Sustainability of Chinese Herbal Medicine
According to the US Environmental Protection Agency, sustainability is based on a simple principle: Everything that we need for our survival and well-being depends, either directly or indirectly, on our natural environment. To pursue sustainability is to create and maintain the conditions under which humans and nature can exist in productive harmony to support present and future generations.
As reported in Chinese Medicine in 2016, 78% of the top selling 150 drugs in the US were originally derived from plant sources. Herbal drugs provide solutions for the primary healthcare needs of up to 80 % of people in developing countries, and over 25% of prescribed medicines in developed countries are derived from wild plant species. The International Union for Conservation of Nature and the World Wildlife Fund estimates there are between 50,000 and 80,000 flowering plant species used for medicinal purposes worldwide. Of these, about 15,000 species are threatened with extinction from overharvesting, habitat destruction, and climate change. 20% of the wild resources have already been nearly exhausted with increasing human population, uncontrolled deforestation, urbanization, and plant consumption due to ever escalating demand. This threat has been known for nearly forty years and it particularly affects Chinese herbs, which includes about 8000 plants that are gathered and harvested for use in herbal medicine.
What is Being Done?
Since herbs are becoming scarcer in the wild, many nations, including China, are undertaking initiatives to protect against the accelerated loss of species.
- In situ conservation. Many medicinal plants are endemic species that grow best in geo-authentic areas. In China this is referred to as dào dì (道地) Their medicinal properties are due mainly to the presence of secondary metabolites that respond to stimuli in natural environments, such as soils, rainfall, hours and days of sunshine, understory, and the presence of other unique factors. In many cases, these secondary metabolites may not be expressed under cultivated conditions. Consequently, efforts are being made to expand these natural habitats or find similar habitats in which to introduce species. China, in particular, is providing seed stock to expand introduction of threatened species in natural habitats.
The advantages to fostering the growth of wild species in situ include the obvious lack of need to invest in the resources necessary for cultivation, including the use of fertilizers and pesticides. There is also an understood belief, which may not always be true, that wild resources are more therapeutically efficacious.
- Nature reserves. Natural reserves are protected areas of important wild resources created to preserve and restore biodiversity. Currently, approximately 9% of the Earth’s land surface has been designated as protected areas. The resources of these areas may not always be available for commercial use, but they can provide a reservoir for biodiversity.
- Wild nurseries. Often it is not possible to designate natural wild habitats as reserves due to the high cost of land and competing land uses. Wild nurseries and botanical gardens can provide a haven for threatened species in smaller tracts near dào dì regions where the herbs are endemic.
- Ex situ conservation. The intent of ex situ conservation, meaning to grow herbs outside their traditional dào dì regions, is cultivation and naturalization of threatened species to ensure their continued survival and sometimes to produce large quantities of planting material used in the creation of drugs. Cultivation practices are designed to provide optimal levels of water, nutrients, optional additives, and environmental factors including temperature, light, and humidity to obtain improved yields of target products. Often, it is an immediate action taken to sustain medicinal plant resources and is increasingly used throughout China. Cultivation also provides the opportunity to use new techniques to solve problems routinely encountered in the production of medicinal plants; such as toxic components like heavy metals, pesticide contamination, low content of active ingredients, and the misidentification of botanical origin. Thus, cultivation under controlled growth conditions can improve the yields of active compounds and ensures production stability. Moreover, increased cultivation contributes to a reduction in the harvest pressure of wild medicinal plants, benefits the recovery of their natural habitats, and potentially stabilizes prices in the marketplace. Disadvantages of cultivation include the need for substantial investment before and during the growing and harvesting process. Another disadvantage is that cultivation often favors monocultural agriculture, which can have negative impacts on ecosystems and narrow the gene pool of what was once a wild population. Reintroduced plants can likewise cause genetic pollution of wild species, and many species cannot be successfully cultivated, even with selective breeding. Some species are, by necessity, subjected to mutational breeding, which uses exposure to chemicals or radiation to produce tetraploid plants. This method can enhance survival and disease resistance during cultivation and produce increased levels of secondary metabolites. Mutational breeding also creates a high frequency of random mutations that can increase opportunities for selective breeding purposes. Genetic engineering using techniques such as recombinant DNA to create genetically modified organisms (GMOs) is rare in Chinese medicinal herbs, although food crops are increasingly subject to this biotechnology.
