Particularly the North American populations of the black-necked stilt have somewhat declined in the 20th century, mainly due to conversion of habitat for human use and pollution affecting both the birds directly as well as their food stocks. But altogether, the population is healthy and occurs over a large range. This stilt is therefore classified as a Species of Least Concern by the IUCN. The Hawaiian stilt, which on occasionally has been separated as a distinct species, is very rare however and numbers less than 2,000 individuals. Predation by the small Indian mongoose (Urva auropunctata), introduced to hunt rats, is suspected to have contributed to its decline.


Hipparchia statilinus has a wingspan of 60–68 millimetres (2.4–2.7 in).  These butterflies are rather variable, especially in the shades of brown present on the wings and in the intensity of the white bands. Usually the basic color of the upperside of the wings is dull brown in the male, lighter or ocher in the female, with a fringe on the edges. Two blind or very discreetly pupillated black eyespots are present on the forewings, while the hindwings show a very small eyespot.
The underside is marbled with ocher and dusty white bands. On the underside of each forewing there are two black eyespots ringed in yellow, the upper one with a white central spot. Between the two black eyespots there are two white spots. On the underside of the hindwings there may be a black spot near the posterior and anal margin. The caterpillars are greenish-beige with green-brownish longitudinal stripes.


Hippobroma longiflora, also called Star of Bethlehem or madamfate, is a flowering plant in the family Campanulaceae. It is the only species in the genus Hippobroma. It is endemic to the West Indies, but has become naturalized across the American tropics and Oceania.
It is notable for its concentrations of two pyridine alkaloids: lobeline and nicotine. The effects of nicotine and lobeline are quite similar, with psychoactive effects at small dosages and with unpleasant effects including vomiting, muscle paralysis, and trembling at higher dosages. For this reason, H. longiflora (and its various synonyms) is often referenced for both its toxicity and its ethnobotanical uses.
When uprooting this weed, it is important to wear gloves: the sap is an irritant which can be absorbed through the skin, and a small amount of sap in the eyes can cause blindness.


The white-throated swallow (Hirundo albigularis) is a small bird in the swallow family.  It is a common species, found in southern Africa, which has benefited from the increased nesting opportunities presented by the construction of bridges and dams.


The white-throated swallow is 14–17 cm long.  It has glossy dark blue upperparts and a bright chestnut crown. A dark blue-black breast band separates the white throat from the greyish white underparts and underwing coverts. The upper wings, underwing flight feathers and forked tail are blackish-blue, but the undertail has white patches near the feather tips. The white throat and blackish breast band are distinctions from similar Hirundo species. The outer feathers are slightly longer in the male than the female. Juveniles are duller than the adult, with shorter outer tail feathers and a browner crown.  The call is a mix of warbles and twitters.


The swallow breeds in southern Africa from Angola and Zambia southwards to the Cape in South Africa. It is mainly migratory, wintering in Angola, Zambia and southern Zaire.  This is a bird of open country and grassland, with a preference for highlands and nearby water. It is often found around man-made structures.


It feeds mainly on flying insects, which it pursues with a fast twisting flight like a barn swallow.


The white-throated swallow builds a bowl-shaped mud nest with a soft lining of grass or hair. It is usually near or over water, and is built on a ledge under an overhang on a rock face or on a man-made structure such as a building, dam wall, culvert or bridge. Uninhabited buildings are preferred to houses.  The nest may be reused for subsequent broods or in later years.
The three eggs of a typical clutch are white with brown and blue blotches, and are incubated by the female alone for 15–16 days to hatching. Both parents then feed the chicks. Fledging takes another 20–21 days, but the young birds will return to the nest to roost for a few days after the first flight. The young can swim a short distance to safety if they fall from the nest.


The welcome swallow (Hirundo neoxena) is a small  passerine bird in the swallow family.
It is a species native to Australia and nearby islands, and self-introduced into New Zealand in the middle of the twentieth century. It is very similar to the Pacific swallow with which it is often considered conspecific.
This species breeds in southern and eastern Australia in a variety of habitats, mostly in open areas, man-made clearings or urban environments, but not desert or dense forest. Eastern populations are largely migratory, wintering in northern Australia. Western birds and those in New Zealand are mainly sedentary.


The welcome swallow was first described by John Gould in The birds of Australia as a member of the genus Hirundo, but the first publication is often incorrectly given as in the Proceedings of the Zoological Society of London. Both its species name and common name refer to people welcoming its return as a herald of spring in southern parts of Australia.


The welcome swallow is a small size bird and is fast-flying. Their flying style is circular in pattern with swift darting motions. They have graceful shape and flight, moreover they often fly singly, in couples or in clusters.  The welcome swallow is metallic blue-black above, light grey below on the breast and belly, and rusty on the forehead, throat and upper breast. It has a long forked tail, with a row of white spots on the individual feathers. These birds are about 15 cm (5.9 in) long, including the outer tail feathers which are slightly shorter in the female. The welcome swallow's weight is about 9-20g. From the Gould collection in Tasmania a “natural size” male had a wing size of 11.1 cm, tail size of 7.4 cm, and a culmen of 0.7 cm. While the female has 10.9 cm wings, a 6.25 cm tail, and a culmen of 0.7 cm. The call is a mixture of twittering and soft warbling notes, and a sharp whistle in alarm. However, their call is normally quiet and does not carry very far.
Young welcome swallows are buffy white, instead of rufous, on the forehead and throat, and have shorter tail streamers.


The winter range in northern Australia overlaps with that of wintering barn swallow (Hirundo rustica), but the latter is readily separable by its blue breast band. Welcome swallows readily breed close to human habitation. Welcome swallows are commonly found on wires, posts and other perches.


Welcome swallows have a very large distributional range because they are a cross-regional species. Welcome swallows live mostly in eastern, western, southern and central Australia. The welcome swallows that live in eastern Australia move to northern Australia in winter. The welcome swallows that live in Western Australia and others that live in New Zealand are mostly not migratory. This swallow species has been observed nesting in the majority of New Zealand and its surrounding islands, Australia and some parts of Tasmania.  Currently, this species has been recorded in New Guinea, New Caledonia and other surrounding islands. The distribution of the welcome swallow also depends on seasonal change. During the winter, the welcome swallow in Australia will move towards the north which places it closer to the equator and warm weather. For the following spring, they will return to southern Australia to breed.


The welcome swallow is a self-introduced species from Australia that is believed to have flown over to New Zealand in the early 1900s. The welcome swallow is found throughout most parts of New Zealand, but it is very rare in Fiordland. The shape of New Zealand is narrow and long, which helped the birds to easily get to areas near water. They are also on Chatham and Kermadec Islands and in some instances have been seen on Campbell Island, Auckland Island and the Snares.


Although welcome swallows are more often near coastal and wetland areas, they can live in almost all types of habitat, except alpine areas and very dense forest. They have been documented in open areas such as farmlands, grasslands, partly cleared areas that are wooded, lands associated with bodies of water such as lakes or reservoirs, and along coastlines.  This species is well-adapted for urban and suburban life as well; it is even able to live in high altitude areas due to the provision of nesting materials provided by humans. During winter, welcome swallows move to a warmer habitat which can provide them enough food and safe shelter.


Once the welcome swallow reaches maturity it has a long breeding period. They have a monogamous social structure and a breeding period that lasts from August until March. The nest is an open cup of mud and grass, made by both sexes, and is attached to a structure, such as a vertical rock wall or building. It is lined with feathers and fur, and three to five eggs are laid. Two broods are often raised in a season. The nest size ranges from 5 centimetres to 13.5 centimetres. One particular study showed that the nests that were the highest tended to have a higher fledgling success rate possibly due to the inability of mammals to access the nests. Nesting sites can be a variety of areas and have been documented to be from urban and suburban areas to rural areas. Buildings, moveable boats and ferries, hollowed-out trees, caves and cliffs, mine tunnels and shafts, as well as underground water tanks have all been observed areas of nesting swallows. They build the cup-shape nests connecting to vertical rock walls or buildings to avoid sunlight. Nests on average take 8–23 days to build, and are often re-used for consecutive years of breeding. Welcome swallows often go back to their old nests for the next year to breed. They always work as a flock. When breeding, they usually work in pairs but often small loose groups to protect their nest and territory, especially against predatory birds. The number of successful broods can vary year to year; however, the maximum number of broods recorded is three. Each brood or clutch can range from two to seven eggs with an average of four. However, during the beginning of a breeding season, clutch sizes have been known to be bigger, whereas towards the end of the breeding season clutch sizes may be smaller. Eggs are generally laid in twenty-four- to forty-eight-hour intervals; however, one nest can have multiple clutches because the parent pair may abandon a nest if the clutch size is too small and then another pair will lay their eggs within that same nest. Eggs are generally 18 mm in length and 13mm in width with a pink colour and brown speckles. Male welcome swallows do not participate in the incubation of the eggs. Rather they forage while the female incubates, and when the female forages they either watch the nest for a short period or accompany the female in foraging.
The female alone incubates the eggs, which hatch after two to three weeks. The young are fed by both parents, and leave the nest after a further two to three weeks. Males have been known to remove faecal sacs after coaxing the cloaca of the young to dispose of them as well. The fledglings stay in the nest from 18 to 23 days and become completely independent around 35 days. However, they don't start breeding until 8 months to 14 months of age. Although welcome swallows are monogamous, more than just the breeding pair may take care of the young. Also, many swallows may live within the nest like during non-breeding periods where colonies will roost together in large numbers. Welcome swallows are good indicators of temperature, as the temperature drops lower, the less likely a swallow will be observed in the South. When swallows are around, the temperature usually does not drop below -2/-3 degree Celsius. Migration may occur during non-breeding seasons for larger more reliable food sources. These distances may be quite large as well during winter when food is not readily available. Individuals in this species have been known to live up to 6 years creating up to three broods a year during the breeding season.


These birds are extremely agile fliers, which feed on insects while in flight. They often fly fast and low to the ground on open fields in large circles or figure eight patterns. They will often swoop around animals or people in the open. Males and females tend to forage together during breeding season even with fledglings within the nest. Welcome swallows do show a habit of drinking water while flying, they do this by scooping water within their bills from lake and pond surfaces. This is because welcome swallows need to drink water frequently, which allows them to catch insects in the water as well. Welcome swallows can also cooperate with other birds or companions to drive the insects together. They can remember the insects’ activity routines to make foraging more efficient.


