The Rare, Threatened, and Endangered Plants of California
Glossary of Terms and Field Descriptions
(Adopted and modified from the CNPS Inventory, 6th Edition, 2001)
The heart of the CNPS Inventory is our assessment of the current conservation status of each of our state's rare, threatened, and endangered plants. We present these assessments together with a summary of current information on the distribution and ecology of each taxon. We also include entries for plants that were considered but rejected for one or more reasons, as well as other scientific names that have been used in the standard literature or in previous editions of this Inventory.
Basis for Inclusion
The vast majority of the taxa in this Inventory are vascular plants (ferns, fern allies, gymnosperms, and flowering plants). We also present our evaluation of rarity and endangerment of California's bryophytes (mosses, liverworts, and hornworts). Algae, fungi, and lichens are not treated here.
A plant must be native to California to be included. Ornamentals, plants escaped from cultivation, and naturalized plants are excluded. So are the sporadic hybrids that sometimes occur under natural conditions. The relatively trivial color variants and occasional departures from typical vegetative or floral conditions, referred to by botanists as "forma," are similarly excluded.
This Inventory focuses on plants that are rare in California. A very small number of plants that are still somewhat common in California are included because they are in decline and face further immediate threats. We recognize that extensive habitat alteration and pervasive human impacts pose serious threats to many other species that are still common. However, evaluation of threats to species that are neither rare nor imminently becoming so is outside the scope of this Inventory. By limiting our scope in this way, we in no way imply that these species are not of concern.
The plants in this Inventory are presented by their scientific names which have been properly published according to the International Code of Botanical Nomenclature. See Shevock (1993) for a general discussion of nomenclature.
In its simplest form, a scientific name has three parts. The first is the genus name. It is always capitalized. The second part is the specific epithet, often incorrectly called "the species name." Together, these two components make up the species name. If a scientific name is presented in its most complete form, these two words will be followed by the names of one or more persons, often in an abbreviated form, who first published the specific epithet or subsequently published a taxonomic modification of the plant. These names are the authorities. If a portion of an authority occurs within parentheses, then the author in parentheses originally placed the epithet in a different genus or species, or once assigned it to a different taxonomic rank. The name cited outside the parentheses is that of the person who published the combination as it now appears.
Often the scientific name is more complex because botanists have recognized categories below the level of species. The two most useful are the subspecies (abbreviated ssp.) and the variety (abbreviated var.) These names are also displayed according the International Code and they have their own authorities.
Consider the example Penstemon newberryi Gray var. sonomensis (Greene) Jeps. Penstemon is the genus name; newberryi is the specific epithet; Gray, for Asa Gray, is the author of the specific epithet; var. is the abbreviation for variety; sonomensis is the subspecific epithet; (Greene), for Edward L. Greene, first described the var. sonomensis as a full species; and Jeps., for Willis Lynn Jepson, modified its taxonomic position and made it a variety of P. newberryi. Following the general practice for foreign words and phrases, Latin portions of the name (genus, species, and infraspecific epithet) are typically distinguished from surrounding text with underlining or italic typeface.
We use what we consider to be the current, best nomenclature based on the recommendations of the Rare Plant Program Committee and consultation with taxonomic authorities. Many names in this Inventory have been in use for a long time, appearing in Munz (1959, 1968, 1974) and Abrams (1923-1960). Others have been introduced or reintroduced to us in The Jepson Manual (1993) and The Jepson Online Interchange, or described new to science in the last several years.
The usage in this Inventory does not follow any single published source, though if other considerations are equal, we use the names found in The Jepson Manual and/or on their Online Interchange. When the nomenclature we use varies from that of The Jepson Manual, we include information in the Notes section of each entry describing the situation. See Skinner and Ertter (1993) for a discussion of taxonomic coordination between the Inventory and The Jepson Manual.
Where there is disagreement among experts on taxonomic distinctiveness, we lean towards recognizing doubtfully distinct taxa. Such taxa are typically assigned to List 3. By encouraging protection until taxonomic questions are resolved, we hope to reduce ex post facto regret over taxa that have been shown to be distinct only after their disappearance.
We do not include taxa that lack formally published scientific names.
Each of the plants has a common or vernacular name. Although the majority of the plants in the Inventory have no real common name, we include them because it is often easier for many of us to refer to a plant by a more familiar sounding name. Most of the common names were coined by Leroy Abrams for his Illustrated Flora of the Pacific States. In other instances, we simply follow his lead by contriving names, usually by translating the Latin or Greek roots into English or by selecting an appropriate geographical reference or person's name. We attempt to follow Kartesz and Thieret (1991) in matters of capitalization, spelling, and hyphenation of common names.