- Good agricultural practices. Good agricultural practices (GAP) for medicinal plants have been formulated to regulate production, ensure quality, and facilitate the standardization of herbal drugs. A GAP approach ensures high quality, safe and pollution-free medicinal herbs by applying available knowledge to address various problems. See “Good Agricultural Collection Practices and Good Manufacturing Practices (GACP-GMP) for botanical materials” from the American Herbal Products Association and from the World Health Organization in the resource section at the end of this article. In China, this initiative is called ChinaGAP and includes cultivation, collection, and various quality aspects including authenticity of species identity, pesticide detection, macroscopic or microscopic authentication, chemical identification of bioactive compounds, and inspection of metal elements, et al. Mayway uses an agronomist consultant from Hebei Agricultural University to educate and implement ChinaGap with the growers from whom we buy our cultivated herbs. The growers of Mayway’s herbs engagement with ChinaGAP ensures that Plum Flower® herbs are the highest quality and are grown in a sustainable way that protects important medicinal herbs for use into the future.
- Organic Farming. Organic farming of medicinal plants is becoming increasingly important in the long-term development and sustainability of medicinal plants, especially in the US. Organic farming is friendly to the environment and relies upon farm-derived renewable resources to maintain biological processes of medicinal plants and ecological balance of habitats. The use of organic fertilizers and amendments continuously supplies soil nutrients and improves soil quality and stability, significantly affecting the growth of medicinal plants and the biosynthesis of essential substances.
In China, organic cultivation of medicinal plants is increasing, but relatively uncommon. Ecocert China was established in 2007 with offices in Beijing to provide China Organic Product Certification Services under the China National Organic Product Standard. In Mayway’s experience, organic herbs currently grown in China can often provide poorer yields with inconsistencies in quality that do not always meet our standards. Over time, just as has been the experience of organic farmers in the US, the expectation is that organic herbs will eventually prove to be of superior quality, rivaling wildcrafted herbs. There is a significant interest and movement for growing some Chinese herbs in the US, mostly organically. The variety of species is limited, the herbs are relatively expensive, are available in limited quantities, and, importantly, lack traditional processing. Additionally, it remains to be proven that herbs grown in North America will possess the unique factors that are thought to be derived from their growing in dào dì regions in Asia. However, this effort is quite important to the long-term sustainability of Chinese medicinal plants and to the future of traditional Chinese herbal medicine.
Despite the sustainable efforts to protect threatened species of Chinese herbs, actions have been taken by various national and international agencies to protect and limit the commercial trade of various herbs. In some cases, the restrictions listed below are implemented for sustainability reasons, in other cases, certain herbs are prohibited or controlled by safety concerns. What follows is a list of Chinese Herbs which may not be available or are restricted for sale in the US.
Restricted Herb and Resource List
CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora)
Herbs that are regulated (require an export permit) and/or prohibited (no importation allowed) https://cites.org/eng/app/appendices.php
(Current Appendices updated as of 22 June 2021)
Appendix I lists species for which no commercial trade is allowed in order to protect them from extinction. (Certain cultivated plants may be available through special permits. *)
- Bao Gu 豹骨/ Pardi Os, Panther or Leopard bone (+ any other parts)
- Chuan Shan Jia 穿山甲/Manitis Manis pentadactyl Squama, pangolin scales (Obsolete B1064†)
- Dai Mao 玳瑁/ Carapax Eretmochelydis, Hawksbill turtle shell
- Hou Zao 猴棗/ Calculus Macacae Multattae, Rhesus monkey bile stone
- Hu Gu 虎骨/Tigris Os, Tiger bone (and any other parts) (Obsolete B1071†)
- Mu Xiang 木香/Aucklandiae lappa Radix, (aka Saussurea costus or Dolomiaea costus, Family Asteraceae), Costus root (*Available only by special permit when artificially propagated for commercial purposes.)
