Question: What is the name of one of the native species of buckthorn that is also a powerful plant-based laxative?

Context paragraphs:
Barrens topminnow: The Barrens topminnow ("Fundulus julisia") is a species of freshwater fish in the Fundulidae family, which is in need of management so that it may continue to and increasingly survive in the wild.  There are many potential causes of decline of this species including the invasive western mosquitofish (Gambusia affinis) that will replace native species on a population level, wadding piscivorous birds preying on adults, and the overall restricted distribution of the species.  Managing for this species is vital for its success, but to do so there must be an understanding of the species' characteristics.  It is endemic to a small portion of Tennessee in the Elk River and the West Hickory creek of the Cumberland river drainage.  living up to only 3 years the life span of "F. julisia" is very short.  In many cases the majority of the population does not even reach that age.  Most adult males are eaten by birds because of their bright coloration during breeding season.  Current management plans are in place for the improvement of the species such as captive breeding and reintroduction, and also private management of streams and land.  Yet, more can be done to aid them in their survival efforts.  Buffer zones around streams can be created to promote the health of the stream and close observation of the introduced populations needs to be a priority.  With only three small original populations left in the wild it is important that species survive in captivity, but more so in its natural environment.

Cane toads in Australia: The cane toad in Australia is regarded as an exemplary case of a "feral species"—others being rabbits, foxes, cats, dogs and giant mimosa.  Australia's relative isolation prior to European colonisation and the industrial revolution—both of which dramatically increased traffic and importation of novel species—allowed development of a complex, interdepending system of ecology, but one which provided no natural predators for many of the species subsequently introduced.  The recent, sudden inundation of foreign species has led to severe breakdowns in Australian ecology, after overwhelming proliferation of a number of introduced species for which the continent has no efficient natural predator or parasite, and which displace native species—in some cases these species are physically destructive to habitat as well.  Cane toads have been very successful as an invasive species, having become established in more than 15 countries within the past 150 years.  In the Environment Protection and Biodiversity Conservation Act 1999, the Australian Government listed the impacts of the cane toad as a "key threatening process".

Rhamnus purshiana: Rhamnus purshiana (cascara buckthorn, cascara, bearberry, and in the Chinook Jargon, chittem and chitticum; syn.  "Frangula purshiana", "Rhamnus purshianus") is a species of buckthorn native to western North America from southern British Columbia south to central California, and eastward to northwestern Montana.

List of mammals of Alabama: The U.S. state of alabama is home to these known indigenous mammal species.  Historically, the state's indigenous species included one armadillo species, sixteen bat species, thirteen carnivore species, six insectivore species, one opossum species, four rabbit species, twenty-two rodent species, and three ungulate species.  Four of these native species have become extirpated within the state, including the American bison, cougar, elk, and the red wolf.

Polistes: Wasps of the cosmopolitan genus Polistes (the only genus in the tribe Polistini) are the most familiar of the polistine wasps, and are the most common type of paper wasp in North America.  It is also the single largest genus within the family Vespidae, with over 300 recognized species and subspecies.  Their innate preferences for nest-building sites leads them to commonly build nests on human habitation, where they can be very unwelcome; although generally not aggressive, they can be provoked into defending their nests.  All species are predatory, and they may consume large numbers of caterpillars, in which respect they are generally considered beneficial.  The European paper wasp, "Polistes dominula", was introduced into the US about 1981 and has quickly spread throughout most of the country, in most cases replacing native species within a few years.  This species is very commonly mistaken for a yellow jacket, as it is black, strongly marked with yellow, and quite different from the native North American species of "Polistes".  The cuckoo wasp, "Polistes sulcifer", is an obligate social parasite, whose only host is "P. dominula". " Polistes annularis", whose species name is Latin for "ringed", is also known for its distinctive red body color. " Polistes metricus" adults malaxate their insect prey by chewing them into a pulp, sucking out and ingesting the body fluids, then feeding the rest of the morsel to their larvae.  The most widely distributed South American wasp species, "Polistes versicolor", is particularly common in the southeastern Brazilian states.  This social wasp is commonly referred to as the yellow paper wasp due to the distinct yellow bands found on its thorax and abdomen.  "Polistes" wasps can be identified by their characteristic flight; their long legs dangle below their bodies, which are also more slender than a yellow jacket.

Coffee cherry tea: Coffee cherry tea is a herbal tea made from the dried skins of dried berries (or "cherries") of the coffee plant.  It is also known as "cascara", from the Spanish cáscara, meaning "husk".  It is different from cascara sagrada tea, a powerful plant-based laxative.

Rhamnus davurica: Rhamnus davurica is a species of flowering plant in the buckthorn family known by the common name Dahurian buckthorn.  It is native to China, North Korea, Mongolia, eastern Siberia, and Japan.  It is present in North America as an introduced species.

List of mammals of Newfoundland: This is a list of mammal species recorded in the wild in Newfoundland, the island portion of the Canadian province of Newfoundland and Labrador.  Only 14 known species (and one extinct species) are or were native to the island; this list is divided into native species and species introduced to the island since discovery by Europeans and colonization in the late 15th and early 16th centuries.

Hedgehog Street: Hedgehog Street is a UK-based conservation initiative set up by two charitable organisations, the People's Trust for Endangered Species (PTES) and the British Hedgehog Preservation Society (BHPS).  The project was established in 2011 in response to a detected decline in the hedgehog ("Erinaceus europaeus") population in Britain, where it is a native species.  Hedgehog Street is based around a website that provides volunteers with information about the ecology and behaviour of this mammal, tips on ways of managing gardens to benefit it, and resources to encourage volunteers to recruit other people to participate.  The ultimate goal of the site is to encourage people to cooperatively develop interconnected networks of gardens that are managed in a way that benefits hedgehogs, and the other native species associated with these habitats. Users (or “Hedgehog Champions”) can also log into a members area where they can upload photos and access forums.  As of December 2014 there were more than 32,000 volunteers registered through the website.

Honeysuckle: Honeysuckles ("Lonicera", ; syn.  "Caprifolium" Mill. ) are arching shrubs or twining bines in the family Caprifoliaceae, native to the Northern Hemisphere.  Approximately 180 species of honeysuckle have been identified.  About 100 of these species can be found in China and approximately 20 native species have been identified in Europe, 20 in India, and 20 in North America.  Widely known species include "Lonicera periclymenum" (honeysuckle or woodbine), "Lonicera japonica" (Japanese honeysuckle, white honeysuckle, or Chinese honeysuckle) and "Lonicera sempervirens" (coral honeysuckle, trumpet honeysuckle, or woodbine honeysuckle).  Hummingbirds are attracted to the flowers on some of these plants, especially "L. sempervirens" and "L. ciliosa" (orange honeysuckle).  Honeysuckle derives its name from the edible sweet nectar obtainable from its tubular flowers.  The name "Lonicera" stems from Adam Lonicer, a Renaissance botanist.

Supporting paragraphs: Coffee cherry tea Rhamnus purshiana
Answer: Rhamnus purshiana