Each entry includes the technical name of the family to which the plant belongs. Note that all of these names end with the suffix "-aceae." A few plant families have older, alternative names that the International Code allows to be used because their widespread acceptance predates formal nomenclature. Gramineae is a perfectly acceptable alternative for Poaceae; Compositae for Asteraceae; Cruciferae for Brassicaceae; Umbelliferae for Apiaceae; Leguminosae for Fabaceae; and Labiatae for Lamiaceae. However, these old names are gradually losing favor, so we use the standardized, modern names for these families.
California Rare Plant Ranks (formerly known as CNPS Lists)
In the spring of 2011, CNPS officially changed the name “CNPS List” to “California Rare Plant Rank.” The definitions of the ranks and the ranking system have not changed, and the ranks are still used to categorize the same degrees of concern, which are described as follows:
California Rare Plant Rank 1A (formerly List 1A): Plants Presumed Extinct in California
The plants with a California Rare Plant Rank of 1A are presumed extinct because they have not been seen or collected in the wild in California for many years. This rank includes plants that are both presumed extinct as well as those plants which are presumed extirpated in California. A plant is extinct if it no longer occurs anywhere. A plant that is extirpated from California has been eliminated from California, but may still occur elsewhere in its range.
Plants are ranked 1A in an effort to highlight their plight and encourage field work to relocate extant populations. Since the publication of the fifth edition (1994), thirteen plants thought to be extinct in California have been rediscovered. These are Franciscan manzanita (Arctostaphylos franciscana), Ventura marsh milk-vetch (Astragalus pycnostachyus var. lanosissimus), San Fernando Valley spineflower (Chorizanthe parryi var. fernandina), California dissanthelium (Dissanthelium californicum), Mt. Diablo buckwheat (Eriogonum truncatum), diamond-petaled California poppy (Eschscholzia rhombipetala), Mojave tarplant (Hemizonia mohavensis), water howellia (Howellia aquatilis), Howell's montia (Montia howellii), northern adder's-tongue (Ophioglossum pusillum), Shasta orthocarpus (Orthocarpus pachystachyus), bearded popcorn flower (Plagiobothrys hystriculus), and caper-fruited tropidocarpum (Tropidocarpum capparideum). The rediscovery of these California Rare Plant Rank 1A plants is encouraging and CNPS hopes that it will motivate professional and amateur botanists alike to search for and rediscover more California Rare Plant Rank 1A species.
All of the plants constituting California Rare Plant Rank 1A meet the definitions of Sec. 1901, Chapter 10 (Native Plant Protection Act) or Secs. 2062 and 2067 (California Endangered Species Act) of the California Department of Fish and Game Code, and are eligible for state listing. Should these taxa be rediscovered, it is mandatory that they be fully considered during preparation of environmental documents relating to the California Environmental Quality Act (CEQA).
California Rare Plant Rank 1B (formerly List 1B): Plants Rare, Threatened, or Endangered in California and Elsewhere
Plants with a California Rare Plant Rank of 1B are rare throughout their range with the majority of them endemic to California. Most of the plants that are ranked 1B have declined significantly over the last century. California Rare Plant Rank 1B plants constitute the majority of taxa in the CNPS Inventory, with more than 1,000 plants assigned to this category of rarity.
All of the plants constituting California Rare Plant Rank 1B meet the definitions of Sec. 1901, Chapter 10 (Native Plant Protection Act) or Secs. 2062 and 2067 (California Endangered Species Act) of the California Department of Fish and Game Code, and are eligible for state listing. It is mandatory that they be fully considered during preparation of environmental documents relating to CEQA.
California Rare Plant Rank 2 (formerly List 2): Plants Rare, Threatened, or Endangered in California, But More Common Elsewhere
Except for being common beyond the boundaries of California, plants with a California Rare Plant Rank of 2 would have been ranked 1B. From the federal perspective, plants common in other states or countries are not eligible for consideration under the provisions of the Endangered Species Act. Until 1979, a similar policy was followed in California. However, after the passage of the Native Plant Protection Act in 1979, plants were considered for protection without regard to their distribution outside the state.
With California Rare Plant Rank 2, we recognize the importance of protecting the geographic range of widespread species. In this way we protect the diversity of our own state's flora and help maintain evolutionary processes and genetic diversity within species. All of the plants constituting California Rare Plant Rank 2 meet the definitions of Sec. 1901, Chapter 10 (Native Plant Protection Act) or Secs. 2062 and 2067 (California Endangered Species Act) of the California Department of Fish and Game Code, and are eligible for state listing. It is mandatory that they be fully considered during preparation of environmental documents relating to CEQA.