- She Xiang 麝香/Moschus (certain species), Deer musk (also see Appendix II)
- Shi Hu 石斛/ Orchidaceae Dendrobrii Herba, Dendrobium stem (wild species only; artificially propagated hybrids are exempted * see listing under CITES App. II)
- Ta Gan 獺肝/ Lutrae Jecur (Sp. Lutrae lutra, L. Nippon), Otter liver
- Xi Niu Jiao 犀牛角/Rhinoceri Cornu, Rhino horn
- Xiang Pi 象皮 Xiang Ya 象牙/ Corium et Dens Elephantis, Elephant skin and tusk
- Xiong Dan 熊胆/Vesica Fellea Ursi (Obsolete B1065†), Bear gall bladder
- Yang Zi E 揚子鱷/ Carapax Alligatoris, Yang Zi Alligator skin
- Zhu Long Cao 豬籠草/ Herba Nepenthe (sp. = N. khasiana & N. rajah; Pitcher Plants)
* Appendix-I plants artificially propagated for commercial purposes, as well as parts and derivatives thereof, exported under the provisions of Article VII, paragraph 4, of the Convention see: https://cites.org/eng/prog/Permit_system † Bensky, D. et al., Chinese Herbal Medicine Materia Medica, 3rd Ed., Eastland Press, 2004.
Appendix II lists the species which are threatened, but for which limited trade is allowed. An export permit is issued only if the specimen was legally obtained and if the export will not be detrimental to the survival of the species. Some of these species are being farmed and are available in limited quantities. In some cases, substitute species are available.
- Bai Ji 白芨/Bletillae Rhizoma (Family Orchidaceae), Bletilla Rhizome
- Chen Xiang 沉香/Thymeleaceae Aquilaria Lignum resinatum, Aquilaria wood
- Jīng Da Ji 京大薊/Euphorbiae pekinensis Radix, Spurge root
- Gan Sui 甘遂/Euphorbia Kansui Radix, Kansui root
- Gé jiè 蛤蚧/Gekko gecko Linnaenus, Gecko
- Gou Ji 狗脊/Dicksoniaceae Cibotium barometz Rhizoma, Cibotium fern rhizome)
- Gui Ban 龜板/Testudinis Chinemys reevesii Plastrum, Fresh water turtle shell
- Hai Ma 海馬/Syngnatidae Hippocampus spp., Seahorse
- Hong Dou Shan 红豆衫/ Cortex Taxus (sp. = T. chinensis, T. sumatrana, et al.) Himalayan Yew
- Ling Yang Jiao 羚羊角/ Bovidae Saiga tatarica L. Cornu (Critically endangered in wild) Antelope horn
- Rou Cong Rong 肉蓯蓉/ Orobanchaceae Cistanche deserticola Herba, Broomrape
- Shan Ci Gu 山慈菇/Orchidaceae Cremastrae/Pleione spp. Pseudobulbus, Chinese tulip
- She Xiang 麝香/Moschus (certain species), Deer musk
- Shi Hu 石斛/ Orchidaceae Dendrobrii Herba (all standard species including D. nobile)
- Tian Ma 天麻/ Orchidaceae Gastrodia elata Bl. Rhizoma, Gastrodia rhizome
- Xi Yang Shen 西洋參/ Panax quinquefolius Radix, American ginseng (available cultivated from US & Can., only by permit)
- Zhu Long Cao 豬籠草/ Nepenthe mirabilis Herba, Pitcher plant (see species in App. I)
Contrary to some prior reports in other sources:
- The PRC Class Protections I, II, and III are enforceable only within the PRC and are irrelevant to importation or possession restrictions in the United States.
- Lu Hui 蘆薈/ Aloe, Certain species only. Aloe barbadensis & A. vera are specifically excluded from the CITES Appendices
- Ren Shen 人参/ Radix et Rhizoma Ginseng (Panax) is not listed on any CITES Appendices except for plants from the Russian Federation
- Shan Yao 山藥/ Rhizoma Dioscoreae is not listed on any CITES Appendices
- Hu Huang Lian 胡黄連/ Rhizoma Picrorhizae is not listed on any CITES Appendices. Species Picrorhiza scrophulariiflora is specifically excluded from the Appendices.
- Ba Dou 巴豆/ Croton tiglium is not listed on any CITES Appendices. Even though it is a member of the Family Euphorbiaceae, which contains 7500 species, only succulent plants of this family are subject to the provisions of the Convention.
- Mai Ma Teng 買麻藤/ Herba Gneti (sp. = Gnetum gnemon), Gnetum (aka Joint fir) is not listed on any CITES Appendices. (However, species Gnetum montanum is listed under CITES App. III)
- Ze Qi 澤漆/ Herba Euphorbiae Helioscopiae is not listed on any CITES Appendices. See note in #6 above. It is considered highly poisonous.