The hawk, snake, mink and wild cat are the main predators that hunt welcome swallows. Especially in Australia, snakes are the most dangerous predator for the birds. Snakes can climb trees to reach the nests and eat the eggs or young birds. According to one New Zealand study, the only time a nest failed was from disturbing the nest during the incubation period; these instances were from humans, mammals such as mustelids, and blackbirds preying upon the eggs. In swallows' excreta, there are various kinds of bacteria and parasites, which breed in the nest and cause very severe diseases; for example, histoplasmosis, encephalitis, salmonella, meningitis and toxoplasmosis. Hatchlings depend on maternal antibodies and immunity provided by the yolk sac within the egg. Although no specific parasites were found, welcome swallows are known as colonial breeders and are at a high risk for parasites, which may be a cause of lower breeding success but an increase in immune responsiveness. Another disease that not only affects the poultry business, but also the welcome swallow is fowlpox. This virus has two forms, cutaneous (mild harm) and diphtheritic (deadly); poultry is usually vaccinated for the virus, but wildlife is not.


An interesting fact from a biological view, indicated by recent studies, is that it has been found welcome swallows have slow growing wings that are not affected by food intake unless they are starving. This suggests that the welcome swallow prioritizes wing growth even when fasting for up to six hours at a time. It is also believed that the swallow accumulates fat in order to survive time periods that food may be scarce or conditions may be bad. This method allows rapid growth when conditions are good and stable growth when conditions are bad.


The wire-tailed swallow (Hirundo smithii) is a small passerine bird in the swallow family. It has two subspecies: H. s. smithii, which occurs throughout Africa, and H. s. filifera, which is found in southern and southeastern Asia. It is mainly resident, but populations in Pakistan and northern India migrate further south in winter. The genus name Hirundo is the Latin word for swallow. The species name smithii commemorates Christen Smith, a Norwegian botanist and geologist.


The wire-tailed swallow is a small swallow, measuring 18 cm (7.1 in) in length. It has bright blue upperparts, bright white underparts and a chestnut cap. Immature birds lack tail wires, and have dull brown (rather than chestnut) caps. The species is named for the very long filamentous outermost tail feathers, which trail behind like two wires. The sexes are similar in appearance, but the female has shorter "wires". Juveniles have a brown crown, back and tail. The Asian form, H. s. filifera, is larger and longer-tailed than the abundant African H. s. smithii.


The neat half-bowl nests are lined with mud collected in the swallows' beaks. They are placed on vertical surfaces near water under cliff ledges or nowadays more commonly on man-made structures such as buildings and bridges. The clutch is three to four eggs in Africa, up to five in Asia (Turner and Rose). These birds are solitary and territorial nesters, unlike many swallows, which tend to be colonial.


The wire-tailed swallow is a member of the genus Hirundo, a cosmopolitan group of "barn swallows". It has two subspecies:
H. s. smithii was first described by William Elford Leach and K. D. Koenig in 1818. Known as the African wire-tailed swallow, it is found throughout Africa.
H. s. filifera was first described by Stephens in 1826. Also known as the Asian wire-tailed swallow, it is found in southern and southeastern Asia.


Histiopteris incisa is a medium-sized fern, usually producing fronds of approximately 60–200 cm in length. Fronds are widely spaced, distinct, and slightly dimorphic with fertile lobes slightly narrower than the infertile lobes. Fertile lobes have the sori continuous, linear and exindusiate (without an indusium) but protected by reflexed leaf margins. Young fronds have a thick and whitish blue-green succulent stipe. Mature fronds are thin, long with red-brown stipes. Pinnae are pale greyish-green, almost a glaucous colour, they are paired and opposite and set at a wide angle and very lobed. The two lowermost lobes of each pinnae result in a bat's wing like appearance giving the fern its common name. This species has a robust creeping rhizome of 5-10mm width and is covered in brown or reddish scales.


Hoffmannseggia glauca is a dicot found in the legume family, Fabaceae.  Its common names include Indian rushpea, hog potato, and pig nut.
It is a California native which prefers alkaline desert flats, creosote bush communities, and disturbed areas.  It prefers elevations of less than  900 metres (3,000 ft).  Hoffmannseggia glauca is found outside California in Western Nevada, Texas, Mexico and South America.  In California H. glauca may be found in the San Joaquin Valley, Southern Coastal Ranges, and Western Transverse Ranges.


Hoffmannseggia glauca is an erect perennial herb and can measure up to 30 cm tall.  Branches are slender, growing out from the base of the plant, and have stalked glands.  The foliage is composed of compound leaves with primary and secondary leaflets.  Primary leaflets (5–20 mm) are odd-pinnate while secondary leaflets (4–6 mm) are even-pinnate.
The inflorescence measures 5–15 cm and is glandular.  Flowers are orange-red with spreading petals and are produced between the months of April and June.  The fruit that develops is 1.5–4 cm, glandular, curved, and short-stalked.  The fruit may or may not be deciduous.
The USDA indicates that Hoffmannseggia glauca is considered a noxious weed in Kansas.


The Pima, Apache, Cocopa, and Pueblo ate the tubers or bulbs raw, boiled or roasted.


Hoffmannseggia microphylla (syn. Caesalpinia virgata) is a species of flowering plant in the legume family known by the common name wand holdback. It is native to the southwestern United States and Baja California, where it grows in sandy and gravelly soils in the deserts.
This is a twiggy shrub producing many slender, wandlike, mostly naked stems up to two meters tall. The stems are hairy and green and have few leaves for most of the year. Before the leaves fall, they appear as twigs lined with pairs of small oval-shaped leaflets.
The shrub flowers in scattered raceme inflorescences of red-streaked yellow flowers which age to full red. The fruit is a sickle-shaped dehiscent legume pod up to 2.5 centimeters long. It is bumpy with glands and slightly hairy.


Hofmannophila is a genus of moths in the concealer moth family Oecophoridae. It is monotypic, with the single species Hofmannophila pseudospretella, the brown house moth, which appears to be closely related to species of the genus Borkhausenia.


Larvae have a brown head with a translucent dull white body and pale yellowish-brown legs. Because of the translucency of the body, it may change colour depending on gut content, in turn dependent on the colour of the fabrics ingested.


The pupa is yellowish brown and composed of strongly hooked setae on terminal abdominal body segments.


Mature individuals have pale ochre forewings interspersed with blackish brown patches. Each wing has a prominent discal spot and smaller blackish brown cellular spots. The hindwing is brownish grey, while the head, thorax, and abdomen dark grey-brown. Antennae are simple and threadlike. Wing span is 15 – 26 mm.


Usually up to 260 ova are laid by a female during one life cycle, either singly or in batches. Large females have been reported to lay 400 – 500 ova. Under favourable conditions, eggs hatch 10 – 20 days after being laid.
Larvae are active June – April, during which they spin silken tubes with the food they eat, leaving behind deposits of frass and silk. They require relatively high humidity for successful development to maturity, and the duration of their pupal stage is shortened by a higher ambient temperature.  Although they can enter diapause under unfavourable conditions, they are killed by severe frost. Before pupation, larvae leave their natal feeding site and may travel for 2 – 3 days before finding a new suitable place to pupate.
Adults are active May – September, although they can be found all year round in heated buildings. They are especially attracted to light and can fly all year round.
The mite species Cheyletus eruditus appears to be a significant predator of this moth.


The brown house moth is considered a serious pest in domestic and commercial settings because of the larvae's destructive feeding habits. Larvae feed on various manmade foodstuffs and household materials. These include stored cereals, dried fruit, seeds, clothes and furniture fabric, fur, and wood floor inlays. Other commodities reportedly eaten include book bindings, wine bottle corks and leather. Their destructive power is probably largely attributable to their unusual ability to degrade keratin, which is mediated by lactic acid bacteria present in their midgut. Larvae also bite through synthetic carpet fibres to construct their pupation cells, and since they rarely ingest the fibres, they are little affected by conventional moth-proofing agents. Moreover, this species is reported to be a more serious pest in Britain than elsewhere in the world.


See references in Savela (2003)
Carter DJ. 1984. Pest Lepidoptera of Europe. Dr W Junk Publishers
Hinton HE, Greenslade RM. 1943. Observations on species of Lepidoptera infesting stored products. XI. Notes on some moths found in bird guano. Entomologist 76: 182 -184.
Cox PD, Bell CH. 1981. A review of the biology of moth pests on stored products. Ministry of Agriculture, Fisheries and Food. Slough.
Woodroff GE. 1951. A life-history study of the brown house moth, Hofmannophila pseudopretella (Staint.) (Lep., Oecophoridae). Bulletin of Entomological Research 41: 529 – 553.
Emmett AM. 1979. A Field Guide to Smaller British Lepidoptera. British Entomological & Natural History Society. London.
Cornwell PB. 1971. Rising cost of damage by insect pests of fabrics in Britain. Int. Pest Control 5, September/October 1971: 22-27
Adkin R. 1932. Borkhausenia pseudospretella Stt. attacking book-bindings. Entomologist’s Monthly Magazine 68: 40 -41.
Cameron AE. 1938. Insect and other pests of 1937. Transactions of Highland Agricultural Society of Scotland 1938, reprinted,  35 pp.
Musgrave A J. 1947. Entomology and the leather industry. Progr. Leath. Sci. 1920-45, chap. 22, pp. 473-485. London, Brit. Leath. Manuf. Res. Ass.
Shannon A L, Attwood G, Hopcroft DH, Christeller JT. 2001. Characterization of lactic acid bacteria in the larval midgut of the keratinophagous lepidopteran, Hofmannophila pseudospretella. Letters in applied microbiology, 32(1): 36-41.
Ebeling W. 1975. Urban Entomology, University of California division of Agricultural Sciences, Los Angeles.


Hoheria populnea, commonly known as New Zealand mallow, lacebark or houhere, is a species of flowering plant in the family Malvaceae, endemic to New Zealand.
Hoheria populnea is found from the coast to lowland forests, and has a natural distribution from the North Cape of the North Island, to the Bay of Plenty. It can grow into a tree 12 metres tall and has broad, oval leaves, with serrated margins. The leaves are dark green, 5–12 cm long and 6 cm wide. Lacebark produces white flowers in clusters from January to March.
The bark of the plant was used in Māori traditional textiles to create ropes, hats, kits and headbands. Oral histories tell of early experiments to create felted material from the plant, similar to aute (the paper mulberry used in Polynesian textiles), however attempts were unsuccessful.


Holcus lanatus is a perennial grass. The specific epithet lanatus is Latin for 'woolly' which describes the plant's hairy texture. Common names include Yorkshire fog, tufted grass, and meadow soft grass. In North America, where it is an invasive species, names include velvet grass and common velvet grass.
In parts of northern Europe the grass is a common native species and a hardy pasture grass.