California Rare Plant Rank 3 (formerly List 3): Plants About Which We Need More Information - A Review List
The plants that comprise California Rare Plant Rank 3 are united by one common theme - we lack the necessary information to assign them to one of the other ranks or to reject them. Nearly all of the plants constituting California Rare Plant Rank 3 are taxonomically problematic. For each California Rare Plant Rank 3 plant we have provided the known information and indicated in the “Notes” section of the CNPS Inventory record where assistance is needed. Data regarding distribution, endangerment, ecology, and taxonomic validity are welcomed and can be submitted by emailing the Rare Plant Botanist at asimscnps.org or (916) 324-3816.
Some of the plants constituting California Rare Plant Rank 3 meet the definitions of Sec. 1901, Chapter 10 (Native Plant Protection Act) or Secs. 2062 and 2067 (California Endangered Species Act) of the California Department of Fish and Game Code, and are eligible for state listing. We strongly recommend that California Rare Plant Rank 3 plants be evaluated for consideration during preparation of environmental documents relating to CEQA.
California Rare Plant Rank 4 (formerly List 4): Plants of Limited Distribution - A Watch List
The plants in this category are of limited distribution or infrequent throughout a broader area in California. While we cannot call these plants "rare" from a statewide perspective, they are uncommon enough that their status should be monitored regularly. Should the degree of endangerment or rarity of a California Rare Plant Rank 4 plant change, we will transfer it to a more appropriate rank.
Very few of the plants constituting California Rare Plant Rank 4 meet the definitions of Sec. 1901, Chapter 10 (Native Plant Protection Act) or Secs. 2062 and 2067 (California Endangered Species Act) of the California Department of Fish and Game Code, and few, if any, are eligible for state listing. Nevertheless, many of them are significant locally, and we strongly recommend that California Rare Plant Rank 4 plants be evaluated for consideration during preparation of environmental documents relating to CEQA. This may be particularly appropriate for:
- The type locality of a California Rare Plant Rank 4 plant,
- Populations at the periphery of a species' range,
- Areas where the taxon is especially uncommon,
- Areas where the taxon has sustained heavy losses, or
- Populations exhibiting unusual morphology or occurring on unusual substrates.
The CNPS Threat Rank is an extension added onto the California Rare Plant Rank and designates the level of endangerment by a 1 to 3 ranking with 1 being the most endangered and 3 being the least endangered. A Threat Rank is present for all California Rare Plant Rank 1B's, 2's, 4's, and the majority of California Rare Plant Rank 3's. California Rare Plant Rank 4 plants are seldom assigned a Threat Rank of 0.1, as they generally have large enough populations to not have significant threats to their continued existence in California; however, certain conditions exist to make the plant a species of concern and hence be assigned a California Rare Plant Rank. In addition, all California Rare Plant Rank 1A (presumed extinct in California), and some California Rare Plant Rank 3 (need more information) plants, which lack threat information, do not have a Threat Rank extension.
- 0.1-Seriously threatened in California (over 80% of occurrences threatened / high degree and immediacy of threat)
- 0.2-Fairly threatened in California (20-80% occurrences threatened / moderate degree and immediacy of threat)
- 0.3-Not very threatened in California (<20% of occurrences threatened / low degree and immediacy of threat or no current threats known)
Note: The above Threat Rank guidelines only represent a starting point in the assessment of threat level. Other factors, such as habitat vulnerability and specificity, distribution, and condition of occurrences, are also considered in setting the Threat Rank.
For each taxon with official status under the California Endangered Species Act (CESA), the Federal Endangered Species Act (FESA), and/or the Native Plant Protection Act (NPPA), the plant's status is presented. Our definitions conform to those found in California state law and federal regulations.
CNDDB ELEMENT RANKING
The global rank (G-rank) is a reflection of the overall status of an element throughout its global range. Both Global and State ranks represent a letter+number score that reflects a combination of Rarity, Threat and Trend factors, with weighting being heavier on Rarity than the other two.
Species or Natural Community Level
- G1 = Critically Imperiled—At very high risk of extinction due to extreme rarity (often 5 or fewer populations), very steep declines, or other factors.
- G2 = Imperiled—At high risk of extinction due to very restricted range, very few populations (often 20 or fewer), steep declines, or other factors.
- G3 = Vulnerable—At moderate risk of extinction due to a restricted range, relatively few populations (often 80 or fewer), recent and widespread declines, or other factors.
- G4 = Apparently Secure—Uncommon but not rare; some cause for long-term concern due to declines or other factors.
- G5 = Demonstrably Secure—Common; widespread and abundant.
Subspecies receive a T-rank attached to the G-rank. With the subspecies, the G-rank reflects the condition of the entire species, whereas the T-rank reflects the global situation of just the subspecies or variety. For example: Chorizanthe robusta var. hartwegii. This plant is ranked G2T1. The G-rank refers to the whole species range i.e., Chorizanthe robusta. The T-rank refers only to the global condition of var. hartwegii.
