in open areas on a ridgetop in blue oak savanna and annual grassland, and in open areas in grassland and woodland. Most reports state that C. purpureum var. reductum grows in serpentine soil. However, the USFWS (2002) reports it to grow in "well-drained red clay soils" with a large amount of gravel and pebbles. The soil has also been described as a supermature lateritic (not serpentine as in Munz or Miocene redbeds of others) with very little nutrient value, hard and red when dry. In sum, the soil type for C. purpureum var. reductum is not serpentine.
Terrestrial Habitats
Forest/WoodlandWoodland - HardwoodWoodland - MixedShrubland/chaparralGrassland/herbaceousBarrens
Other Nations (1)
United StatesN2
ProvinceRankNative
CaliforniaSNRYes
Threat Assessments
ThreatScopeSeverityTiming
2 - Agriculture & aquacultureRestricted (11-30%)Serious or 31-70% pop. declineHigh (continuing)
2.3 - Livestock farming & ranchingRestricted (11-30%)Serious or 31-70% pop. declineHigh (continuing)
4 - Transportation & service corridorsLarge - restrictedModerate or 11-30% pop. declineHigh (continuing)
4.1 - Roads & railroadsLarge - restrictedModerate or 11-30% pop. declineHigh (continuing)
6 - Human intrusions & disturbanceLarge - restrictedModerate or 11-30% pop. declineHigh (continuing)
6.1 - Recreational activitiesLarge - restrictedModerate or 11-30% pop. declineHigh (continuing)
6.2 - War, civil unrest & military exercisesLarge - restrictedModerate or 11-30% pop. declineInsignificant/negligible or past
7 - Natural system modificationsLarge (31-70%)Moderate or 11-30% pop. declineHigh (continuing)
7.1 - Fire & fire suppressionLarge (31-70%)Moderate or 11-30% pop. declineHigh (continuing)
8 - Invasive & other problematic species, genes & diseasesLarge (31-70%)Moderate or 11-30% pop. declineHigh (continuing)
8.1 - Invasive non-native/alien species/diseasesLarge (31-70%)Moderate or 11-30% pop. declineHigh (continuing)

Plant Characteristics
Economic Value (Genus)No
Roadless Areas (3)
California (3)
AreaForestAcres
Black MountainLos Padres National Forest16,818
Garcia MountainLos Padres National Forest7,850
Machesna MountainLos Padres National Forest12,271
References (16)
  1. Bittman, R. 1998. Lead Botanist, California Natural Diversity Database. Unpublished notes on fifty rare plants of California for purposes of updating Element Global Ranking (EGR) forms. California Natural Heritage Division, Dep. of Fish &amp; Game, Sacramento, California, U.S.A.
  2. California Department of Fish and Game. 2000. Natural Diversity Database (RareFind 2), Version 2.1.2, January 25, 2000. Downloaded in 2003.
  3. California Native Plant Society (CNPS). 2001. Inventory of Rare and Endangered Plants of California (sixth edition). Rare Plant Scientific Advisory Committee, David P. Tibor, Convening Editor. California Native Plant Society. Sacramento, CA. x + 388pp.
  4. California Native Plant Society (CNPS). 2011. Inventory of Rare and Endangered Plants. California Native Plant Society. Sacramento, CA. Online. Available: http://www.cnps.org/inventory (accessed 2011).
  5. California Natural Diversity Database (CNDDB). 2025. RareFind Version 5.3.0. California Department of Fish and Game, Sacramento.
  6. Flora of North America Editorial Committee (FNA). 2002a. Flora of North America north of Mexico. Vol. 26. Magnoliophyta: Liliidae: Liliales and Orchidales. Oxford Univ. Press, New York. xxvi + 723 pp.
  7. Guretzky, J.A., E.R. Clark, and D. Woodbury. 2005. Life history traits of the threatened purple amole (<i>Chlorogalum purpureum </i>var. <i>purpureum</i>). Prepared for Fort Hunter Liggett by the Construction Engineering Research Laboratory, U.S. Army Corps of Engineers, Champaign, IL.
  8. Holland, R.F. 2004. Current knowledge and conservation status of <i>Chlorogalum purpureum </i>Brandegee var. <i>purpureum</i>, the purple amole, in California. Prepared for the California Army National Guard, Camp Roberts. Auburn, CA.
  9. Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
  10. NatureServe. 2025. NatureServe Network Biodiversity Location Data. NatureServe, Arlington, Virginia.
  11. <p>NatureServe's Rapid Analysis of Rarity and Endangerment Conservation Assessment Tool (RARECAT). 2025. Version: 2.1.1 (released April 04, 2025).</p>
  12. Skinner, M.W., and B.M. Pavlik, eds. 1997 (1994). Inventory of rare and endangered vascular plants of California. 1997 Electronic Inventory Update of 1994 5th edition, California Native Plant Society, Special Publication No. 1, Sacramento.
  13. Taylor, D.W. and D.J. Keil. 2018. <i>Hooveria</i>, a new genus liberated from <i>Chlorogalum </i>(Agavaceae subf. Chlorogaloideae). Phytoneuron 67: 1-6.
  14. U.S. Fish and Wildlife Service (USFWS). 1995. Category and Listing Priority Form.
  15. U.S. Fish and Wildlife Service (USFWS). 2002. Endangered and threatened wildlife and plants; final designation of critical habitat for <i>Chlorogalum purpureum</i>, a plant from the south coast ranges of California. Federal Register 67(206):65414-65445.
  16. U.S. Fish and Wildlife Service (USFWS). 2008. Purple Amole (<i>Chlorogalum purpureum</i>) Five-year Review: Summary and Evaluation. U.S. Fish and Wildlife Service, Ventura, CA. 33 pp. [http://ecos.fws.gov/docs/five_year_review/doc1996.pdf]