Holcus lanatus has velvety grey-green leaves. The stems are round. The bases of the stems are white with pink stripes or veins; this character has been called the "stripy pyjamas". The inflorescence is robust and often tinged purple. It produces a large amount of seed and is a rapid coloniser of disturbed ground. It prefers wetter ground; it is often seen around drainage ditches.  The ligule is 1–4 millimetres (0.039–0.157 in) long, blunt, and hairy.
This species can be distinguished from H. mollis by the beardless nodes on its culm, the absence of rhizomes, and the awn becoming hooked when dry and not projecting beyond the tips of the glumes. It has been known to hybridize with H. mollis, producing a male sterile hybrid with 2n = 21 chromosomes. Hybrids tend to resemble H. lanatus in their morphology.
It spreads vegetatively by developing new shoots and roots at its nodes. Plants form a blanket of runners on the soil surface. Semi-prostrate rosettes of shoots called 'mops' may form at the end of the runners. These mops root readily in contact with moist soil.


In a European survey of weed contamination in cereal seed in 1970, Holcus lanatus seed was found in 1% of samples. H. lanatus is an indicator of poor soil, low grazing levels, and poor drainage. It is tolerant of a range of soil pH, but grows best between 5.0 and 7.5. It exhibits climatic tolerance over a wide altitude range, but severe frosts can kill it. It does not survive trampling and puddling. It can be controlled in some European locations by increasing available potassium and phosphorus, increasing stock, and improving drainage. These remedies are not as effective in North America.


Holcus lanatus is a significant pest weed in Australia, as it is a winter-growing C₃ grass and survives droughts and hot summers as seed. It is distasteful to stock unless it is young and little other plant material is available. The flowers are wind-pollinated and usually out-crossing. The first seeds become viable 5 to 9 days after flowering and all are viable after 20 days. Seeds are shed from in summer and early autumn. One panicle has 100 to 380 seeds, with 177,000 to 240,000 seeds per plant, depending on time of emergence.


In North America, Holcus lanatus is an invasive species in native grasslands and other ecosystems. In Yosemite National Park it is one of nine priority noxious weeds to control for habitat restoration and regenerating native plant balances. It forms dense stands that can exclude other plants.
It is also established in Chile and Australia.


Holcus lanatus in its natural habitat is a food source for butterflies such as the speckled wood, the wall, and especially the small skipper. It is rarely utilized by the Essex skipper. In its native range it may occur in plant associations such as the Juncus subnodulosus–Cirsium palustre fen-meadow habitat.


CAL-IPC Invasive Plant Definitions. California Invasive Plant Council.
Hubbard, C. E. Grasses. Harmondsworth: Penguin Books. 1976. ISBN 978-0-14-013227-4
Yorkshire Fog. Garden Organic. Henry Doubleday Research Association (HDRA).
Holcus lanatus. The Nature's Calendar Survey.
Invasive Plant Management. Yosemite National Park. National Park Service. Retrieved June 20, 2013.


Holodiscus discolor, commonly known as ocean spray or oceanspray, creambush, or ironwood, is a shrub of western North America.


Holodiscus discolor is a fast-growing deciduous shrub usually from to 1.2–1.5 metres (4–5 feet) in height, and up to 2.1 m (7 ft) tall. Its alternate leaves are small, 5–9 centimetres (2–3+1⁄2 inches) long and 4–7 cm (1+1⁄2–3 in) broad, lobed, juicy green when new.
Cascading clusters of white flowers drooping from the branches give the plant its two common names. The flowers have a faint sweet, sugary scent. The bloom period is May to July.
It bears a small, hairy fruit containing one seed which is light enough to be dispersed by wind.


The plant is common in the Pacific Northwest, and throughout California in diverse habitats including California mixed evergreen forest, California oak woodlands, chaparral, Coast redwood forest, Douglas-fir forest, Yellow pine forest, Red fir forest, and Lodgepole pine forest. It is native to regions of California including the High Sierra Nevada, Northern and Southern California Coast Ranges, Klamath Mountains, Santa Cruz Mountains, Western Transverse Ranges, and the San Gabriel Mountains.
It is found in both openings and the common understory shrub in a variety of forest overstories from 300–1,300 m (980–4,270 ft) in elevation. It is found in a variety of habitats, from moist coastal forests to drier, cooler mountains of inland California. The plant is found in areas prone to wildfire, and it is often the first green shoot to spring up in an area recovering from a burn. It is commonly found in chaparral communities, a fire ecology ecosystem which evolved with burning periodically. It also may grow in areas cleared by logging.
In the California black oak woodland plant community, common understory associate species include Toxicodendron diversilobum (Western poison-oak), Heteromeles arbutifolia (toyon), and Dryopteris arguta (coastal wood fern).


It is of special value as a pollinator plant for native bees and butterflies.  It is also a larval host to Lorquin's admiral, pale tiger swallowtail, and spring azure caterpillars.


Historically, the plant has been used by Indigenous peoples for many purposes. Raw and cooked seeds were eaten, and leaves were mixed with those of other plants and boiled with small game animals. Many tribes used the wood and bark for making tools and furniture. Noted for the strength of its wood, it was often used for making digging sticks, spears, arrows, bows, harpoons and nails. The wood, like with many other plants, was often hardened with fire and was then polished using horsetail.
Comox natives use oceanspray when flowering as an indicator of the best time to dig for butter clams.


The Lummi used the flowers as an antidiarrheal and the leaves as a poultice. Several Native American tribes, such as the Stl'atl'imx, would steep the berries in boiling water to use as a treatment for diarrhea, smallpox, chickenpox and as a blood tonic.


Echinocactus texensis (also known as the horse crippler or devil's pincushion) is a cactus in the subfamily Cactoideae. It is endemic to the United States and Mexico.  It has one synonym.


Honckenya peploides, the sea sandwort (UK) or seaside sandplant (Canada), is the only species in the genus Honckenya of the flowering plant family Caryophyllaceae. Other common names include sea chickweed, sea pimpernal, sea-beach sandwort, and sea purslane. The scientific name is often spelled "Honkenya", and is named after the German botanist Gerhard August Honckeny (or Honkeny). This plant has a circumboreal distribution.
The plant is a succulent perennial growing at the edge of the sea. It has small greenish white pentamerous flowers with 10 stamens in the male flowers borne in the leaf axils. The fruit capsule opens in three valves.


Honckenya peploides is a small, subdioecious, spreading plant, forming patches on sand and shingle above the high water mark of beaches. The stem is branching and buried in the sand. The leaves grow in opposite pairs and are fleshy with membranous margins, pale yellowish-green and ovate, oblong or lanceolate, usually with pointed tips. The flowers are often dioecious and have parts in fives. They grow in the upper leaf axils and have ovate to lanceolate sepals, greenish-white petals of about the same length, and three styles. The fruit is a capsule larger than the sepals and superficially resembling a pea. In pistillate flowers the stamens are undeveloped while in staminate flowers, the capsules are poorly developed.
There are two subspecies, H. p. peploides is the nominate subspecies with ovate to lanceolate leaves and flowers growing singly in the upper leaf axils, while H. p. major is coarser, has longer, more slender leaves, and the flowers are mostly in a multi-flowered cyme.


Honckenya peploides has a circum-boreal distribution in both temperate and arctic regions. It is found in coastal regions on sand, shingle and pebbles, in northern Europe (including Britain), northern Asia and North America.


Clumps of Honckenya peploides of one sex (with either staminate or pistillate flowers) may be separated by a few metres or hundreds of metres from clumps of the other sex. Researchers in Spain studied whether these clumps exhibited different ecophysiological traits which made them better adapted to different microhabitats. They found that shoots growing near the edge of the clumps had higher photosynthetic efficiency and chlorophyll content. Growth rates between clumps of the different sexes did not differ significantly from each other, and male plants continued to have reproductive costs associated with flowering after the female plants had ceased to flower and the seeds were ripening.


Both the leaves and the seeds of H. peploides are used as food. The shoots and leaves are rich in vitamin A and vitamin C and can be used as a green leafy vegetable either raw or cooked. They can also be fermented to prepare a sauerkraut-like preserve, and in Iceland are fermented in whey to produce a drink. The seeds are small in size and time-consuming to gather; they can be ground up and added to flour or used as a garnish.


Hordeum jubatum, with common names foxtail barley, bobtail barley, squirreltail barley, and intermediate barley, is a perennial plant species in the grass family Poaceae. It occurs wild mainly in northern North America and adjacent northeastern Siberia. However, as it escaped often from gardens it can be found worldwide in areas with temperate to warm climates, and is considered a weed in many countries. The species is a polyploid and originated via hybridization of an East Asian Hordeum species with a close but extinct relative of Californian H. brachyantherum. It is grown as an ornamental plant for its attractive inflorescences and when done flowering for its infructescence.


Foxtail barley (Hordeum jubatum) propagates by seed. It is known for its ability to tolerate saline soils but is capable of productive growth on soil types ranging from loamy to clayey soils with pH's of 6.4 to 9.5. The upper limit of soil NaCl for productive growth and development is 1.0%. Foxtail barley is also adapted to a wide range of moisture regimes from dry to wet. Although this species is generally found on moist sites, it can withstand drought-like conditions. It is commonly found in lowland areas with restricted soil drainage, disturbed sites, waste areas and fields. Foxtail barley is a pioneer species or invader in disturbed areas and in areas with high salinity. It is among the first grasses to establish after disturbance and rapidly invades areas exposed by a receding water table.


Foxtail barley is a prolific seed producer, with each plant capable of producing upwards of 200 seeds. Seeds are elliptical, yellowish-brown and about a 0.25 inches (0.64 cm) long with four to eight awns. The seeds have sharp, backwards pointing barbs. Seed is dispersed by wind, machinery and animals and germinates in the cooler temperatures of the spring or fall. Seed germinating in the fall can overwinter and resume growth in early spring, giving Foxtail barley a competitive advantage over many crops. Germination is inhibited by warm temperatures and seeds require a period of darkness for germination to occur. Foxtail barley is a shallow-rooted plant with germination occurring at soil depths not greater than 3 inches (7.6 cm). The seedling of foxtail barley first appears as thin, vertical leaves covered in short, dense hairs. The leaves have prominent venation and rough margins, while auricles are absent or elemental and the membranous ligule is very short with fine hairs.


Foxtail barley is a fibrous-rooted, densely tufted grass that grows from 30–100 centimetres (12–39 in) tall and is erect or reclining at the base. The stems are erect and smooth and the leaf sheaths are split and hairy. The inflorescence of the mature plant is a dense, long-awned nodding spike with greenish or purplish colouring. The jointed rachis breaks into sharply pointed segments with three spikelets composing each segment. Only the central spikelet has one creamy coloured seed while each segment has seven awns with upward pointing barbs. These awns are up to 3 inches (7.6 cm) long and become easily attached to animals, clothing, machinery, etc. Leaf blades are slender and a greyish-green colour.


