|
Pteridium
Bracken (''Pteridium'') is a genus of large, coarse ferns in the family Dennstaedtiaceae. Ferns (Pteridophyta) are vascular plants that have alternating generations, large plants that produce spores and small plants that produce sex cells (eggs and sperm). Brackens are noted for their large, highly divided leaves. They are found on all continents except Antarctica and in all environments except deserts, though their typical habitat is moorland. The genus probably has the widest distribution of any fern in the world. The word ''bracken'' is of Old Norse origin, related to Swedish ''bräken'' and Danish ''bregne'', both meaning fern. In the past, the genus was commonly treated as having only one species, ''Pteridium aquilinum'', but the recent trend is to subdivide it into about ten species. Like other ferns, brackens do not have seeds or fruits, but the immature fronds, known as ''fiddleheads'', are sometimes eaten, although some are thought to be carcinogenic. Description and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pteridium Centrali-africanum
Bracken (''Pteridium'') is a genus of large, coarse ferns in the family Dennstaedtiaceae. Ferns (Pteridophyta) are vascular plants that have alternating generations, large plants that produce spores and small plants that produce sex cells (eggs and sperm). Brackens are noted for their large, highly divided leaves. They are found on all continents except Antarctica and in all environments except deserts, though their typical habitat is moorland. The genus probably has the widest distribution of any fern in the world. The word ''bracken'' is of Old Norse origin, related to Swedish ''bräken'' and Danish ''bregne'', both meaning fern. In the past, the genus was commonly treated as having only one species, ''Pteridium aquilinum'', but the recent trend is to subdivide it into about ten species. Like other ferns, brackens do not have seeds or fruits, but the immature fronds, known as ''fiddleheads'', are sometimes eaten, although some are thought to be carcinogenic. Description and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pteridium Arachnoideum
Bracken (''Pteridium'') is a genus of large, coarse ferns in the family Dennstaedtiaceae. Ferns (Pteridophyta) are vascular plants that have alternating generations, large plants that produce spores and small plants that produce sex cells (eggs and sperm). Brackens are noted for their large, highly divided leaves. They are found on all continents except Antarctica and in all environments except deserts, though their typical habitat is moorland. The genus probably has the widest distribution of any fern in the world. The word ''bracken'' is of Old Norse origin, related to Swedish ''bräken'' and Danish ''bregne'', both meaning fern. In the past, the genus was commonly treated as having only one species, ''Pteridium aquilinum'', but the recent trend is to subdivide it into about ten species. Like other ferns, brackens do not have seeds or fruits, but the immature fronds, known as ''fiddleheads'', are sometimes eaten, although some are thought to be carcinogenic. Description and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pteridium Caudatum
Bracken (''Pteridium'') is a genus of large, coarse ferns in the family Dennstaedtiaceae. Ferns (Pteridophyta) are vascular plants that have alternating generations, large plants that produce spores and small plants that produce sex cells (eggs and sperm). Brackens are noted for their large, highly divided leaves. They are found on all continents except Antarctica and in all environments except deserts, though their typical habitat is moorland. The genus probably has the widest distribution of any fern in the world. The word ''bracken'' is of Old Norse origin, related to Swedish ''bräken'' and Danish ''bregne'', both meaning fern. In the past, the genus was commonly treated as having only one species, ''Pteridium aquilinum'', but the recent trend is to subdivide it into about ten species. Like other ferns, brackens do not have seeds or fruits, but the immature fronds, known as ''fiddleheads'', are sometimes eaten, although some are thought to be carcinogenic. Description and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pteridium Leaf Kz1
Bracken (''Pteridium'') is a genus of large, coarse ferns in the family (biology), family Dennstaedtiaceae. Ferns (Pteridophyta) are vascular plants that have alternating generations, large plants that produce spores and small plants that produce gamete, sex cells (eggs and sperm). Brackens are noted for their large, highly divided leaves. They are found on all continents except Antarctica and in all environments except deserts, though their typical habitat is moorland. The genus probably has the widest distribution of any fern in the world. The word ''bracken'' is of Old Norse origin, related to Swedish ''bräken'' and Danish ''bregne'', both meaning fern. In the past, the genus was commonly treated as having only one species, ''Pteridium aquilinum'', but the recent trend is to subdivide it into about ten species. Like other ferns, brackens do not have seeds or fruits, but the immature fronds, known as ''fiddleheads'', are sometimes eaten, although some are #Toxicity, thought ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pteridium Aquilinum