- Xian Ren Zhang 仙人掌/ Herba Opuntiae stems, flowers, and parts and derivatives thereof, of naturalized or artificially propagated plants of the genera Opuntia are exempted from CITES restrictions.
FDA (Food & Drug Administration)
Herbs that have been banned and/or restricted from importation:
“Poisonous” plants and substances
- Ban Mao 斑蝥/Mylabris—cantharidin toxin (Obsolete B1036†)
- Bing Lang 檳榔/Arecae Semen—carcinogenic/addictive
- Chan Su 蟾酥/Bufo Venenum—bufo-toxins, cardiac gylcosides (Obsolete B1038†)
- Da Fu Pi 大腹皮/Arecae Pericarpium—carcinogenic/addictive
- Ma Qian Zi 馬錢子/Strychni Semen—strychnine (Obsolete B1050†)
- Ying Su Ke 罌粟殼/Papveris Pericarpium—opium alkaloids/addictive (Obsolete B1047†)
Unfit for human consumption
- Can Sha 蠶砂/Bombycis Faeces—excrement
- Wu Ling Zhi 五靈脂/Trogopteri Faeces—excrement
- Ye Ming Sha 夜明砂/Verpertilionis Faeces—excrement
- Zi He Che 紫河車/Hominis Placenta—human product
Contain aristolochic acid
- Guang Fang Ji 廣防己/Aristolochia fangchi Radix—(Obsolete B1056†)
- Guan Mu Tong 關木通/Aristolochiae manshurensis Caulis—(Obsolete B1055†)
- Ma Dou Ling 馬兜鈴/Aristochiae Fructus—(Obsolete B1053†)
- Qing Mu Xiang 青木香/Aristolochiae debilis Radix
- Xi Xin 細辛/Asari Herba
Contain Ephedrine alkaloids or is a part of the Ephedra plant*
- Ma Huang 麻黃/Ephedrae Herba
- Ma Huang Gen 麻黃根/Ephedrae Radix
*In addition to the FDA restriction on the use of Ma Huang in dietary supplements, the PRC no longer issues an export license for this herb. Medical liability insurance commonly and specifically exempts this herb from liability insurance.
USDA (United States Department of Agriculture)
Restricted from importation(may be only sold in a powdered form)
- Tu Si Zi 菟絲子/Cuscuta chinensis Semen—can sprout/parasitic/noxious, invasive plant
- Bai Mao Gen 白茅根/Imperatae cylindrica Rhizoma—can sprout/noxious, invasive plant
Federal Noxious and Invasive Weeds List:
USFW (US Fish & Wildlife)
NMFS (National Marine Fisheries Service)
DFG (CA Department of Fish & Game)
Restricted and or prohibited under the 1973 US Endangered Species Act (ESA)
The USFW and the NMFS oversee the enforcement that all products derived from and containing derivatives of species listed in the 1973 ESA are prohibited from importation and interstate trade. Possession or sale of ESA listed species or products without an ESA importation permit can be prosecuted as a felony.
Ē Jiao 阿膠/Asini Corii Colla—Equus Asinus is NOT subject to the ESA, only the species Equus africanus is listed as an Endangered Species, CITES App. I). However, the demand for Ē Jiao has placed pressure on donkey populations worldwide. Mayway’s supplier, Lanzhou Foci, has established their own ranch for raising donkeys to meet their needs in a sustainable and humane way.
Endangered Species Act (1973, as amended) 16 USC CHAPTER 35
ESA List of Species (Amended)50 CFR 17.11 (30 pages)
Special status of genus Panthera
Tigers, lions, jaguars, panthers, and leopards are afforded special protection. All trade in tiger parts is illegal under CITES Appendix I and a domestic trade ban has been in place in China since 1993. Panthera tigris is also a beneficiary of the Rhinoceros and Tiger Conservation Act of 1994. In 1998, this Act was amended to prohibit the sale, importation, or exportation of products labeled or advertised as rhinoceros or tiger products, even if there were no actual parts in the product. The law states that a person shall not sell, import, or export, or attempt to sell, import, or export, any product, item, or substance intended for human consumption or application containing, or labeled or advertised as containing, any substance derived from any species of rhinoceros or tiger. USFW has extended this ruling to include any product in which any part of any animal in Genus Panthera has been used as a substitute or alternative for tiger parts. A formal petition to de-list the tiger from the 1973 ESA was denied on August 12, 2010.