Foxtail barley is distinguished from cultivated barley (Hordeum vulgare L.) and Meadow barley (Hordeum brachyantherum) by lemma awn length. H. brachyantherum has awn lengths of 0.5 inches (1.3 cm); Foxtail barley has lengths of 0.5–3 inches (1.3–7.6 cm); and cultivated barley of 10–15 centimetres (3.9–5.9 in) in length. Once foxtail barley is established, it becomes extremely difficult to eradicate. Its extensive root systems and aggressive habit, as well as its ability to tolerate saline soils make it a resilient competitor. It is considered a weed because of this competitive ability and the dangers it poses to wildlife and livestock. While foxtail barley may be palatable for animals in early spring before it flowers, its seed heads, when dry, are very harmful to grazing animals. The awns can harm animals, as their upward-pointing barbs become easily attached and embedded in the animal's mouth and face, causing severe irritation, abscesses, and even blindness. In horses in can cause painful ulcers and excessive salivation resulting in eating difficulties.
Foxtail barley is also host to a number of viruses, and because it harbours wheat rust and blackstem rust, can indirectly affect the development of field crops. Since foxtail barley accumulates high amounts of salt in its leaves and roots, it has the potential of reducing soil salinity. Given foxtail barley's ability to withstand saline soils, it has been identified as having potential for the revegetation of saline mine spoils to reduce erosion. It has also been recommended as a species suitable for wildlife habitat rehabilitation on disturbed lands, but given its other less desirable traits, other natural grass species would be more beneficial.


Foxtail barley has been recorded as having varied uses among Native North American societies. The Chippewa and Potawatomi used the root as medicine; the Kawaiisu pounded and ate the seeds dry, or used the plant as a tool to rub the skin off yucca stalks. Jacques Rousseau noted Iroquois children placing the dried seed heads in the sleeves of others as a prank. The Ramah Navajo considered the plant poisonous and avoided it.


Hordeum pusillum, also known as little barley, is an annual grass native to most of the United States and southwestern Canada. It arrived via multiple long-distance dispersals of a southern South American species of Hordeum about one million years ago. Its closest relatives are therefore not the other North American taxa like meadow barley (Hordeum brachyantherum) or foxtail barley (Hordeum jubatum), but rather Hordeum species of the pampas of central Argentina and Uruguay. It is less closely related to the Old World domesticated barley, from which it diverged about 12 million years ago. It is diploid.


First described in 1818 by Thomas Nuttall, Hordeum pusillum, also known as little barley, is an annual flowering plant native to the majority of North America, mainly the United States and southwestern Canada. It is a member of the subfamily Pooideae in the grass family Poaceae. The plant itself is approximately 14–40 cm tall and is self-fertilizing. Leaves and spikelets are alternate. The flat, pubescent leaves can range anywhere from 2.4–12.7 cm in length and 2.0–4.5 mm wide. The sheath of little barley can be either glabrous or pubescent and wraps loosely around the stem. The inflorescence ranges between 4–8 cm long. Of the three alternating floral spikelets, only one is fertile. The plant's growth period is during the winter months, producing mature grains by April. The roots are fibrous, and the mark of a mature spikelet is when they turn a tan to brown color. The stem changes from a bluish-green color to brown as the plant matures. Its habitat is in sunny locations on dry gravely soils, rock outcrops, roadsides, railroads, waste places, in grasslands, and on marsh edges.


Little barley germinates best when exposed to light, and experiences best germination after one to two weeks of pre-chilling. Anymore than that and the viability of seeds decreases over time. After two weeks of pre-chilling, little barley seeds go into dormancy, allowing little barley to overwinter and come back year after year. Seeds germinate best at 17 and 20 degrees C. The more mature the seeds, the better they germinate.


Pollination occurs during the winter through the summer. The center spikelet is fertile whilst the lateral spikelets are male and infertile.


Little barley can suppress the growth of more desirable forage grasses. Little barley is best controlled prior to its dormancy in the fall or early spring, and can be further controlled through the use of the herbicides. Spring usage of herbicides has also been found effective at controlling the growth of little barley. Late winter or early spring treatment with Accent has been found effective. Prolonged usage of herbicides can result in higher tolerance.


Little barley is believed to have been cultivated by Native Americans due to its abundance in archaeological sites. Evidence for the earliest known cultivation in eastern North America was found at the Gast Spring site in what is today Louisa County, Iowa. Seeds were found alongside domesticated goosefoot seeds and squash or gourd rinds dating to 2,800 to 3,000 years ago. Large plots were required to produce adequate harvests due to the grain's small size. Hordeum pusillum was briefly domesticated during the Prehispanic period. Evidence suggests domestication took place in the southeastern and southwestern United States. In the southeastern and midwestern United States, however, domestication lasted through the Middle Archaic and protohistoric periods. To the Hohokam culture in Arizona, archeological evidence suggests that little barley was used for trade between other tribes whose diet did not normally included domesticated little barley.
Little barley cultivation is important in understanding pre-maize agriculture.


The small grains are edible, and this plant was part of the Eastern Agricultural Complex of cultivated plants used in the Pre-Columbian era by Native Americans. Before being displaced by agriculture based on maize, little barley may have been domesticated.


The grains would be dried, processed, and then cooked before eating. Cultivated for its edible grains, it is also classified as a cereal grain. Little barley seeds have an awn, a sharp hair-like attachment on the grain, which was then separated from the grain and possibly parched, roasted, and boiled. The seeds are nutritious and starchy. 100 grams of little barley constitutes almost 24.3 percent of carbohydrates, 22.4 percent of protein, 18 percent of calories, and 5–6 percent of fiber and fat of a recommended daily 2,000-calorie diet.


Little barley is known to be a mild allergen.


Horisme intestinata, the brown bark carpet moth, is a moth of the  family Geometridae. It is widespread throughout most of temperate North America. The habitat consists of wooded areas.
The wingspan is 21–32 mm. The pale tan forewings are marked with fine parallel lines. The PM and ST lines are deeply scalloped. The wide costal streak is almost unmarked. Adults are on wing from late May to late July and again from early September to early October.
The larvae have been recorded feeding on garden Clematis.


The witch-hazel cone gall aphid (Hormaphis hamamelidis) is a minuscule insect, a member of the aphid superfamily, whose presence on a witch-hazel plant is easily recognizable by a conical gall structure. The gall is green at first, then turns bright red.  This gall, rich in nutrients, provides both food and shelter for the female aphid. The host plant is witchhazel (Hamamelis virginiana). At lower altitudes they have a secondary host: river birch (Betula nigra), but this may be a different species.
At the start of spring, females or stem mothers crawl to leaf buds. As the leaf grows, the aphid injects it with a substance, possibly an enzyme or hormone, that causes that the galls to form around her. Once inside her gall the stem mother reproduces asexually and fills the gall with 50-70 female offspring. The second generation develops wings and disperses, repeating the process. The third generation includes both males and females. Towards the end of summer, the third generation reproduces sexually and lays eggs on the branches of the witch-hazel. The following spring the cycle begins anew. This cycle allows the aphid to increase its population dramatically in a relatively short period of time.


Hosackia gracilis, synonym Lotus formosissimus, is a species of legume native to western North America from British Columbia through Washington and Oregon to California. It was first described by George Bentham. It is known by the common names harlequin lotus and seaside bird's-foot trefoil. It grows in moist spots in the coastal mountains and down to the oceanside bluffs. It is a perennial herb growing upright or spreading to about 0.5 m in maximum length. It is lined with leaves each made up of a few oppositely arranged oval leaflets up to 2 cm long. The inflorescence is made up of several pealike flowers each 1 to 2 cm long. The flower has a bright yellow banner, or upper petal, and bright pink or white lower petals. The fruit is a legume pod 2 to 3 cm long.
It is believed that the caterpillars of the critically endangered lotis blue butterfly (syn. Lycaeides idas lotis, Lycaeides argyrognomon lotis, Plebejus anna lotis) feed on Hosackia gracilis on the Mendocino coast in damp coastal prairies.


Houstonia caerulea, commonly known as azure bluet, Quaker ladies, or bluets, is a perennial species in the family Rubiaceae. It is native to eastern Canada (Ontario to Newfoundland) and the eastern United States (Maine to Wisconsin, south to Florida and Louisiana, with scattered populations in Oklahoma). It is found in a variety of habitats such as cliffs, alpine zones, forests, meadows and shores of rivers or lakes.


Houstonia caerulea is a perennial herb that produces showy flowers approximately 1 cm across.  These flowers are four-parted with pale blue petals and a yellow center.  The foliage is a basal rosette with spatula-shaped leaves.  Stems are up to 20 cm tall with one flower per stalk.  Leaves are simple and opposite in arrangement with two leaves per node along the stem.  It thrives in moist acidic soils in shady areas, growing especially well among grasses.


Houstonia procumbens, the roundleaf bluet, is a perennial species in the family Rubiaceae. It is native to the southeastern United States: Louisiana, Mississippi, Alabama, Georgia, Florida and South Carolina. Its native habitats include disturbed sites, and moist, open, sandy areas. Flowers bloom March to October.


Houstonia purpurea (formerly Hedyotis purpurea) is a species of flowering plant in the coffee family known by the common names Venus's pride, woodland bluet, and purple bluet. It is native to the eastern United States from eastern Texas and Oklahoma east to Florida and Pennsylvania, with scattered  populations in Nebraska, Iowa, Michigan, New York State and New England.
There are three varieties of this species. The rarest, var. montana (Roan Mountain bluet) is a federally listed endangered species of the United States. It occurs only in the southern Appalachians along the border between Tennessee and North Carolina. It is named for Roan Mountain, one of a very few mountain peaks where it grows.


Houstonia pusilla (tiny bluet) is a plant in the family Rubiaceae native to the United States and common in the southeastern and central parts of the country, from Texas to Florida north to Delaware and South Dakota, plus an isolated population in Pima County, Arizona.
Houstonia pusilla is a short plant 6 inches (150 mm) or less in height with a tiny blue toned, yellow centered four lobed flower with a 0.25–0.33 inches (6.4–8.4 mm) diameter. The plant has a center rosette form and green herbaceous foliage with leaves up to 0.5 inches (13 mm) long. The leaves are opposite and each flower grows from a single branch growing from the leaf axil. This plant requires full sun and blooms in spring and early summer. It is a groundcover multiplying by self sowing and grows in mildly acidic soil where the grass is thin and moisture is adequate to support the plant. Its habitats include dry open places, rocky ledges, granite glades, and outcrops.


Houttuynia cordata, also known as fish mint, fish leaf, rainbow plant, chameleon plant, heart leaf,  fish wort, or Chinese lizard tail, is one of two species in the genus Houttuynia (the other being H. emeiensis). It is a flowering plant native to Southeast Asia. It grows in moist, shady locations. It was named after Martinus Houttuyn.


