4,295 articles
Pterostylis
Pterostylis, greenhood orchids (Orchidaceae), an Australasian genus of about 315 accepted species with hooded trap-flowers pollinated by fungus gnats through sexual deception, native from Maluku to New Zealand.
Puccinellia
Puccinellia (alkali grass, saltgrass) is a Poaceae genus of about 80-120 accepted species of annual or perennial halophytic grasses of damp saline habitats, subarctic to temperate worldwide; P. tenuiflora and P. nuttalliana are studied salt-tolerance models.
Puccinia melanocephala
Puccinia melanocephala, the brown rust fungus of sugarcane (distinct from P. kuehnii orange rust), spread from Africa into the Americas in 1978 and causes 10-50% yield losses, managed mainly by resistant varieties.
Pueraria
Pueraria (kudzu vine genus) is a genus of tuberous-rooted climbing legumes in Fabaceae, tribe Phaseoleae, native to Asia and the W. Pacific; established by de Candolle in 1825, later shown polyphyletic and split into five genera including Haymondia and Toxicopueraria.
Puffed rice
Puffed rice, also called muri, murmura, khoi, kurmura, or mandakki, is rice expanded by heat and pressure into a light crisp grain, eaten as a South Asian street snack, breakfast cereal, and bhel puri base.
Pulicaria
Pulicaria (fleabane), genus of aromatic Asteraceae herbs in tribe Inuleae, published by Gaertner in 1791; about 75-100 species native from Africa and Europe to the Indian Subcontinent, used as herbal tea and traditional medicine.
Pulmonaria
Pulmonaria (lungwort) is a Boraginaceae genus of about 18 perennial species native to Europe, Siberia, and N. China, with red-to-blue aging flowers, distyly, spotted leaves, and shade-garden use.
Pulmonaria officinalis
Pulmonaria officinalis, lungwort or pulmonaire officinale, is a spotted-leaved European borage-family perennial whose flowers shift from red to blue; IUCN Least Concern, long used for lung ailments.
Pumpkin
Pumpkin: large edible fruit of Cucurbita pepo, maxima, and moschata; culinary term, not taxonomic. Domesticated in Mexico and eastern North America ~10,000 B.P.; 2025 U.S. output 1.47 billion lb, Illinois leading.
Pumpkin seed
Pumpkin seed (pepita): edible seed of Cucurbita squash, mainly Cucurbita pepo. High protein (29–36%) and fat (42–46%), rich in magnesium and phosphorus; Styrian hull-less variety pressed for oil; clinical health evidence still limited.
Punica
Punica is a two-species genus of Lythraceae: the cultivated pomegranate Punica granatum and the wild, Socotra-endemic Punica protopunica, its probable ancestor with n=7 chromosomes.
Purshia tridentata
Purshia tridentata, antelope bitterbrush, is a deciduous Rosaceae shrub native from British Columbia to the US Southwest, covering about 340 million acres, valued as mule deer and livestock browse, with Frankia nitrogen fixation and deep taproots.
Pussy willow
Pussy willow (Salix discolor, American pussy willow) is a North American willow shrub of wetlands, known for silky catkins opening before leaves in early spring; dioecious, a major early bee forage, and often confused with Eurasian Salix caprea.
Puya raimondii
Puya raimondii, commonly called the Queen of the Andes, is a giant bromeliad endemic to the high Andes of Peru and Bolivia and the largest species in the Bromeliaceae.
Pyracantha
Pyracantha (firethorn) is a genus of six accepted evergreen, thorny Rosaceae shrubs native from southern Europe to China, grown for white spring flowers and red, orange, or yellow winter berries, prone to scab and fireblight.
Pyracantha coccinea
Pyracantha coccinea, scarlet firethorn (buisson ardent), a thorny evergreen Rosaceae shrub native from southern Europe to Iran, grown for white flowers and red berries, invasive in Florida, Brazil, and South Africa.
Pyrola
Pyrola (wintergreens) is a genus of about 42 accepted evergreen herbs in Ericaceae, tribe Pyroleae, native to subarctic and temperate Northern Hemisphere to Guatemala and Sumatera; Asian origin, dust-seed mycoheterotrophy, and use as the Chinese medicine Luxiancao distinguish it.
Pyrus
Pyrus is the pear genus of Rosaceae, native to temperate Eurasia and NW Africa, with about 77 accepted species, Occidental and Oriental clades, and independently domesticated European and Asian pears.
Pyrus calleryana
Pyrus calleryana, Callery or Bradford pear, is an Asian Rosaceae tree native to China, Korea, Japan, Taiwan, and Vietnam, planted ornamentally in the US since the early 1900s and now invasive there because cultivar cross-pollination yields viable, bird-dispersed seed.
Pyrus communis
Pyrus communis, the European pear, is a Rosaceae tree native from Europe to northern Iraq, domesticated separately in Europe and the Caucasus, fifth most produced fruit worldwide, with cultivars like Bartlett and Bosc.
Pyrus pyrifolia
Pyrus pyrifolia (Burm.f.) Nakai, the Asian or nashi pear (syn. Pyrus serotina), is a Rosaceae pear tree native to southern China and Indochina, cultivated over 3,000 years; round crisp high-sugar fruit ripened on the tree, leading cultivars Chojuro, Nijisseiki, Kosui, Hosui.
Quarantine and biosecurity for conifer pests
Quarantine and biosecurity for conifer pests are the laws, inspections, surveillance, and eradication responses that stop non-native insects and pathogens from entering conifer forests through trade.
Quechua
Quechua (Salazar & L.Jost) is a monotypic Andean orchid genus in subtribe Spiranthinae, described in 2012, with the single lithophytic species Quechua glabrescens, formerly Spiranthes glabrescens, known from Ecuador and Peru.
Quercus
Quercus (oaks), genus of Fagaceae trees and shrubs with 400-450 species across the northern hemisphere, defined by acorns; fossil record from about 55 Ma, with Mexico and East Asia as diversity centers.
Quercus × hispanica
Quercus × hispanica (Lucombe oak, Fulham oak, Spanish oak) is the accepted hybrid of Quercus cerris and Quercus suber, native from SE France to NW Croatia, semi-evergreen with corky bark, described by Lamarck in 1785.
Quercus × turneri
Quercus × turneri, Turner's oak, is a semi-evergreen hybrid oak of Quercus ilex × Q. robur, raised before 1780 by Spencer Turner in Essex, described by Willdenow in 1809, with an old specimen at Kew planted 1798.
Quercus × warei
Quercus × warei, Ware's oak, is a hybrid oak (Quercus bicolor × Q. robur 'Fastigiata') published in 1998, grown as columnar landscape cultivars Regal Prince ('Long') and Kindred Spirit ('Nadler') with powdery mildew resistance and USDA zone 4-9 hardiness.
Quercus acutissima
Quercus acutissima, the sawtooth oak (Japanese kunugi), is a deciduous oak native from the Himalaya to Korea and Japan, with bristle-tipped leaf teeth and biennial acorns.
Quercus alba
Quercus alba, white oak (stave oak), a large long-lived deciduous oak of eastern North America with rounded-lobed leaves, barrel-grade wood, and declining young age classes since 1988.
Quercus cerris
Quercus cerris, Turkey oak (Saçlı Meşe), a fast-growing deciduous oak of section Cerris native to S. Europe to Türkiye and Anti-Lebanon; two-year acorns, bristly cups, drought-tolerant, IUCN least concern.