|Scientific Name:||Hydrastis canadensis L.|
|Taxonomic Notes:||Hydrastis is sometimes placed in its own family, Hydrastidaceae, with one other monotypic genus, Glaucidium, which is restricted to Japan (Tobe 2003). However, under the Angiosperm Phylogeny scheme, they are placed under Ranunculaceae (Stevens 2001).|
|Red List Category & Criteria:||Vulnerable A2cd+4cd ver 3.1|
|Reviewer(s):||Leaman, D.J. & Sinclair, A.|
Goldenseal is a long-lived, perennial plant that occurs only in North America, where it has undergone a decline in the area of occupancy and habitat quality. Goldenseal is also threatened by wild-collection for domestic and international medicinal use and by deer browsing. The species is considered Vulnerable based on a past and ongoing population reduction of at least 30% over three generations (approximately 21-27 years) inferred from past and ongoing declines in area of occupancy and habitat quality, and from documented levels of exploitation.
|Range Description:||Goldenseal occurs in North America in the United States and Canada. It ranges from southern Vermont northward to Ontario, west to Minnesota and south to Georgia, Alabama, and Arkansas. It is common in Arkansas, Indiana, Illinois, Kentucky, Missouri, Ohio, and West Virginia; uncommon around the range perimeter. Goldenseal was historically and is currently abundant in the central portion of its range including Indiana, Kentucky, Ohio, and West Virginia (Sinclair and Catling 2000a). Christensen and Gorchov (2010) describe the core part of the historical range as the Ohio River Valley. In Canada, it occurs only in southwestern Ontario (Sinclair and Catling 2000a).|
Decline in the species area of occupancy is due to land-conversion beginning in the mid-1800s. In the mid-1800s, populations throughout Goldenseal's range dramatically declined due to collection for medicinal uses and habitat destruction (Mulligan and Gorchov 2004). There is anecdotal evidence from this period that the decline and loss of Goldenseal populations, from market-demand and loss of habitat, put greater collection pressure on managed or previously unharvested subpopulations (Albrecht and McCarthy 2006). In the Canadian portion of its range, less than 5% of Goldenseal's forest habitat remains from pre-settlement times (Sinclair and Catling 2000a). Similarly in New England, forest conversion reached its height during the 1800s when approximately 80% of the originally forested land was lost (Tait 2006). While land-conversion has slowed since then, habitat loss remains a threat to this species throughout its range (Sinclair and Catling 2000a; pers. comm. State Natural Heritage Botanists in Alabama, Indiana, Kentucky, Michigan, Missouri, Mississippi, New York, Ohio, Pennsylvania, Virginia, Vermont, and Wisconsin). Additionally, botanists have documented declines in the area of occupancy and subpopulations in the recent past in its core range. For example, Mulligan and Gorchov (2004) document loss of approximately 29% of subpopulations in Ohio from late 1977 through 1998, including 31 extirpated subpopulations. Of these extirpations, only nine were due to deforestation, meaning causes other than land-conversion led to the loss of other subpopulations.
Native:Canada (Ontario); United States (Alabama, Arkansas, Connecticut, Delaware, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, New Jersey, New York, North Carolina, Ohio, Pennsylvania, Tennessee, Vermont, Virginia, West Virginia, Wisconsin)
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||Goldenseal reproduces clonally and sexually, with >1,000,000 ramets (clonal individuals) known. The count of ramets (genetically identical stems) should be considered carefully to avoid suggesting the species is secure based on population size. There are at least 1,000 extant subpopulations in the United States and 22 extant subpopulations in Canada (NatureServe 2012), but subpopulations may have very low genetic diversity. Therefore, the count of subpopulations or 'patches' should be considered cautiously. However, small subpopulations should be considered important for the conservation of the species as they can be long-lived and are sources of genetic variability for other nearby sybpopulations (Sanders 2004).|
In the mid-1800s, subpopulations of Goldenseal experienced significant declines from habitat conversion to agricultural land and wild collection for medicinal purposes (Mulligan and Gorchov 2004). Over the long-term, once-abundant populations were decimated, and the distribution of this widespread species was reduced to isolated, scattered patches in parts of its range (Mulligan and Gorchov 2004, Foster 1991, Henkel and Klugh 1904). For example, in New England approximately 80% of the originally forested land was lost during the 1800s, when conversion of forested lands to agriculture and settlement reached its height (Tait 2006). There are only remnants of the woodlands remaining where Goldenseal occurs in Canada: less than 5% of these forests remain from pre-settlement times (Sinclair and Catling 2000a). State-by-state abundance of Goldenseal in the United States is unknown, which is typical for most wild-harvested plant species (McGraw et al. 2003). Long-term and recent short-term population decline has been inferred from observed decline in the area of occupancy. In Ohio, a state in the core of Goldenseal's range, a study undertaken by Mulligan and Gorchov (2004) found that nearly half of 71 historical locations were extirpated. Of the 42 Goldenseal sites documented in Ohio from 1977-1998, 14 sites were extirpated as of 2002. If the rate of decline is constant, approximately 1.6% of subpopulations are expected to be extirpated each year, with approximately a 30% decline over 20 years (Mulligan and Gorchov 2004, G. Gorchov pers. comm. 2012).