Houttuynia cordata is a herbaceous perennial plant that can grow to 0.6–1 m (2 ft 0 in – 3 ft 3 in), spreading up to 1 m (3 ft 3 in). The proximal part of the stem is trailing and produces adventitious roots, while the distal part of the stem grows vertically. The leaves are alternate, broadly heart-shaped, 4–9 cm (1+1⁄2–3+1⁄2 in) long and 3–8 cm (1–3 in) broad. Its flowers are greenish-yellow and borne on a terminal spike 2–3 cm (3⁄4–1+1⁄4 in) long with four to six large white basal bracts. It normally blooms in the summer.
It is considered an invasive plant because of its ability to regrow rhizomes from any segment of its foliage.


Houttuynia cordata grows in moist to wet soil or slightly submerged in water, as long as it is exposed partially or fully to the sun. It can become invasive in gardens and difficult to eradicate as their roots run deep and actively spread. It propagates by division.
It is usually found in one of its cultivated forms in temperate gardens. The 'Chameleon' variety (synonymous with H.cordata 'Court Jester',  'Tricolour', and 'Variegata') is slightly less vigorous than the parent species, with stubbier leaves mottled in both yellow and red. Another common variety, 'Flore Pleno', has masses of white bracts and retains the vigor of the parent species.
Houttuynia cordata has been naturalized in North America.


Houttuynia cordata was used in traditional Chinese medicine, including by Chinese scientists in an attempt to treat SARS and various other disorders, although there is no high-quality clinical research to confirm such uses are safe or effective, as of 2018. When administered via injection, H. cordata can cause severe allergic reactions.


Chemical compounds that contribute to the aroma of H. cordata include β-myrcene and 2-undecanone.


This species is a small shrub growing up to about 8 inches tall. The leaves are tiny, scale-like, and coated in woolly hairs. The yellow flowers have five petals and measure about a quarter inch wide. The plant flowers from May to July.


This shrub grows in sandy habitat such as pine barrens and dunes. It may be a coastal species, but since it is less tolerant of sea spray than other coastal plants, it is generally found on arid backdunes and not at the water's edge. The plant is associated with green sands colonized with nitrogen fixing blue-green algae, particularly in Alberta. These algae may give nutrients to the shrub, allowing it to grow in nutrient-poor sand soils.
This plant "requires periodic disturbance," however, it is "very sensitive to human impacts," such as trampling. It has narrow habitat requirements but it can be locally abundant.


Humulus japonicus, known as Japanese hop, is an ornamental plant in the family Cannabaceae. Some authorities have it as a synonym of Humulus scandens.
Originally native to East Asian countries such as China, Japan, Korea, and extending its habitat to Vietnam, it was imported to North America in the late 19th century as an ornamental. Since its arrival in North America, it has spread widely. It can be found throughout the Northeastern U.S. and eastern Canada, and considered an invasive species in North America. It also features on the list of invasive alien species of Union Concern since 2019. This means it can no longer be imported in the European Union. Additionally, it has become illegal to plant it, breed it, transport it, or bring it into the wild in all Member States.


Well-developed leaves with 5-9 lobes; abaxial surfaces of leaves pubescent, but not densely so; infructescence rarely longer than 2 cm, with bracts and bracteoles less than 1 cm long, and notable spinulose-ciliate Inflorescences: staminate inflorescences erect, 15–25 cm, flower anthers without glands; pistillate inflorescences spikes, conelike, ovoid; bracteole ovate-orbiculate, 7–10 mm, pilose, margins densely ciliate-hairy. Infructescences pendulous, green, conelike, ovoid to oblong, (1-)1.5-3(-4) cm; bracteoles without yellow glands.


Seeds germinate in early spring, but plants may continue to emerge if conditions are favorable. Seeds can be dispersed by number of agents including humans, animals, machines, and flood waters.


Humulus japonicus is native temperate parts of Asia (China, Japan, Korea, Taiwan and the Russian Far East) and the tropical environment of Vietnam and Laos, but has become an invasive species in North America since it was imported in the late 19th century.
The plant has been immensely successful in North America, and is found throughout eastern Canada and the eastern half of the United States, and considered a invasive species. In the United States Humulus japonicus has a lateral range from Nebraska/North Dakota to Maine and a vertical range from Minnesota to Georgia.
Japanese hops grow well given plentiful sunlight, moisture, and nutrient rich soil, and are most commonly found along stream banks and floodplains. Japanese hops do not grow as well in shaded areas and drier soils. In milder climates, it can survive the winter.


The plant was introduced into America in the 19th century both as an ornamental and raw ingredient for the Asian tonic. In traditional Chinese medicine this herb known as lü cao is used rather uncommonly, with supposed diuretic and heat-cooling effects.
Although related to the common hop Humulus lupulus, whose cultivars are the brewer's hop used in beer production, the Japanese hop is found to be deficient in the bitter acids and essential oils used for flavoring beer, being devoid of lupulin glands (or producing very few resin glands); hence the Japanese hop is not considered viable for use in brewing.


This species is a host plant for the butterfly Polygonia c-aureum, the Asian comma, hence in China the butterfly is considered a major pest affecting the cash crop used in medicine.


Humulus lupulus, the common hop or hops, is a species of flowering plant in the hemp family Cannabaceae, native to Europe, western Asia and North America. It is a perennial, herbaceous climbing plant which sends up new shoots in early spring and dies back to a cold-hardy rhizome in autumn. It is dioecious (having separate male and female plants).
As the female cone-shaped flowers (hops) are used to preserve and flavor beer, the species is widely cultivated by the brewing industry.


Humulus lupulus is a perennial herbaceous plant up to 10 metres (33 feet) tall, living up to 20 years. It has simple leaves with 3–5 deep lobes that can be opposite or alternate. The species is triggered by the longer summer days to flower, usually around July or August. The plant is dioecious, with male and female flowers on separate plants. The fragrant flowers are wind-pollinated. The staminate (male) flowers do not have petals, while the pistillate (female) flowers have petals enveloping the fruit. The female flower cones (or strobili) are known as hops. The fruit is an achene, meaning that it is dry and does not split open at maturity. The achene is surrounded by tepals and lupulin-secreting glands are concentrated on the fruit.
The species is sometimes described as a bine rather than a vine because it has stiff downward facing hairs that provide stability and allow it to climb.


H. lupulus contains myrcene, humulene, xanthohumol, myrcenol, linalool, tannins, and resin.
Hops are unique for containing secondary metabolites, flavonoids, oils, and polyphenols that impact the flavor of the products they are common in, such as beer. The bitter flavors in hops can be accounted for by acids composed of prenylated polyketides (a group of secondary metabolites), which highly impact the taste of hop-based products. Multiple genes have been identified as factors in the expression of taste including O-methyltransferase 1, geranyl diphosphate synthase, and chalcone synthase. Genomic analyses have shown evidence that the intervention of humans in the selection process of the hop over the thousands of years it has been cultivated have provided noticeable enhancements in aroma and bitterness as well as selection of varieties with high yield rates.


Predicted genes in homologous primary contigs have been identified as accounting for various traits expressed via variation in the growth, flowering, and stress responses in the plant. These homologous primary contigs correspond to regions with large amounts of sequence variation. Genes in the hop that contain higher rates of sequence divergence in homologous primary contigs (overlapping DNA sequences inherited by a common ancestor) have been attributed to the expression of flowering, growth and responses to (both antibiotic and biotic) stress in the plant. The responses to stress are thought to manifest in the distinct differences and difficulties in the cultivation processes between geographically popular varieties of the hop plant. Outside environmental stress, such as changes in temperature and water availability has also been shown to significantly alter the transcriptome and incite reductions in genes known to be involved in the synthesis of secondary metabolites (including bitter acids), which are organic compounds produced that do not impact development or reproduction of hops. Environmental stress has also been shown to reduce expression of the valerophenone synthase gene, which is known to be an essential genetic component in the regulation of bitter acid production. This shows that impacts of outside stress on H. lupulus likely has a direct implication of the expression of the bitter flavor that remains an essential component of the popularity of the plant.


Humulus lupulus contains xanthohumol, which is converted by large intestine bacteria into the phytoestrogen 8-prenylnaringenin, which may have a relative binding affinity to estrogen receptors  as well as potentiating effects on GABAA receptor activity
Humulus lupulus extract is antimicrobial, an activity which has been exploited in the manufacture of natural deodorant.
Spent H. lupulus extract has also been shown to have antimicrobial and anti-biofilm activities, raising the possibility this waste product of the brewing industry could be developed for medical applications.
Extracts of  the bitter alpha-acids present in H. lupulus have been shown to decrease nocturnal activity, acting as a sleep aide, in certain concentrations.
Because of the growing understanding regarding the hop's overlap in gene structures with cannabidiolic acid synthase, the precursor structure to cannabidiol, there is a gap in general understanding about potential unknown compounds and benefits in hops. As the understanding of the health benefits available in cannabidiol increases, there is a growing demand to further investigate the overlap between cannabidiolic acid synthase and H. lupulus.


The five varieties of this species (Humulus lupulus) are:
H. l. var. lupulus – Europe, western Asia
H. l. var. cordifolius – eastern Asia
H. l. var. lupuloides (syn. H. americanus) – eastern North America
H. l. var. neomexicanus – western North American.
H. l. var. pubescens – midwestern and eastern North America
Many cultivars are found in the list of hop varieties. A yellow-leafed ornamental cultivar, Humulus lupulus 'Aureus', is cultivated for garden use. It is also known as golden hop, and holds the Royal Horticultural Society's Award of Garden Merit (AGM).


The genus name Humulus is a medieval name that was at some point Latinized after being borrowed from a Germanic source exhibiting the h•m•l consonant cluster, as in Middle Low German homele.
According to Soviet Iranist V. Abaev this could be a word of Sarmatian origin which is present in the modern Ossetian language (Ossetian: Хуымæллæг) and derives from proto-Iranian hauma-arayka, an Aryan haoma.
From Sarmatian dialects this word spread across Eurasia, thus creating a group of related words in Turkic, Finno-Ugric, Slavic and Germanic languages (see Russian: хмель, Chuvash хăмла, Finnish humala, Hungarian komló, Mordovian комла, Avar хомеллег).
The specific epithet lupulus is Latin for "small wolf". The name refers to the plant's tendency to strangle other plants, mainly osiers or basket willows (Salix viminalis), like a wolf does a sheep. Hops could be seen growing over these willows so often that it was named the willow-wolf.
The English word hop is derived from the Middle Dutch word hoppe, also meaning Humulus lupulus.