The state rank (S-rank) is assigned much the same way as the global rank, but state ranks refer to the imperilment status only within California’s state boundaries.
- S1 = Critically Imperiled—Critically imperiled in the state because of extreme rarity (often 5 or fewer occurrences) or because of some factor(s) such as very steep declines making it especially vulnerable to extirpation from the state/province.
- S2 = Imperiled—Imperiled in the state because of rarity due to very restricted range, very few populations (often 20 or fewer), steep declines, or other factors making it very vulnerable to extirpation from the nation or state/province.
- S3 = Vulnerable—Vulnerable in the state due to a restricted range, relatively few populations (often 80 or fewer), recent and widespread declines, or other factors making it vulnerable to extirpation.
- S4 = Apparently Secure—Uncommon but not rare; some cause for long-term concern due to declines or other factors.
- S5 = Secure—Common, widespread, and abundant in the state.
- Other considerations used when ranking a species or natural community include the pattern of distribution of the element on the landscape, fragmentation of the population/stands, and historical extent as compared to its modern range. It is important to take a bird's eye or aerial view when ranking sensitive elements rather than simply counting element occurrences.
- Uncertainty about the rank of an element is expressed in two major ways:
- By expressing the ranks as a range of values: e.g., S2S3 means the rank is somewhere between S2 and S3.
- By adding a ? to the rank: e.g., S2? This represents more certainty than S2S3, but less certainty than S2.
- Other symbols:
- GH - All sites are historical; the element has not been seen for at least 20 years, but suitable habitat still exists (SH = All California sites are historical).
- GX - All sites are extirpated; this element is extinct in the wild (SX = All California sites are extirpated).
- GXC - Extinct in the wild; exists in cultivation.
- G1Q - The element is very rare, but there are taxonomic questions associated with it.
- T - Rank applies to a subspecies or variety.
Occurrence Data from DFG California Natural Diversity Database
Element Occurrence (EO)
- Element: A plant, animal, or natural community tracked by the natural heritage program.
- Occurrence: The specific location(s) where an element is known to occur.
Definition of plant EOs in California: A population or group of populations found within 0.25 miles and not separated by significant habitat discontinuities.
Total # of Known Element Occurrences / Occurrence Count
The current number of occurrences for a particular element.
Element Occurrence Ranks
An element’s Occurrence Rank is a ranking of the quality of the habitat and the condition of the population at that location. The possible values for Occurrence Rank are:
- A - Excellent
- B - Good
- C - Fair
- D - Poor
- X – None (extirpated or possibly extirpated element occurrences)
- U - Unknown
Displays number of element occurrences that have been seen and/or not seen within the past 20 years. Element occurrences that have not been seen within the past 20 years are considered historic.
Presence refers to the condition of the occurrence at the site when it was last observed. The possible values for Presence are:
- Presumed Extant: The most common entry. An occurrence is presumed to still be in existence until evidence to the contrary is received by the CNDDB.
- Possibly Extirpated: Evidence of habitat destruction or population extirpation has been received by the CNDDB for this site, but questions remain as to whether the element still exists.
- Extirpated: Only used when the element has been searched for but not seen for many years or when the habitat is destroyed at this site.
A brief description of plant duration and life form. The information is primarily developed from published and unpublished literature and from herbarium material. Our simplified classification system is as follows:
- Annual: Grows from seed and reproduce within a single year.
- Perennial: Lives more than one year.
(Annual/Perennials are variable depending on environment and conditions.)
- Herbs: Plants that are herbaceous and lack above-ground woody tissue.
- Bulbiferous herb: Plants have fleshy underground storage organs typically derived from scale leaves (this category includes cormiferous and other similar plants in which storage organs have other origins).
- Rhizomatous herb: Plants have underground stems (rhizomes), typically bearing shoots which develop into new plants.
- Stoloniferous herb: Plants have above-ground runners (stolons) which typically root and produce new plants.
- Shrubs: Smaller woody perennials that retain most of their above-ground woody tissue and are typically many-stemmed.
- Leaf succulents: Succulents with thick, fleshy leaves.
- Stem succulents: Succulents with thick, fleshy stems and reduced or absent leaves.
- Trees: Larger woody perennials that retain all of their above-ground wood tissue and are typically single-stemmed.
- Vines: Twining woody perennials requiring external support for growth.
- Mosses: Small green plants (one of three groups of bryophytes) with structures that resemble miniature leaves and stems. The leaves generally have a midrib called a costa. The sporophyte (the spore-bearing structure) is persistent for weeks.