Continuing decline in Goldenseal subpopulations is exacerbated by wild collection. Mulligan and Gorchov (2004) note that Ohio, Goldenseal is comprised of more small subpopulations with fewer flowering plants than Goldenseal in Ontario, and suggest that the difference may be attributed to wild collection being permitted in Ohio rather than prohibited in Ontario. In Ohio subpopulations, flowering individuals transitioned to large sterile individuals in the year following reproduction, and back to flowering individuals later, presumably due to the energy cost of flowering (Christensen and Gorchov 2010). If collectors remove the largest individuals from subpopulations, either sterile or fertile, future recruitment and population growth are adversely affected (Christensen and Gorchov 2010). Over time, subpopulations would become smaller with fewer flowering or larger individuals as documented in the Mulligan and Gorchov (2004) study. Other declines in subpopulations have been qualitatively documented in New York, West Virginia, and Indiana (Tait 2006, Sanders and McGraw 2005, P. Harmon pers. comm., Indiana Department of Natural Resources pers. comm.).
Additional recent and scattered short-term declines are documented in Goldenseal's range. Subpopulation decline is evidenced through fewer subpopulations present, fewer patches per subpopulation, and fewer ramets per patch (Sanders and McGraw 2005). In New York, recent studies have shown on-going extirpations as the distribution was reduced from 14 to 12 counties due to habitat loss (Tait 2006). In West Virginia, evidence of poaching was documented near Morgantown, West Virginia (Sanders and McGraw 2005). These extirpations represent a reduction in the area of occupancy. In Indiana, another state in the species' core portion of its range, recent increases in wild-collection are causing concern (Indiana Department of Natural Resources pers. comm. 2012). It is expected that there are other undocumented short-term declines in portions of the species' range where habitat loss and wild-collection are occurring at high levels.
These trends are likely to continue as there is continued demand for wild collected Goldenseal. In the 2010 tonnage report from the American Herbal Products Association an average of 50 tons of dried root (both cultivated and wild combined) is reported between 1998 and 2010, while also noting that market demand was steady during this 13-year period (AHPA 2010). Further, between 1998 and 2010, an average of 77% or 38 tons of the yearly volume purchased was from wild collected Goldenseal (AHPA 2010). It should be noted that these metrics represent a fraction of the wild-collected Goldenseal.
|Current Population Trend:||Decreasing|
|Habitat and Ecology:||Habitat: In the United States Goldenseal is found in rich, densely shaded, deciduous forests with good airflow and water drainage (Greenfield and Davis 2012). Light gaps and soil disturbance stimulate local proliferation (McGraw et al. 2003). In Southwest Ontario Goldenseal is limited to deciduous woodlands near floodplains and periodic spring-flooded plateaus. Less than 5% of these forests remain from pre-settlement times (Sinclair and Catling 2000a,b).|
Biology: Goldenseal reproduces both clonally and sexually, with clonal division more frequent than sexual reproduction. The first growth stage begins when the seed erupts and cotyledons emerge; plants can remain in this state one or more years. The second vegetative stage occurs during years two and three (and sometimes longer) and is characterized by the development of a single leaf and absence of a well developed stem. The third stage is reproductive, at which point flowering and fruiting occurs. This last stage takes between four and five years to develop (Burkhart and Jacobson 2006).
Flowers appear in April through May, and fruits from June through July (Sinclair et al. 2000, Eichenberger and Parker 1976). Goldenseal has a mixed-breeding system in which selfing and outcrossing occur (Sanders 2004, Sinclair et al. 2000). Levels of fruit and seed set in one study were equal in selfing and outcrossing events (Sanders 2004). In southwest Ontario, the northern extent of Goldenseal's range, seedlings are rare (Sinclair and Catling 2000a). A study in Ohio found that while there were fewer seedlings than ramets, a substantial number of seedlings succeeded to the next life history stage (Christensen and Gorchov 2010). This ultimately represents an infusion of genetic diversity into the otherwise highly clonal population (Christensen and Gorchov 2010). Additionally, Christensen and Gorchov (2010) noted that seedling rarity was not due to infrequent flowering, low fruit or seed set, or low seed viability.
|Continuing decline in area, extent and/or quality of habitat:||Yes|
|Generation Length (years):||7-9|
|Use and Trade:||
Goldenseal is collected for trade in the medicinal market. Goldenseal roots, leaves, seeds, fruits, and whole plants are sold as fresh, powdered, or dried material (Egert 2007). The rhizomes and leaves (or aerial parts) of Goldenseal are used for medicinal purposes. Rhizomes seem to be the preferred target for harvest because they have the highest concentration of medicinally-active alkaloids (berberine, hydrastine and canadine). Leaves and stems contain lower levels of these alkaloids (Douglas et al. 2010).