Special status of abalone
Haliotis cracherodii (Black) and Haliotis sorenseni (White), two species of abalone, are listed on the Endangered Species Act and possession of any part, including the shell, of these species of abalone is a felony under US law. Chinese herbalists using and possessing Shi Jue Ming/ Haliotidis Concha must have documentation that this herb was not obtained from these species. Your herb supplier should have a Statement of Origin accompanying every lot that is imported. Standard species from the PRC Pharmacopeia 2015 are: Haliotidis diversicolor Reeve, H. discus hannai Ino, H. ovina Gmelin, H. ruber (Leach), H. asinina Linnaeus, or H. laevigata (Donovan).
Special status of seals and sea lions
Hai Gou Shen 海狗腎/ Callorhini Testes et Penis (seal penis; aka wan na qi) is a body part of an animal that is protected under the Federal Marine Mammal Protection Act (1972). Possession of this herb, even if not for sale, is a felony.
Special status of bears in California
If you have any bear parts in your dispensary, store, or clinic, it is considered prima facie evidence of your intent to sell these parts and it will be prosecuted as a felony. This includes any part of any bear including, but not limited to gall bladders, skin, bile, paws, and teeth. CA law assumes that if you are in CA and have any bear parts, then they came from poached animals within CA (even it originally came from a bear “farm” in China!). Many other states have laws protecting bears but suffer from a loophole regarding origin. Currently, there is a law before Congress to create a federal law protecting bears: H.R.2325 - Bear Protection Act of 2021. It reads in part: To conserve global bear populations by prohibiting the importation, exportation, and interstate trade of bear viscera and items, products, or substances containing, or labeled or advertised as containing, bear viscera, and for other purposes. A version of this bill is introduced yearly and has bipartisan, but not universal support in the Senate and House. It is unlikely to be passed this year.
CA Fish and Game Code (FGC) §4758
Potentially Unsafe Herbs (may be subject to detention and/or may require a permit to import)
- Ba Dou 巴豆/Crotonis Fructus—poisonous oil content
- Bing Pian 冰片/Borneolum— camphor resin
- Fu Zi 附子, Cao Wu 草烏, Wu Tuo 烏頭/ Aconitum sp. – Aconitine alkaloid content
- Gé jiè 蛤蚧/Gekko gecko Linnaenus—exotic animal ban in China (COVID), also CITES App. II
- Hu Ji Sheng 槲寄生/Visci Herba—(mistletoe) toxic lectin content
- Qian Niu Zi 牽牛子/ Ipomoea hederacea, I. nil, I. purpurea (=Pharbitis)—ergot alkaloids
- Man Tuo Luo 曼陀羅/Datura Stramontium—tropane alkaloid content
- Niu Huang 牛黃/Bovis Calculus—cow gall stone
- Qian Dan 鉛丹/Minium—lead content
- Tian Hua Fen 天花粉/Trichosanthes Radix – trichosanthin content (abortifacient)
- Tian Xian Zi 天仙子/ Hyoscyamus niger – tropane alkaloid content
Other Herbs Classified as Obsolete†
- Lei Gong Teng 雷公藤/Tripterygii Radix (Obsolete B1051†)
- Mi Tuo Seng 密陀僧/Litharge (Obsolete B1061†)
- Peng Sha 硼砂/Borax—toxic (Obsolete B1063†)
- Qing Fen 輕粉/Calomelas—very toxic (Obsolete B1058†)
- Xiong Huang 雄黄/Realgar—poisonous (As2O3) (Obsolete B1060†)
- Xun Gu Feng 尋骨風/Aristolochiae Herba—aristolochic acid (Obsolete B1057†)
- Zhu Sha 朱砂/Cinnabaris—HgS (mercuric sulfide), w/heatàHg (Obsolete B1045†)
† Obsolete Substances, Chinese Herbal Materia Medica, 3rd Edition, Bensky, Clavey, Stoger, et al., Eastland Press, 2004.