The plant is native to Europe, western Asia and North America.
It grows best in the latitude range of 38°–51° in full sun with moderate amounts of rainfall.


The flowers attract butterflies, amongst other insects.


Damson hop aphid (Phorodon humuli)
Two spotted spider mite (Tetranychus urticae)
Japanese beetle (Popillia japonica)
Comma butterfly (Polygonia c-album)
Pale tussock moth (Calliteara pudibunda)
Currant pug moth (Eupithecia assimilata)
Buttoned snout moth (Hypena rostralis)
Buff ermine moth (Spilosoma lutea)


Downy mildew (Pseudoperonospora humuli)
Powdery mildew (Podosphaera macularis)


H. lupulus is first mentioned in 768 CE when King Pepin donated hops to a monastery in Paris. Cultivation was first recorded in 859 CE, in documents from a monastery in Freising, Germany.
The chemical compounds found in H. lupulus are the main components in flavoring and bittering beer. The fragrant flower cones, known as hops, impart a bitter flavor and also have aromatic and preservative qualities. Some other compounds help with creating foam in beer. Chemicals such as linalool and aldehydes contribute to the flavor of beer. The main components of bitterness in beer are iso-alpha acids, with many other compounds contributing to beer's overall bitterness. Until the Middle Ages, Myrica gale was the most common plant used for brewing beer. H. lupulus took off as a flavoring agent for beer because it contains preserving agents which prolong the viability of a brew.


H. lupulus was voted the county flower of Kent in 2002 following a poll by the wild flora conservation charity Plantlife.


Hyacinthoides hispanica (syn. Endymion hispanicus or Scilla hispanica), the Spanish bluebell, is a spring-flowering bulbous perennial native to the Iberian Peninsula. It is one of around a dozen species in the genus Hyacinthoides, others including the common bluebell (Hyacinthoides non-scripta) in northwestern Europe, and the Italian bluebell (Hyacinthoides italica) further east in the Mediterranean region.


It is distinguished from the common bluebell by its paler and larger blue flowers, which are less pendulous and not all drooping to one side like the common bluebell; plus a more erect flower stem (raceme), broader leaves, blue anthers (where the common bluebell has creamy-white ones) and little or no scent compared to the strong fragrant scent of the northern species. Like Hyacinthoides non-scripta, both pink- and white-flowered forms occur.


Hyacinthoides hispanica is native to the western part of the Iberian Peninsula (except the extreme northwest) which includes Portugal and western Spain, but has naturalized and is cultivated in many other European countries, North America and Australia.
The Spanish bluebell was introduced in the United Kingdom. Since then, it has hybridised frequently with the native common bluebell and the resulting hybrids are regarded as invasive. The resulting hybrid Hyacinthoides × massartiana and the Spanish bluebell both produce highly fertile seed but it is generally the hybrid that invades areas of the native common bluebell. This has caused the common bluebell to be viewed as a threatened species.
The Spanish bluebell is also cultivated as a garden plant, and several named cultivars exist with flowers in various shades of white, pink and blue.


Hyacinthoides non-scripta (formerly Endymion non-scriptus or Scilla non-scripta) is a bulbous perennial plant, found in Atlantic areas from north-western Spain to the British Isles, and also frequently used as a garden plant. It is known in English as the common bluebell or simply bluebell, a name which is used in Scotland to refer to the harebell, Campanula rotundifolia. In spring, H. non-scripta produces a nodding, one-sided inflorescence of 5–12 tubular, sweet-scented violet–blue flowers, with strongly recurved tepals, and 3–6 long, linear, basal leaves.
H. non-scripta is particularly associated with ancient woodland where it may dominate the understorey to produce carpets of violet–blue flowers in "bluebell woods", but also occurs in more open habitats in western regions. It is protected under UK law, and in some other parts of its range. A related species, H. hispanica has also been introduced to the British Isles and hybridises with H. non-scripta to produce intermediates known as H. × massartiana.


Hyacinthoides non-scripta was first described by Carl Linnaeus in his seminal 1753 work Species Plantarum, as a species in the genus Hyacinthus. The specific epithet non-scriptus means "unlettered" or "unmarked" and was intended to distinguish this plant from the classical hyacinth of Greek mythology. This mythical flower, which was almost certainly not the modern hyacinth, sprang up from the blood of the dying prince Hyacinthus. His lover, the god Apollo, shed tears that marked the new flower's petals with the letters "AIAI" ("alas") as a sign of his grief.
In 1803, Johann Centurius von Hoffmannsegg and Johann Heinrich Friedrich Link transferred the species to the genus Scilla, and in 1849 Christian August Friedrich Garcke transferred it to the genus Endymion (now a synonym of Hyacinthoides); it is still widely known as "Scilla non-scripta" or "Endymion non-scriptus". In 1934, Pierre Chouard transferred the species to its current placement in the genus Hyacinthoides. Scilla was the original Greek name for the sea squill, Drimia maritima; Endymion is a character from Greek mythology; Hyacinthoides means "like a hyacinth".
The type species of Hyacinthoides is H. hispanica, while that of Endymion is "Scilla nutans", described by James Edward Smith in English Botany in 1797, but now treated as a synonym of H. non-scripta. Smith had argued that nutans ("nodding") is a more fitting epithet than non-scriptus, which makes no sense once separated from Hyacinthus, but the International Code of Nomenclature for algae, fungi, and plants requires the oldest name to be used, regardless of meaning.
Common names for Hyacinthoides non-scripta include bluebell, common bluebell, English bluebell, British bluebell, wild hyacinth, wood bell, fairy flower and bell bottle. In Scotland, the term "bluebell" is used for the harebell, Campanula rotundifolia.


Hyacinthoides non-scripta forms a clade with three other species – H. hispanica, H. paivae and H. cedretorum – centred on the Iberian Peninsula. H. paivae is restricted to a small area of north-western Iberia (Galicia and neighbouring parts of Portugal), while H. cedretorum is found in mountainous areas of western North Africa (Morocco and Algeria). Within Iberia, H. non-scripta and H. hispanica are geographically separated by the Duero river. The genus also contains seven further species, mostly distributed further east in the Mediterranean Basin.


Comparison of H. non-scripta and H. hispanica
Hyacinthoides non-scripta is a perennial plant that grows from a bulb. It produces 3–6 linear leaves, all growing from the base of the plant, and each 7–16 millimetres (0.28–0.63 in) wide. An inflorescence of 5–12 (exceptionally 3–32) flowers is borne on a stem up to 500 mm (20 in) tall, which droops towards the tip; the flowers are arranged in a 1-sided nodding raceme. Each flower is 14–20 mm (0.55–0.79 in) long, with two bracts at the base, and the six tepals are strongly recurved at their tips. The tepals are violet–blue. The three stamens in the outer whorl are fused to the perianth for more than 75% of their length, and bear cream-coloured pollen. The flowers are strongly and sweetly scented. The seeds are black, and germinate on the soil surface.
The bulbs produce contractile roots; when these roots contract, they draw the bulbs down into deeper layers of the soil where there is greater moisture, reaching depths of 10–12 cm (3.9–4.7 in). This may explain the absence of H. non-scripta from some thin soils over chalk in South East England, since the bulbs are unable to penetrate into sufficiently deep soils.
H. non-scripta differs from H. hispanica, which occurs as an introduced species in the British Isles, in a number of ways. H. hispanica has paler flowers which are borne in radially symmetrical racemes; their tepals are less recurved, and are only faintly scented. The outer stamens are fused with the tepals for less than 75% of their length, and the anthers are the same colour as the tepals. These two species are thought to have diverged 8000 years ago. The two species hybridise readily to produce fertile offspring known as Hyacinthoides × massartiana; the hybrids are intermediate between the parental species, forming a spectrum of variation which connects the two.


Bluebell habitats
Hyacinthoides non-scripta is native to the western parts of Atlantic Europe, from north-western Spain and north-western Portugal, to the Netherlands and the British Isles. It is found in Belgium, Great Britain, France, Ireland, Portugal, the Netherlands and Spain, and also occurs as a naturalized species in Germany, Italy and Romania. It has also been introduced (and can be highly invasive) into various parts of North America, in both the Pacific Northwest (British Columbia, Washington and Oregon), the Great Lakes region (Ontario, New York, Ohio and Pennsylvania) and other parts of the United States (the Virginias, Kentucky and Indiana) it has been introduced as well to New Zealand.
Despite the wide distribution of H. non-scripta, it reaches its greatest densities in the British Isles, where "bluebell woods" (woodland with the understory dominated by H. non-scripta in spring) are a familiar sight. H. non-scripta is found throughout the British Isles, with the exception of the northern Outer Hebrides (Lewis and Harris), Orkney and Shetland, and it is estimated that 25%–50% of all common bluebells may be found in the British Isles.
Bluebells are a species of deciduous woodland over much of their range, flowering and leafing early before the canopy closes in late spring. They may also be found growing under bracken or Japanese knotweed, perennial plants which also form stands with a dense summer canopy. They are most successful on slightly acid soils; the same niche in alkaline conditions may be occupied by other species such as Mercurialis perennis. As a species adapted to woodlands, the young shoots are able to penetrate through a thick layer of leaf litter, and bluebells are often used as an indicator species to identify ancient woodland. Bluebells are also frequently found in hedgerows, and in the west of their range they can be found growing in open habitats, including coastal meadows. Bluebell flowers are rich in pollen and nectar, and are chiefly pollinated by bumblebees, although they are also visited by various other insects. They are a host species for the parasitic fungus Uromyces muscari, which causes bluebell rust. The ability of H. non-scripta to take up phosphorus from the soil is greatly enhanced by the presence of arbuscular mycorrhizae in its roots.


Hyacinthoides non-scripta is not protected under international law, such as CITES or the EU Habitats Directive.
In the United Kingdom, H. non-scripta is a protected species under the Wildlife and Countryside Act 1981. Landowners are prohibited from removing common bluebells on their land for sale and it is a criminal offence to remove the bulbs of wild common bluebells. This legislation was strengthened in 1998 under Schedule 8 of the Act making any trade in wild common bluebell bulbs or seeds an offence, punishable by fines of up to £5,000 per bulb. The species is not protected in the Republic of Ireland.
In France, H. non-scripta is largely confined to the northern half of the country. It is not legally protected at the national level, but it is protected in many of the départements towards the edge of its range (Corrèze, Loiret, Gironde, Lot-et-Garonne, Dordogne, Cher, Eure-et-Loir, Indre-et-Loire and Loir-et-Cher). In Wallonia, H. non-scripta is protected under Annexe VII of the Loi sur la conservation de la nature.