The demand for Goldenseal due to its medicinal qualities continues to rise. While Goldenseal has been cultivated for 100+ years, much of the material traded both domestically and internationally still comes from wild-harvested plants (Christensen and Gorchov 2010). As of 2005, nearly all of the wild-collected material was collected by small-scale diggers from the southern Appalachian range and Missouri, and 40% of the overall supply of Goldenseal was from cultivated material (Greenfield and Davis 2012). The high prices paid for wild-collected roots and rhizomes in the herbal market has increased collection pressure, especially in parts of the species' range where unemployment is high (McGraw et al. 2003).
In recent years, there has been a shift in the international market from mostly wild-harvested to cultivated sources. In 1998, the American Herbal Products Association (AHPA) recorded only 2% of material in trade from cultivated sources. The CITES Trade Database (2000-2013) indicates that much of the legally harvested material in international trade now originates from cultivated plants, indicating an increase of up to 41% cultivated Goldenseal between 2000-2010. Cultivated Goldenseal also comprises a large portion of domestic trade; however, the amount of wild-harvested rhizomes collected and traded in the United States is unknown. The market for Goldenseal is expected to grow at a rate of 5% to 10% annually, and the market for high quality cultivated material is expected to grow 10 to 15% annually (Greenfield and Davis 2012).
Goldenseal is threatened primarily by destruction of habitat, decline in habitat quality, wild-collection, and deer browsing. Habitat destruction is a primary threat throughout the species' range. Sinclair and Catling (2000a) report that the survival of Goldenseal subpopulations is threatened by clearing woodlots for residential development; only 5% of forested habitat remains that supports Goldenseal in Canada. The situation is similar throughout New England where habitat destruction is a major threat (Natural Heritage Botanists pers. comm. in 2012, Tait 2006). Local extinctions in Ohio are likely the result of urban sprawl (Mulligan and Gorchov 2004). Decline in the quality of habitat is due to on-going agricultural expansion, road building, urbanization, and recreational use of forests (Mulligan and Gorchov 2004). Other habitat-associated threats include extirpation of seed dispersers and loss of natural disturbance (soil disturbance, moisture and nutrient inputs from flooding and fire), that promotes population growth and dispersal (Sinclair and Catling 2000a).
Goldenseal is threatened by wild-harvest for domestic and international medicinal plant markets (Sinclair and Catling 2000a, McGraw et al. 2003, pers. comm. Indiana Department of Natural Resources). Although the amount of cultivated material in trade is increasing (American Herbal Products Association 2004-2005), wild collection remains an important source of income in parts of the species' range where unemployment is high (Greenfield and Davis 2012, McGraw et al. 2003). In Indiana, collection pressure has intensified dramatically over the last 10 years, based on the number of inquiries by herbal diggers in the state (Indiana Department of Natural Resources pers. comm.). Law enforcement officials in Indiana are concerned about the species based on the quantity of material exported from the state. Although there are no quantitative data on population declines in Indiana, declines are likely (Indiana Department of Natural Resources pers. comm.). Studies suggest that if as little as 10% of the plants from a wild populations are removed annually, these populations will go extinct over time (Mulligan and Gorchov 2004).
Invasive and non-native plant species are also a threat. White-tailed Deer browsing is a threat in Ohio (Mulligan and Gorchov 2004) and in other parts of the range. Albrecht and McCarthy (2006) report observations by botanists in the early 19th century of Goldenseal population disappearance due to the co-occurrence of over-collection and habitat loss. The combination of these two threats may reduce or reverse positive efforts of stewardship or management (Albrecht and McCarthy 2006). Where these two threats are actively co-occurring, the rate of decline may increase.
Goldenseal is used for a variety of medicinal purposes and is under pressure from wild-harvest in domestic and international markets. Over-collection is a concern in both the United States and Canada. Goldenseal was listed in Appendix II of CITES (Convention for International Trade on Endangered Species of Wild Fauna and Flora) in 1997 due to concern over wild-collection, with an annotation to regulate roots. Its annotation was amended in 2007 to clarify that the listing applied to international trade of underground parts (roots and rhizomes including whole, parts, and powdered). A CITES Appendix-II listing requires that exporters obtain export permits or certificates for international trade. These permits are issued when specimens are considered legally acquired and international trade is considered not detrimental to the survival of the species in the wild.
Goldenseal was designated as Threatened by COSEWIC (Committee on the Status of Endangered Wildlife in Canada) in 1991 and re-assessed as Threatened by COSEWIC in 2000. Goldenseal receives protection under Ontario's Endangered Species Act and the Canadian federal Species at Risk Act (SARA). There is no federal protection for Goldenseal in the United States. However, many sites throughout the species' range are on land managed by federal, state, local, or private organizations, including some populations within Nature Conservancy preserves. Plants on public and protected lands need greater protection from illegal collecting. Existing regulations protecting plants on public and protected lands need better enforcement.
|Citation:||Oliver, L. 2017. Hydrastis canadensis. The IUCN Red List of Threatened Species 2017: e.T44340011A44340071.Downloaded on 24 September 2018.|
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