- Liverworts: Small green plants (one of three groups of bryophytes). There are both leafy and thalloid types - leafy liverworts lack a midrib on the leaves, while thalloid liverworts have no leaves. The sporophyte is short-lived.
- Leaf Condition (for shrubs, trees, vines only):
- Deciduous: Plants shed their leaves for part of the year.
- Evergreen: Plants retain their leaves for an entire year.
- Special Habitat:
- Aquatic: Plants are submerged or floating on the water surface.
- Emergent: Plants are rooted in water but bear some foliage out of the water.
- Mode of Nutrition:
- Achlorophyllous: Plants lack chlorophyll and live on existing organic matter in the soil.
- Hemiparasitic: Plants are connected to host plants and derive energy, water, and minerals from them, but also maintain their own functional root systems or photosynthetic surfaces.
- Parasitic: Plants are connected to host plants and rely solely on them for energy, water, and nutritional requirements.
- Carnivorous: Plants trap insects and other small animals and derive nourishment from them.
As in most classifications, some of the above distinctions are somewhat arbitrary, particularly the divisions between growth forms. Furthermore, plant growth form can vary depending on geography and local environmental conditions. Perennials that are often referred to as either suffrutescent herbs or subshrubs present special difficulties. Generally, if these plants die back seasonally to the ground or to a small crown of woody tissue we classify them as herbs, and if they retain much or all of their woody above-ground tissue we call them shrubs.
The month(s) when each rare plant is typically in bloom. For ferns and other spore-bearing plants, we give the months when spores are released and spore-bearing structures such as sori are typically present on the plant. We do not included any comparable information for gymnosperms and nonvascular taxa.
Note: Months in parentheses are uncommon.
One or more habitats in which a rare, threatened, or endangered plant is typically found. This information is compiled from field survey forms, unpublished reports, original descriptions, floras, and herbarium material. Note that for habitats which typically occur within a broader matrix of another habitat, we usually list both. For example, a rare plant from Meadows and Seeps occurring in a matrix of Upper Montane Coniferous Forest would typically have its habitat presented as "Meadows and Seeps, Upper Montane Coniferous Forest."
Habitats follow brief characterizations outlined by Robert F. Holland and John O. Sawyer, Jr. and are presented in taxonomic rather than alphabetical order. Please refer to Holland (1986) for a more complete discussion of the types and their classification.
- Coastal dunes (CoDns): Herbs or shrubs on coastal sand deposits from Del Norte to San Diego counties. Cover usually low near the beach, increasing with distance from salt spray and blowing sand.
- Desert dunes (DeDns): Sand accumulations east of the Pacific Crest from Modoc to Imperial counties. Vegetation on desert dunes varies considerably. Active dunes usually support only sparse herbs and grasses, but partially stabilized or stabilized dunes often will support shrubs, including mesquite and creosote bush.
- Inland dunes (InDns): Mostly herbs, although shrubs may be locally important. Sand accumulations in and around the Great Valley.
- Coastal bluff scrub (CBScr): Dense shrubs, prostrate to 1-2 meters tall. Typically on fairly steep, rocky sites exposed to considerable wind and salt spray because of proximity to the ocean. Many plants succulent, especially to the south. Found from Del Norte to San Diego counties.
- Coastal scrub (CoScr): Dense shrubs 0.5 to 2 meters tall with scattered grassy openings. Many plants dormant, even deciduous, during periods of water stress. Most sites have shallow rocky soils, frequently with a southern or western exposure. Many taxa adapted to fire by stump sprouting or high seed production.
- Sonoran desert scrub (SDScr): Widely scattered creosote bushes with the considerable space between them sometimes occupied by ephemeral, colorful shows of annuals following particularly wet winters. Succulents and microphyllous trees conspicuous, especially in rocky environments. The part of Munz’s (1959) "Creosote bush scrub" found roughly south of the San Bernardino / Riverside county line.
- Mojavean desert scrub (MDScr): Widely scattered creosote bushes with the considerable space between them sometimes occupied by ephemeral, colorful shows of annuals following particularly wet winters. At elevations of 600 meters or higher, succulents or microphyllous trees lacking. This habitat type constitutes most of Munz’s (1959) "Creosote bush scrub" found north of the San Bernardino / Riverside county line.
- Great Basin scrub (GBScr): Shrubs, ranging in height from very short, <20 centimeters, on very cold sites or shallow soils to 1 or 2 meters tall on warmer sites where soils are deeper. Perennial grasses occupy much of the space between shrubs. Found on the Modoc Plateau, high Cascade Range, Warner Mountains, High Sierra Nevada, and North Coast Ranges.
- Chenopod scrub (ChScr): Usually gray, intricately branched, microphyllous shrubs most commonly on fine-textured, alkaline and/or saline soils in areas of impeded drainage. Diversity usually low to monotonous. Saltbushes and greasewood frequently dominate. This vegetation occurs from Modoc County south to Mexico, including parts of the Great Valley and Inner South Coast Ranges.