Bluebells are widely planted as garden plants, either among trees or in herbaceous borders. They flower at the same time as hyacinths, Narcissus and some tulips. Their ability to reproduce vegetatively, using bulb offsets and seed, means that they can spread rapidly, and may need to be controlled as weeds.
In common with other members of their genus, bluebells - particularly their bulbs - are normally considered to be toxic. Bluebells synthesise a wide range of chemicals with potential medicinal properties: they contain at least 15 biologically active compounds that may provide them with protection against insects and animals. Certain extracts – water-soluble pyrrolidine alkaloids – are similar to compounds tested for use in combating HIV and cancer. The bulbs of bluebells are used in folk medicine as a remedy for leucorrhoea, and as a diuretic or styptic, while the sap can be used as an adhesive.
The bluebell may be regarded as the United Kingdom's "favourite flower". When the wild plant charity Plantlife organised a survey in 2004 to find a favourite flower for each county in the United Kingdom, it decided to ban voters from choosing the bluebell because it had been by far the top choice in an earlier poll for the nation's favourite flower. A stylised bluebell is used as the logo for the Botanical Society of Britain and Ireland.


Hyalymenus tarsatus, the Texas bow-legged bug, is a species of broad-headed bug in the family Alydidae. It is found in Central America, North America, and South America.


Hydrangea macrophylla is a species of flowering plant in the family Hydrangeaceae, native to Japan. It is a deciduous shrub growing to 2 m (7 ft) tall by 2.5 m (8 ft) broad with large heads of pink or blue flowers in summer and autumn. Common names include bigleaf hydrangea, French hydrangea, lacecap hydrangea, mophead hydrangea, penny mac and hortensia. It is widely cultivated in many parts of the world in many climates. It is not to be confused with H. aspera 'Macrophylla'.


The term macrophylla means large- or long-leaved.  The opposite leaves can grow to 15 cm (6 in) in length. They are simple, membranous, orbicular to elliptic and acuminate. They are generally serrated.
The inflorescence of Hydrangea macrophylla is a corymb, with all flowers placed in a plane or hemisphere, or even a whole sphere in cultivated forms. Two distinct types of flowers can be identified: central, non-ornamental, pentamerous ones, and peripheral, ornamental, tetramerous ones. The latter have sterile pistils with fertile stamen. The four sepals of decorative flowers have colors ranging from pale pink to red fuchsia purple to blue. The non-decorative flowers have five small greenish sepals and five small petals. Flowering begins in early summer and lasts until early winter. The fruit is a subglobose capsule.


Hydrangea macrophylla is native to East Asia. It is reported from seaside habitats as well as mountains in Japan, from Honshu southwards. This species has naturalized in China, Korea, Siberia, New Zealand and the Americas. It is an invasive species in the Azores and Madeira archipelagos.


Hydrangea macrophylla blooms can be blue, red, pink, light purple, or dark purple. The color is affected by soil pH. An acidic soil (pH below 7) will usually produce flower color closer to blue, whereas an alkaline soil (pH above 7) will produce flowers more pink.This is caused by a color change of the flower pigments in the presence of aluminium ions which can be taken up into hyperaccumulating plants.


In climates where Hydrangea macrophylla flowers, place in a mixed shrub border or at the back of a flower bed. Its rich foliage and large size make it a wonderful background for white or light colored flowers, even tall growing perennials and annuals. In warm climates H. macrophylla is good for adding a splash of early summer color to shady areas and woodland gardens. Minimal pruning is recommended for most prolific flowering. Flowers are easily air dried and are long lasting.
While Hydrangea macrophylla is not considered a particularly difficult plant to grow, it may fail to flower. This may be due to cold winter damage to the flower buds, not getting enough sunlight, too much nitrogen fertilizer, or pruning at the wrong time of year.
H. macrophylla forms flower buds in late summer.  As a result, pruning in late summer, fall or winter could remove potential flowers.


Phyllodulcin, hydrangenol, and their 8-O-glucosides, and thunberginols A and F can be found in H. macrophylla. Thunberginol B, the dihydroisocoumarins thunberginol C, D and E, the dihydroisocoumarin glycosides thunberginol G 3'-O-glucoside and (−)-hydrangenol 4'-O-glucoside and four kaempferol and quercetin oligoglycosides can be found in Hydrangeae Dulcis Folium, the processed leaves of H. macrophylla var. thunbergii. The leaves also contain the stilbenoid hydrangeic acid.
The various colors, such as red, mauve, purple, violet and blue, in H. macrophylla are developed from one simple anthocyanin, delphinidin 3-glucoside (myrtillin), which forms complexes with metal ions called metalloanthocyanins.
Lunularic acid, lunularin, 3,4′-dihydroxystilbene and a glycoside of lunularic acid have been found in the roots of H. macrophylla.
Hydrangine is another name for the coumarin umbelliferone, and may be responsible for the possible toxicity of the plant.


Amacha is a Japanese beverage made from fermented leaves of Hydrangea macrophylla var. thunbergii.
Hydrangeae Dulcis Folium is a drug made from the fermented and dried leaves of H. macrophylla var. thunbergii with possible antiallergic and antimicrobial properties. It also has a hepatoprotective activity by suppression of D-galactosamine-induced liver injury in vitro and in vivo.
Hydrangea macrophylla is included in the Tasmanian Fire Service's list of low flammability plants, indicating that it is suitable for growing within a building protection zone.
Leaf extracts of Hydrangea macrophylla are being investigated as a possible source of new chemical compounds with antimalarial activity.  Hydrangeic acid from the leaves is being investigated as a possible anti-diabetic drug as it significantly lowered blood glucose, triglyceride, and free fatty acid levels in laboratory animals.


The two main types of  H. macrophylla cultivars  are called "mophead" and "lacecap".
Some popular hydrangea cultivars (those marked agm have gained the Royal Horticultural Society's Award of Garden Merit) include:

'All Summer Beauty'; cold-hardy, floriferous mophead
'Alpengluhen'; deep-red colored mophead
'Altona' agm; compact plant with large rose-red florets
'Ami Pasquier' agm; floriferous, wine pink to blue mophead
'Ayesha'; small, cupped, lilac-like flowers in clusters
'Bailmer' (marketed as Endless Summer) a perpetual-blooming, pink to blue mophead
'Beauté Vendômoise'; giant whitish-pink lacecap
'Blaumeise' agm; Swiss-bred "Teller" blue lacecap
'Blue Bonnet'; hardy, blue mophead
'Blue Wave'; robust light pink to light blue lacecap
'Blushing Bride'; cold-hardy, ever-blooming white mophead
'Cocktail'; bushy shrub with ovate, serrated sepals
'Europa' agm; compact, deep pink mophead
'Forever Pink'; a pink mophead
'Générale Vicomtesse de Vibraye' agm; compact, cold-hardy, French-bred pink to blue mophead
'Hamburg'; deep-colored pink to blue mophead
'Harlequin'; a picoteed pink to purple mophead
'Lady in Red'; large lacecap flowers of rose-red
'Lanarth White' agm;  white lacecap
'Lilacina'; cold-hardy, disease-resistant pink to blue lacecap
'Love You Kiss' agm; red-margined white florets, lacecap
'Madame Emile Mouillère' agm; small shrub to 1.8 m (5.9 ft), white flowers
'Marechal Foch'; old-fashioned pink to blue mophead
'Mariesii Grandiflora'; blue or pink and white lacecap
'Mariesii Lilacina' agm; mauve pink or blue lacecap
'Mariesii Perfecta'; blue, or blue and pink, lacecap
'Masja'; bushy and compact, dark pink to pink mophead
'Möwe'; rose-red and cream lacecap
'Nigra'; pink or blue mophead, black stems
'Nikko Blue'; popular, cold-hardy pink to blue mophead
'Pia'; dwarf pink to purplish-blue mophead
'Penny Mac'; cold-hardy, pink to blue mophead
'Rotschwantz’ agm; deep red and white lacecap
'Soeur Therese'; hardy, robust white mophead
'Taube'; Swiss-bred "Teller", pink to blue lacecap
'Tokyo Delight' agm; mauve-pink and white lacecap
'Twist-N-Shout'; ever-blooming, hardy pink to blue lacecap
'Veitchii' agm; blue and white lacecap
'Westfalen' agm; compact, crimson-purple mophead
'Zorro’ agm; agm bright blue lacecap


Hydrangea quercifolia, commonly known as oakleaf hydrangea or oak-leaved hydrangea, is a species of flowering plant in the family Hydrangeaceae. It is native to the southeastern United States, in woodland habitats from North Carolina west to Tennessee, and south to Florida and Louisiana. A deciduous shrub with white showy flower heads, it is grown as a garden plant, with numerous cultivars available commercially.
Its specific epithet combines the Latin words quercus ("oak"), and folium ("leaf"). However, it is not closely related to oak species (Quercus).


Hydrangea quercifolia is a coarse-textured deciduous shrub growing to 3–12 feet (0.91–3.66 m) tall with an open crown. The plant sprouts shoots from underground stolons and often grows in colonies. Young stems are covered in a felt-like light brown bark, and the larger stems have attractive cinnamon-tan-orange bark that shreds and peels in thin flakes.
The leaves are yellowish green to dark green on top and silvery-white underneath. They have three, five or seven pointed lobes and are 4–12 in (10.2–30.5 cm) long and almost as wide. They vaguely resemble larger versions of oak leaves, similar to Quercus species with lobed foliage. Plants in shade have larger leaves than those grown in sun. The leaves turn rich shades of red, bronze and purple in autumn that persist in winter accompanying the persistent dried flower-heads.


Hydrangea quercifolia flowers are borne in erect panicles 6–12 in (15.2–30.5 cm) tall and 3–5 in (7.6–12.7 cm) wide at branch tips. Flowers age in colour from creamy white, aging to pink and by autumn and winter are a dry, papery rusty-brown.
Unlike bigleaf hydrangea (Hydrangea macrophylla), flower color does not vary with soil pH.
Hydrangea quercifolia and Hydrangea paniculata are the only hydrangeas with cone-shaped flower clusters; all the others have their flowers in ball-shaped or flat-topped clusters, called umbels.


Hydrangea quercifolia is native to the south eastern United States (Alabama, Florida, Georgia (w.), Louisiana (e.), Mississippi, North Carolina, South Carolina, Tennessee), but naturalized in other parts of the US and widely cultivated elsewhere.


Hydrangea quercifolia was noted by 18th-century botanist William Bartram in his botanizing exploration from the Carolinas to the Florida panhandle in the 1770s. It was slow to enter British and American gardens. In Britain it flowers less profusely and even has a reputation for being tender.


