4,295 articles
Spinach
Spinach (Spinacia oleracea), an Amaranthaceae leafy vegetable domesticated in ancient Persia, spread to 7th-century China and Moorish Spain; dioecious cool-season crop, ~26.7 Mt production, high oxalate, downy mildew breeding.
Spinacia
Spinacia (spinach genus) is a small Amaranthaceae genus, formerly Chenopodiaceae, published by Linnaeus in 1753, native from West and Central Asia to SW Siberia; type species Spinacia oleracea, cultivated spinach.
Spiraea
Spiraea (spirea, bridal-wreaths), a Rosaceae shrub genus published by Linnaeus in 1753, native to the temperate Northern Hemisphere with about 100 accepted species, most diverse in eastern Asia; Japanese spiraea is invasive in the US.
Spiranthes
Spiranthes (ladies'-tresses) is a genus of about 44 accepted terrestrial orchid species with small white to pink flowers spirally arranged on a spike; centered in North America, dispersed to Eurasia about 7 million years ago, and prone to hybrid speciation.
Spirodela
Spirodela (giant duckweed) is a genus of four free-floating aquatic plants in Araceae, Lemnoideae, the most ancestral duckweed genus, used in wastewater phytoremediation and genomics, with Spirodela polyrhiza the type species.
Spirogyra
Spirogyra is a genus of unbranched filamentous freshwater green algae (Zygnemataceae) with spiral ribbon chloroplasts, reproducing by conjugation; 400-plus species, closest algal relatives of land plants, also called pond silk.
Splachnaceae
Splachnaceae, the dung moss family (Splachnum, Tetraplodon, Tayloria), is a moss family of about 73 species, unique among land plants for fly-dispersed sticky spores and growth on dung and carrion.
Spleenworts in rock gardens and ferneries
Spleenworts in rock gardens and ferneries is the cultivation of small evergreen Asplenium ferns, including maidenhair spleenwort and hart's-tongue, which naturally grow on cliffs and walls and thrive in alkaline crevices with sharp drainage and shade.
Split pea
Split peas are dried field pea (Pisum sativum) seeds, green or yellow, dehulled and split into cotyledons; a pulse used mainly for split pea soup, flour, and protein powder, with about 8 g protein and 8 g fiber per 100 g cooked.
Spondias
Spondias (mombins, hog plums, umbu, ambarella) is a genus of 18 Anacardiaceae fruit-tree species native to tropical America, Madagascar, and Asia, type genus of Spondioideae, cultivated for fruit and long used in traditional medicine.
Spondias dulcis
Spondias dulcis, also called ambarella, golden apple, or Polynesian plum (synonym Spondias cytherea), is an Anacardiaceae fruit tree native to E. Malesia to the Santa Cruz Islands, widely introduced across the tropics for its edible drupe.
Spondias mombin
Spondias mombin, yellow mombin, hog plum, jobo, or Brazilian cajá, is a tropical Anacardiaceae fruit tree native from Mexico to South America, with yellow edible drupes used fresh, processed, and in traditional medicine; IUCN Least Concern.
Spore and pollen abnormalities as ecological stress indicators
Malformed fossil spores and pollen grains, formed when meiosis or tetrad-stage grain separation is disrupted, permanently record environmental stress in land plants, peaking at mass extinctions.
Spore dispersal in ferns
Spore dispersal in ferns is how haploid spores travel from the parent plant to new sites, ejected by a sporangium cavitation catapult at about 10 meters per second.
Spore dormancy and germination in ferns
Spore dormancy and germination in ferns describe how released spores persist, sometimes over 50 years, until light, temperature, and moisture allow germination into a gametophyte.
Spores, elaters and dispersal cells of bryophytes
Spores, elaters and dispersal cells of bryophytes are the microscopic propagules and sterile helper cells through which mosses, liverworts, and hornworts reach new sites, mostly by wind.
Sporobolus
Sporobolus (dropseed) is a cosmopolitan genus of about 225 C4 grasses in Poaceae, Chloridoideae, defined by one-flowered awnless spikelets and seed-ejecting pericarps; includes turf, forage, and invasive weed species.
Sporobolus cryptandrus
Sporobolus cryptandrus (sand dropseed), a warm-season perennial C4 bunchgrass of Poaceae native from Canada to northern Mexico; drought resistant, fair livestock forage, used for erosion control, and an invasive transformer species in Eurasian sand grasslands.
Sporobolus diandrus
Sporobolus diandrus (Indian dropseed, 双蕊鼠尾粟), a tufted Poaceae grass native from Socotra and Arabia to tropical Asia, naturalized in the southern US and Pacific; two-stamened, a fodder grass and serious weed in India.
Sporobolus wrightii
Sporobolus wrightii (big sacaton, giant sacaton) is a tall perennial bunchgrass of Poaceae native to the southwestern U.S. and Mexico, tolerant of alkaline, saline, and flooded soils; its floodplain grasslands now cover about 5 percent of their original range.
Sporocarp (ferns)
A sporocarp is a hardened, nut-like reproductive body of aquatic ferns such as Marsilea and Azolla, enclosing spores and able to germinate after 100 years of dormancy.
Sprouting
Sprouting: germinating seeds (alfalfa, mung bean, broccoli, radish) and eating the whole young sprout. Nutrient-dense but a known foodborne illness vehicle; FDA recorded 52 sprout outbreaks, 1996-2020.
Spruce
Spruce, genus Picea, 40-50 evergreen conifer species of the Northern Hemisphere with peg-attached needles and pendant cones; includes Norway and Sitka spruce, major softwood timber trees threatened by bark beetles and drought.
Spruce cultivation and ornamental horticulture
Spruce cultivation and ornamental horticulture: growing Picea species such as Colorado blue, Norway, and white spruce as landscape, dwarf, and Christmas trees; site selection, watering, dwarf cultivar classes, and pest management.
Spruce forest ecology
Spruce forest ecology is the study of forests dominated by spruce trees (genus Picea), covering how these evergreen conifers regenerate, interact with soil fungi, and respond to climate change.
Spruce hybrids and introgression
Spruce hybrids are natural crosses between Picea species where ranges meet, producing introgression, the movement of genes between species; despite hybridization lasting at least 21,000 years, spruce species remain genetically distinct.
Spruce pests and diseases
Spruce pests and diseases are the insects, fungi, and fungus-like organisms that injure or kill spruce trees, led by the spruce beetle in North America.
Spruce Production Division
Spruce Production Division, a U.S. Army command of World War I (1917-1918) under Brig. Gen. Brice P. Disque, using about 30,000 soldiers in Pacific Northwest logging camps to produce aircraft-grade Sitka spruce, reaching 143 million board feet.
Spruce silviculture and timber
Spruce silviculture and timber covers the plantation management, harvesting, and wood utilization of spruce, chiefly Norway and Sitka spruce, used for construction timber, pulp, and tonewood.
Stachys
Stachys (woundwort) is a large cosmopolitan genus of Lamiaceae herbs, about 300-450 species centered in the Mediterranean and Turkey, with two-lipped flowers, debated Betonica taxonomy, and medicinal herbal-tea uses.