- Chaparral (Chprl): Impenetrably dense, evergreen, leathery-leaved shrubs that are active in winter, dormant in summer, and adapted to frequent fires either through resprouting or seed carry-over. There is a characteristic florula of fire-following annuals and short-lived perennials. Mature stands may exceed 3-4 meters in height. It occurs on diverse substrates, many of which support distinctive suites of edaphic indicators. Chaparral may be successional to conifer forests or oak woodlands, as tree seedlings can be found beneath the shrub canopies.
- Coastal prairie (CoPrr): Dense, fairly tall (<1 meter) perennial sod- and tussock-forming grasses and grass-like herbs. They occur in two distinct settings: sandy marine terraces within the zone of coastal fog (usually <350 meters elevation, within a matrix of Northern Coastal Scrub), or on fine-textured soils of ridgetops beyond coastal fogs (usually >750 meters, within a matrix of Mixed Evergreen or North Coastal Conifer Forests). Intermittent from the Santa Cruz area north to southern Oregon.
- Great Basin grassland (GBGrs): Perennial sod-forming and bunch grasses. Presumed to have once been widespread on the Modoc Plateau and northeastern California. Currently represented as scattered, mostly small, islands in areas where grazing pressure has been low and fire frequencies higher than surrounding scrubs. Both upland and bottom-land forms occur.
- Valley and foothill grassland (VFGrs): Introduced, annual Mediterranean grasses and native herbs. On most sites the native bunch grass species, such as needle grass, have been largely or entirely supplanted by introductions. Stands rich in natives usually found on unusual substrates, such as serpentinite or somewhat alkaline soils.
- Vernal pools (VnPls): Seasonal amphibious environments dominated by annual herbs and grasses adapted to germination and early growth under water. Spring desiccation triggers flowering and fruit set, resulting in colorful concentric bands around the drying pools.
- Meadows and seeps (Medws): More or less dense grasses, sedges, and herbs that thrive, at least seasonally, under moist or saturated conditions. They occur from sea level to treeline and on many different substrates. They may be surrounded by grasslands, forests, or shrublands.
- Playas (Plyas): Non-vascular plants and sparse, gray shrubs on poorly drained soils with usually high salinity and/or alkalinity, due to evaporation of water from closed basins. Found from the Modoc Plateau to Sonoran Desert and in the San Joaquin Valley.
- Pebble (Pavement) plain (PbPln): Herb- and grass-dominated openings of low cover, dominated by several cushion-forming plants endemic to dense, clay soils armored by a lag gravel of quartzite pebbles. Many of the dominant taxa are themselves rare plants. Found only in the San Bernardino Mountains.
- Bogs and fens (BgFns): Wetlands, typically occupying sites sub-irrigated by cold, frequently acidic, water. Plant growth dense and low growing, dominated by perennials herbs or low shrubs. Saturated soils frequently allow substantial accumulations of "peat." From the Klamath Ranges to North Coast Ranges, along the North Coast and in the northern Sierra Nevada.
- Marshes and swamps (MshSw): Emergent, suffrutescent herbs adapted to seasonally or permanently saturated soils. These include salt, brackish, alkali, and fresh water marshes, as well as swamps, with their woody dominants and hydrophytic herbs. Found throughout California.
- Riparian forest (RpFrs): Broadleaved, winter deciduous trees, forming closed canopies, associated with low- to mid-elevation perennial and intermittent streams. Most stands even-aged, reflecting their flood-mediated, episodic reproduction. These habitats can be found in every county and climate in California.
- Riparian woodland (RpWld): Broadleaved, winter deciduous trees with open canopies associated with low- to mid-elevation streams. Most stands even-aged, reflecting their flood-controlled, episodic reproduction. This type tends to occupy more intermittent streams, often with cobbly or bouldery bedloads.
- Riparian scrub (RpScr): Streamside thickets dominated by one or more willows, as well as by other fast-growing shrubs and vines. Most plants recolonize following flood disturbance.
- Cismontane woodland (CmWld): Trees deciduous, evergreen, or both, with open canopies. Broadleaved trees, especially oaks, dominate, although conifers may be present in or emergent through the canopy. Understories may be open and herbaceous or closed and shrubby. This type occurs on a variety of sites below the conifer forests in Mediterranean California.
- Pinyon and juniper woodland (PJWld): Open stands of round-topped conifers to 5 meters. Understories frequently comprised of shrubs and herbs seen in adjacent stands lacking trees. They often form broad ecotones between higher elevation forests and lower elevation scrublands or grasslands.