Hydrangea quercifolia is cultivated as an ornamental plant in gardens and parks. Though frequently seen as an isolated subject in gardens, it is at its best in a natural or landscaped woodland habitat against the backdrop of larger shrubs and trees. It prefers partial to almost full shade, with morning sun and afternoon shade as optimal. It will tolerate drought, but may not flower. It prefers slightly acidic soils with a pH of 5.0–6.5. In the UK the cultivars Snowflake=‘Brido’ and Snow Queen=‘Flemygea’ have gained the Royal Horticultural Society's Award of Garden Merit.
Its hardiness is USDA Zones 5–9, with 'Snow Queen' hardy to Zone 5, while some other cultivars may not be. Propagation is via cutting or division; short sections of clustered stems with some root attached will make a small shrub in a nursery row.
Fresh or dry, the blossoms of Hydrangea quercifolia are attractive as cut flowers.


Hydrangea quercifolia was declared the official state wildflower of Alabama in 1999.


Goldenseal (Hydrastis canadensis), also called orangeroot or yellow puccoon, is a perennial herb in the buttercup family Ranunculaceae, native to North America. It may be distinguished by its thick, yellow knotted rootstock. The stem is purplish and hairy above ground and yellow below ground where it connects to the yellow rhizome. Goldenseal reproduces both clonally through the rhizome  and sexually, with clonal division more frequent than asexual reproduction. It takes between 4 and 5 years for a plant to reach sexual maturity, i.e. the point at which it produces flowers. Plants in the first stage, when the seed erupts and cotyledons emerge, 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. Finally, the third stage is reproductive, at which point flowering and fruiting occurs. This last stage takes between 4 and 5 years to develop.
A second species from Japan, previously listed as Hydrastis palmatum, is now usually classified in another genus, as Glaucidium palmatum.


Hydrastis canadensis is a herbaceous perennial growing from a horizontal, yellowish rhizome that is thick with knobby knots. The finely hairy, upright, unbranched, stems grow to 15–50 centimetres (6–19+1⁄2 inches) tall. Fertile plants have a single stem with two palmately lobed leaves. Flowering plants produce a single terminal flower with no petals and three sepals and 12 or more conspicuous white pistils; flowering occurs for a short time in spring.  Fertilized flowers grow into red, raspberry-like fruits with one or two seeds.


Goldenseal contains the isoquinoline alkaloids hydrastine, berberine, berberastine, hydrastinine, tetrahydroberberastine, canadine and canalidine. A related compound, 8-oxotetrahydrothalifendine, was identified in one study. The United States Pharmacopoeia requires goldenseal sold as a supplement to have hydrastine concentrations of at least 2% and berberine concentrations of at least 2.5%. The requirements in Europe are that hydrastine concentrations be at least 2.5% and that berberine concentrations at least 3%. The hydrastine concentrations of goldenseal plants range between 1.5% and 5%, while the berberine concentrations are usually between 0.5% and 4.5%. Goldenseal is harvested for its rhizomes because the concentrations of hydrastine and berberine in the shoots do not meet these requirements. Berberine and hydrastine act as quaternary bases and are poorly soluble in water but freely soluble in alcohol. The herb seems to have synergistic antibacterial activity over berberine in vitro, possibly as a result of efflux pump inhibitory activity.


Found in southeastern Canada and the eastern United States, the plant grows in mesic forests under deciduous trees. It is found in sheltered ravines or on talus slopes.  It seems to be intolerant of disturbances in the tree canopy and grazing. It can be found growing in association with other uncommon plants such as Jeffersonia diphylla (twinleaf) and Dicentra canadensis (squirrel corn).


According to the American Cancer Society, "Goldenseal can have toxic side effects, and high doses can cause death."
Side effects of goldenseal may include "digestive complaints, nervousness, depression, constipation, rapid heartbeat, diarrhea, stomach cramps and pain, mouth ulcers, nausea, seizures, vomiting, and central nervous system depression. High doses may cause breathing problems, paralysis, and even death. Long-term use may lead to vitamin B deficiency, hallucinations, and delirium." In addition, goldenseal may cause brain damage to newborn babies if given directly or if taken by breastfeeding or pregnant mothers, and may affect blood pressure unpredictably because it contains several compounds that have opposite effects on blood pressure.
Taking goldenseal over a long period of time can reduce absorption of B vitamins, and it is cautioned to avoid goldenseal during pregnancy and lactation, with gastrointestinal inflammation and with pro-inflammatory disorders. A 2011 study found rats fed goldenseal constantly for two years had a greater tendency to develop tumors.
Goldenseal has been found to have inhibited cytochrome P450 CYP2D6, CYP3A4 and CYP3A5 activity by approximately 40%, a statistically and clinically significant reduction. CYP2D6 is a known metabolizer of many commonly used pharmaceuticals, such as antidepressants (including all SSRIs except for fluvoxamine), neuroleptics, codeine, and Metformin.  Combining goldenseal with such medications should be done with caution and under the supervision of a doctor as it can lead to serious, perhaps fatal, toxicity. Those with a genetic deficiency in these enzymes are at particular risk.


As of 1998, only 2.4% of goldenseal plant material originated from a cultivated source rather than wild harvest, although that number was projected to rise by 15–30% over the next several years. In response to conservation concerns, research has expanded regarding the propagation success of wild plant material for commercial yield. Because goldenseal grows in patches of interconnected ramets reproducing asexually through clonal propagation, transplanting rhizome propagules into cultivated settings is possible. Seed propagation is also feasible and has advantages such as lower cost and greater genetic variability, but is considered difficult and unpredictable.
Goldenseal may be commercially cultivated through agroforestry in natural settings mirroring the plant's ecological environment, or on farms with artificial shade canopies. Another propagation method of goldenseal utilizes a controlled environment such as a greenhouse growing lab where the plant's environmental needs such as light, water and temperature are artificially simulated. Crop selection and biotechnology experimentation may be employed to increase yield and pharmacological potency. Controlled environments can greatly reduce the amount of time required to grow goldenseal to its desired harvestable state. While forest-cultivated plants double in mass every three to five years, plants can double in mass every 15 weeks in growth chambers and triple in growth when in a course soil medium. Subculturing can take place every 30 days to mass-propagate the plant.
Another option is cultivating goldenseal in new regions. An experiment conducted by Douglas et al. grew goldenseal over a six-year period in a warm, temperate environment in New Zealand. The yields were 74% higher in the sixth year of growth compared to the fourth year of growth, which is when goldenseal is normally harvested. The overall growth of the allochthonous goldenseal was comparable to that found in the United States, and the hydrastine and berberine concentrations were within the American and European standards. Cultivating goldenseal in a New Zealand environment that is similar to its home range is an option to maintain its population.


Research completed by Albrecht and McCarthy shows that when goldenseal is harvested in the fall season, it has a faster population recovery than with midsummer harvests. However, a study by Douglas et al. showed that goldenseal has the highest concentrations of hydrastine and berberine in the early summer. Their research also showed that three to five years of growth will yield the highest concentration of alkaloids in the plant.
Two experiments done by Sinclair and Catling on the effects of soil turnover, fertilization and transplanting of goldenseal show that disturbances actually benefit the growth of goldenseal. The results from the first growing season of the experiment showed that soil turnover and fertilization combined show the greatest increase in plant biomass, while the results after two growing seasons showed that this group also yielded the highest proportion of flowering plants, fruit production and seed production. Both experiments also showed that soil disturbances benefit the growth of goldenseal.


At the time of the European colonization of the Americas, goldenseal was in extensive use among certain Native American tribes of North America, both as a medicine and as a coloring material. In 1798, Benjamin Smith Barton referred to the Cherokee use of goldenseal as a cancer treatment; he called attention to its properties as a bitter tonic, and as a local wash for ophthalmia. It became a favorite of the Eclectics from the time of Constantine Raffinesque in the 1830s. Tribes also used goldenseal for digestive issues, as an eyewash, as a diuretic and as a bitter.
According to the American Cancer Society, "Available scientific evidence does not support claims that goldenseal is effective in treating cancer or other diseases." According to the National Center for Complementary and Integrative Health, "The scientific evidence does not support the use of goldenseal for any health-related purpose."
In the early 20th century, it was used as a yellow dye, astringent, and insect repellent.


Hydrocharis morsus-ranae, frogbit, is a flowering plant belonging to the genus Hydrocharis in the family Hydrocharitaceae. In North America, it is referred to as common frogbit or European frog's-bit to distinguish it from the related American frogbit (Limnobium spongia).
It is a small floating plant resembling a small water lily. It bears small, three-petalled white flowers. The floating leaves are kidney-shaped and grow in rosettes on the water surface, with the roots hanging down into the water column but not normally touching bottom. Frogbit is fast growing and spreads rapidly by stolons, surviving the winter as dormant turions which rest on the bottom, rising again to the surface in spring.
Frogbit is native to Europe and parts of Asia, but it was introduced to Canada in the 1930s and has become invasive in eastern Canada and the northeastern United States, particularly around the Great Lakes. It is considered a pest in this region as it colonises waterways and forms dense masses of vegetation on the surface, threatening native biodiversity, although in its native areas it is rarely dominant.


The little gull (Hydrocoloeus minutus or Larus minutus), is a small gull that breeds in northern Europe and across the Palearctic. The genus name Hydrocoloeus is from Ancient Greek hydro, "water", and koloios, a sort of web-footed bird. The specific minutus is Latin for "small".
It also has small colonies in parts of southern Canada. It is migratory, wintering on coasts in western Europe, the Mediterranean and (in small numbers) the northeast United States; in recent years non-breeding birds have summered in western Europe in increasing numbers and in 2016 they successfully nested for the first time in Great Britain at the Royal Society for the Protection of Birds reserve at Loch of Strathbeg reserve in Aberdeenshire. As is the case with many gulls, it has traditionally been placed in the genus Larus. It is the only member of the genus Hydrocoloeus, although it has been suggested that Ross's gull also should be included in this genus.
This species breeds colonially on freshwater marshes, making a lined nest on the ground amongst vegetation. Normally 2–6 eggs are laid.
This is the smallest gull species, with a length of 25–30 cm (10–12 in), a wingspan of 61–78 cm (24–30+1⁄2 in), and a mass of 68–162 g (2+3⁄8–5+3⁄4 oz). It is pale grey in breeding plumage with a black hood, dark underwings and often a pinkish flush on the breast. In winter, the head goes white apart from a darker cap and eye-spot. The bill is thin and black and the legs dark red. The flight on rounded wings is somewhat tern-like.
Young birds have black markings on the head and upperparts, and "W" pattern across the wings. They take three years to reach maturity.
These gulls pick food off the water surface, and will also catch insects in the air like a black tern.


Hydrocotyle ranunculoides, known commonly as floating pennywort, or floating marshpennywort, is an aquatic plant in the family Apiaceae. It is native to North and South America.