Other Herbs that Mayway USA does not carry as raw (bulk) herbs:
- An Xi Xiang 安息香/Benzoinum—resin (balsam)
- Shang Lu 商陸/Phytolaccae Radix—harsh cathartic
- Sheng Tie Luo 生鐵落/Ferri Frusta—toxic
- Su He Xiang 蘇合香/Styrax—resin (balsam)
- Yuan Hua 芫花/Gengwa Flos—harsh cathartic
- Yang Qi Shi 陽起石/Actinolitum—probable asbestos content
Parasitic plants, citrus plants, and potentially contaminated plants
These are regulated products and herbs which may be restricted or require special processing. (Otherwise, these herbs may require a special permit or may be prohibited from importation.)
- Huo Ma Ren 火麻仁/ Cannabis sativa L., seed
- Zhi Ke 枳殼, Zhi Shi 枳實/ Citrus aurantium (immature Bitter Orange), C. Kotokan, C. natsudaidai, C. wilsonii, Poncirus trifoliata, C. unshiu
- Chen Pi 陳皮, Ju He 橘核, Ju Hong 橘红,Qing Pi 青皮, Citrus reticulata, C. tangerina, C. erythrocarpa, C. grandis, C. unshiu, C. nobilis, C. leiocarpa, C. tankan, C. medica
- Yi Yi Ren 薏苡仁, Shu Yi Ren 熟薏苡/ Coix lachrymajobi
- Bai Xian Pi 白鮮皮/ Dictamnus dasycarpus
- Wu Zhu Yu 吴茱萸/ Evodia rutaecarpa
- Shi Da Gong Lao 十大功勞/ Mahonia bealei, M. fortunei, M. japonica
- Sang Bai Pi 桑白皮, Sang Shen 桑椹, Sang Ye 桑葉, Sang Zhi/ Morus alba
- Qian Li Xiang (Yué Jú) 千里香 / Murraya paniculata, Orange jasmine
- Zhu Ru 竹茹, Zhu Li 竹瀝, Tian Zhu Huang 天竺黄/ Phyllostachys nigra (Bambusaceae)
- Song Jie 松節, Song Ye 松葉/ Pinus massoniana
- Tu Jing Pi 土荆皮/ Pseudolarix amabilis
- Fu Xiao Mai 浮小麥/ Triticum aestivum
- Chuan Jiao 川椒 Hua Jiao 花椒, Chuan Jiao Mu 川椒目/ Zanthoxylum schinifolium, Z. Bungeanum, Z. Simulans, Z. Piperitum Z. nitidum
- Yu Mi Xu 玉米鬚/ Zea Mays
- Huang Bai 黃柏/ Phellodendron chinensis
Every effort has been extended to make this as accurate and as complete a document as possible. However, omissions and errors may have occurred. Mayway USA would like to keep this list correct and current. Please contact our Quality Assurance Manager Dr. Skye Sturgeon with corrections and questions.
- Bensky, D. et al., Chinese Herbal Medicine Materia Medica, 3rd Ed., Eastland Press, 2004.
- Chen et al., “Conservation and sustainable use of medicinal plants: problems, progress, and prospects” Chin Med (2016) 11:37 https://cmjournal.biomedcentral.com/articles/10.1186/s13020-016-0108-7
- Convention on International Trade in Endangered Species of Wild Fauna and Flora, https://cites.org/eng/app/appendices.php
- “Ethical, legal and sustainable trade in wild plants”, TRAFFIC, https://www.traffic.org/what-we-do/species/wild-plants/
- Fiskel, J. et al., “Framework for Sustainability Indicators at EPA”, Environmental Protection Agency 2012, https://www.epa.gov/sustainability/report-framework-sustainability-indicators-epa
- “Good Agricultural Collection Practices and Good Manufacturing Practices (GACP-GMP) for botanical materials”, American Herbal Products Association, https://ahpa.org/AHPAResources/GoodAgriculturalandCollectionPractices.aspx
- “Information Pertaining to the Sale of Wildlife Items”, California Dept. of Fish and Wildlife & US Fish and Wildlife Service, https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=55139&inline=1
- “Learn about Sustainability”, US Environmental Protection Agency, https://www.epa.gov/sustainability/learn-about-sustainability#what
- “Transforming the trade in wild plants”, The FairWild Foundation, https://www.fairwild.org/
- “WHO guidelines on good agricultural and collection practices (GACP) for medicinal plants”, World Health Organization, 2003, https://www.who.int/publications/i/item/9241546271