- Joshua tree "woodland" (JTWld): Joshua trees with open canopies are usually the only arborescent species present. Shrubstories typically are diverse mixtures of microphyllous, evergreen shrubs, semi-deciduous shrubs, semi-succulents, and succulents.
- Sonoran thorn woodland (STWld): Succulents, microphyllous herbs and shrubs, especially of rocky environments. Tree-like plants the visual dominant.
- Broadleafed upland forest (BUFrs): Stands of evergreen or deciduous, broadleaved trees 5 meters or more tall, forming closed canopies. Many, but not all, with very poorly developed understories. Several are seral to montane conifer forests. It includes the "mixed evergreen forest" of the Coast Ranges.
- North Coast coniferous forest (NCFrs): Needle-leaved evergreen trees in usually quite dense stands that may attain impressive heights. Usually on well-drained, moist sites within the reach of summer fogs, but not experiencing much winter snow. This type occurs in the wetter parts of the North Coast Ranges.
- Closed-cone coniferous forest (CCFrs): Dense, even-aged stands dominated by serotinous-coned conifers. Most stands are even-aged due to fire establishment. Usually associated with sterile, rocky soils, strong and steady winds, and impaired drainage. Many open stands have understories composed of chaparral or coastal scrub species from surrounding areas. Found in most areas, except for the Great Valley or deserts.
- Lower montane coniferous forest (LCFrs): Open to dense stands of conifers found at lower and middle elevations in the mountains. Broadleaved trees may be present in the understory. Shrubstories may be dense assemblages of chaparral species, especially in seral stands. The upper limit of lower montane coniferous forests more or less coincides with the elevation of maximum annual precipitation.
- Upper montane coniferous forest (UCFrs): Open to dense conifer forests, found at high elevations in the mountains. Trees tend to be somewhat shorter than at lower elevations. Shrubstories tend to be open, drawn from adjacent montane chaparral species, or lacking. Above the elevation of maximum precipitation, with growing seasons curtailed by winter snow accumulations.
- Subalpine coniferous forest (SCFrs): Conifer forests and associated clearings of highest elevations of tree establishment. This type occurs in areas where substantial snowpack accumulation and cold temperatures limit the growing season to three months or less.
- Alpine boulder and rock field (AlpBR): Fell-fields, talus slopes, and meadows found above forest line. Favorable sites may develop continuous turf, but in most areas plants are tucked between large nurse rocks that provide protection from harsh winter conditions.
- Alpine dwarf scrub (AlpDS): Compact, woody subshrubs above forest line, adapted to short growing seasons resulting from snow accumulation or harsh winter winds.
Descriptors that denote substrate type, hydrological information, etc., are often used to modify habitat types as follows:
- "(descriptor)" pertains only to the habitat type immediately preceding
- "descriptor" prior to habitat types pertains to all habitats
freshwater (used for Marshes and Swamps)
coastal salt (used for Marshes and Swamps)
maritime (used for Chaparral)
The distribution of the taxon is described by county or island within California, together with other states and countries where we know the plant to exist. We record only natural occurrences of rare plants, or occurrences that have been reestablished within the species' historic range as part of an approved recovery plan. For example, although both Northern California black walnut (Juglans hindsii) and Monterey pine (Pinus radiata) are widely planted within the state, we track only the few natural occurrences of these taxa. When we indicate that a particular plant occurs in a particular county, we are making a positive statement that is based upon specimens, photographs, the literature, or field observations. In no way does this imply that a plant does not occur in other counties in California or in other states. Our understanding of plant distribution constantly improves, and new localities for rare plants are discovered often in unpredicted circumstances.
The following symbols are used as modifiers preceding counties, quads, and/or states to express extirpation and/or uncertainty:
- * Presumed extirpated
- ? Uncertain about distribution or identity
- ?* Uncertain about distribution, but presumed extirpated if once present
- (?) Occurrence confirmed, but possibly extirpated
Counties and Islands
Three letter codes have been attributed for each county and island within California to maintain and manage swift data control of the Inventory. In turn, these codes are used as abbreviations in the "Notes" section on the plant detail page for some taxa.
County and Island Codes:
ANA Anacapa Isl.
CCA Contra Costa
DNT Del Norte
ELD El Dorado
FAR Farallon Isl.
LAX Los Angeles
| MEN Mendocino
SBA Santa Barbara
SBD San Bernardino
SBR Santa Barbara Isl.
SBT San Benito
SCL Santa Clara
SCM San Clemente Isl.
SCT Santa Catalina Isl.
SCR Santa Cruz
SCZ Santa Cruz Isl.
SDG San Diego
SFO San Francisco
BA Baja California
To provide more detailed location information, we cite the U.S. Geological Survey (USGS) 7.5 minute quadrangle (quad) map for all plants on CNPS Lists 1, 2, and 3, as well as some plants on List 4 (please see warning about quad maps for List 4’s below). We employ a modified version of the quad numbering system previously used by the California Department of Water Resources. Please follow this link to translate this system's quad numbers into USGS topographic map names or vice versa. In those few cases where a quad is listed without a letter following the number, this indicates that our occurrence data are too vague to pinpoint its location on a 7.5 minute quadrangle. As with counties, this is positive siting information - when we indicate that a plant has been reported from an area on a topographic quad, it is based on hard data. In no way does this imply that a plant does not occur on a topographic quad we have not listed; rather, it may be there but botanists have yet to find it. As with distribution, quads are also often modified with the symbols "*" and "?", which respectively express extirpation and uncertainty (see above).
Quad data is not available for all List 3 and 4 plants. For those that do contain this data, it has not been quality controlled and is potentially incomplete, inaccurate, and/or out of date. Please use caution when referencing this information. We are currently working hard to maintain this data and hope to provide accurate and up to date information in the near future.
An elevational range is provided for each taxon in meters. The stated range is for the California portion of a plant's range only (if the taxon also occurs outside the state). These elevational range data are accumulated from literature, herbarium specimens, and field survey information.
Many entries include additional notes on distribution, endangerment, relationship to names in The Jepson Manual, or important literature citations. We again include information about legal status and endangerment in neighboring states in the notes; official state designations are specifically indicated as such and capitalized, as in "State-listed as Endangered in OR". We make a special effort to indicate missing information about distribution, endangerment, or taxonomy for each entry, in the hope that knowledgeable users will fill in the gaps.
Abbreviations that are commonly used in the notes include:
|ACEC||Area of Critical Environmental Concern||NF||National Forest|
|AFB||Air Force Base||NM||National Monument|
|BA||Botanical Area||NP||National Park|
|BLM||Bureau of Land Management||NS||National Seashore|
|CalTrans||California Department of Transportation||Pk.||Peak|
|DFG||California Department of Fish and Game||RNA||Research Natural Area|
|DOD||United States Department of Defense||SP||State Park|
|ER||Ecological Reserve||SR||State Reserve|
|Ft.||Fort||TCF||The Conservation Fund|
|FNA||Flora of North America||TJM (1993)||The Jepson Manual: Higher Plants of California|
|HCP||Habitat Conservation Plan||TJM 2||The Jepson Manual: Vascular Plants of California, Second Ed.|
|Mt.||Mount||TNC||The Nature Conservancy|
|Mtn.||Mountain||USFS||United States Forest Service|
|Mtns.||Mountains||USFWS||United States Fish and Wildlife Service|
|NA||North America||WA||Wildlife Area|
Threats: Includes information on significant threats to the plant over its range in California. Typical threats provided in the notes section include, but are not limited to the following:
alteration of fire regimes
- ^ Abrams, L.R. 1923-1960. An Illustrated Flora of the Pacific States, Washington, Oregon and California. Vol. 4 by R. Ferris. Stanford University Press. Stanford, CA. 4 vols.
- ^ California Department of Fish and Game, Natural Diversity Database. 2010. Metadata Description of CNDDB fields. RareFind 4 internet application. Accessed November 5, 2010.
- ^ California Department of Fish and Game, Natural Diversity Database. 2010. Special vascular plants, bryophytes, and lichens list. Quarterly publication, October 2010. 85 pp. Available online at: http://www.dfg.ca.gov/biogeodata/cnddb/pdfs/SPPlants.pdf.
- ^ Hickman, J.C., ed. 1993. The Jepson Manual: Higher Plants of California. University of California Press. Berkeley, CA. 1400 pp.
- ^ Holland, R.F. 1986. Preliminary Descriptions of the Terrestrial Natural Communities of California. Nongame-Heritage Program, California Department of Fish and Game. Sacramento, CA. 156 pp.
- ^ Kartesz, J.T., and J.W. Thieret. 1991. Common names for vascular plants: Guidelines for use and application. Sida 14(3):421-434.
- ^ Munz, P.A. 1959. A California Flora. In collaboration with D.D. Keck. University of California Press. Berkeley, CA. 1681 pp.
- ^ Munz, P.A. 1968. Supplement to a California Flora. University of California Press. Berkeley, CA. 224 pp.
- ^ Munz, P.A. 1974. A Flora of Southern California. University of California Press. Berkeley, CA. 1086 pp.
- ^ Shevock, James R. 1993. How plants get their names and why names change. Fremontia 21(1):19-24.
- ^ Skinner, Mark W. and Barbara Ertter. 1993. Whither rare plants in The Jepson Manual? Fremontia 21(3):23-27.