''Pteridium aquilinum'' (bracken, brake or common bracken), also known as eagle fern, is a species of fern occurring in temperate and subtropical regions in both hemispheres. Originally native to Eurasia and North America, the extreme lightness of its spores has led to it achieving a cosmopolitan distribution. Etymology Common bracken was first described as ''Pteris aquilina'' by Carl Linnaeus, in Volume 2 of his ''Species Plantarum'' in 1753. The origin of the specific epithet derived from the Latin ''aquila'' "eagle". In the reprint of the ''Flora Suecica'' in 1755, Linnaeus explains that the name refers to the image of an eagle seen in the transverse section of the root. In spite of this, the opinion has been forwarded that the name pertains to the shape of the mature fronds appearing akin to an eagle's wing. However, medieval scholars, including Erasmus, thought the pattern of the fibres seen in a transverse section of the stipe resembled a double-headed eagle or oak tree. Ta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dennstaedtiaceae
Dennstaedtiaceae is one of fifteen families in the order Polypodiales, the most derived families within monilophytes (ferns). It comprises 10 genera with ca 240 known species, including one of the world's most abundant ferns, ''Pteridium aquilinum'' (bracken). Members of the order generally have large, highly divided leaves and have either small, round intramarginal sori with cup-shaped indusia (e.g. ''Dennstaedtia'') or linear marginal sori with a false indusium formed from the reflexed leaf margin (e.g. ''Pteridium''). The morphological diversity among members of the order has confused past taxonomy, but recent molecular studies have supported the monophyly of the order and the family.Smith, A. R., K. M. Pryer, et al. (2006). "A classification for extant ferns." Taxon 55(3): 705-731 The reclassification of Dennstaedtiaceae and the rest of the monilophytes was published in 2006, so most of the available literature is not updated. Characteristics * Terrestrial or scrambling (sca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fern
A fern (Polypodiopsida or Polypodiophyta ) is a member of a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. The polypodiophytes include all living pteridophytes except the lycopods, and differ from mosses and other bryophytes by being vascular, i.e., having specialized tissues that conduct water and nutrients and in having life cycles in which the branched sporophyte is the dominant phase. Ferns have complex leaves called megaphylls, that are more complex than the microphylls of clubmosses. Most ferns are leptosporangiate ferns. They produce coiled fiddleheads that uncoil and expand into fronds. The group includes about 10,560 known extant species. Ferns are defined here in the broad sense, being all of the Polypodiopsida, comprising both the leptosporangiate (Polypodiidae) and eusporangiate ferns, the latter group including horsetails, whisk ferns, marattioid ferns, and ophioglossoid ferns. Ferns first ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fiddlehead
Fiddleheads or fiddlehead greens are the furled fronds of a young fern, harvested for use as a vegetable. Left on the plant, each fiddlehead would unroll into a new frond (circinate vernation). As fiddleheads are harvested early in the season before the frond has opened and reached its full height, they are cut fairly close to the ground. Fiddleheads contain a compound associated with bracken toxicity. The fiddlehead resembles the curled ornamentation (called a ''scroll'') on the end of a stringed instrument, such as a fiddle. It is also called a crozier, after the curved staff used by bishops, which has its origins in the shepherd's crook. Varieties The fiddleheads of certain ferns are eaten as a cooked leaf vegetable. The most popular of these are: * Bracken, ''Pteridium aquilinum'', found worldwide (Toxic if not cooked fully) * Ostrich fern, ''Matteuccia struthiopteris'', found in northern regions worldwide, and the central/eastern part of North America '' (See heal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Family (biology)
Family ( la, familia, plural ') is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between order and genus. A family may be divided into subfamilies, which are intermediate ranks between the ranks of family and genus. The official family names are Latin in origin; however, popular names are often used: for example, walnut trees and hickory trees belong to the family Juglandaceae, but that family is commonly referred to as the "walnut family". What belongs to a family—or if a described family should be recognized at all—are proposed and determined by practicing taxonomists. There are no hard rules for describing or recognizing a family, but in plants, they can be characterized on the basis of both vegetative and reproductive features of plant species. Taxonomists often take different positions about descriptions, and there may be no broad consensus across the scientific community for some time. The publishing of new data and opini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Temperateness
In geography, the temperate climates of Earth occur in the middle latitudes (23.5° to 66.5° N/S of Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ranges throughout the year and more distinct seasonal changes compared to tropical climates, where such variations are often small and usually only have precipitation changes. In temperate climates, not only do latitudinal positions influence temperature changes, but sea currents, prevailing wind direction, continentality (how large a landmass is) and altitude also shape temperate climates. The Köppen climate classification defines a climate as "temperate" C, when the mean temperature is above but below in the coldest month to account for the persistency of frost. However, other climate classifications set the minimum at . Zones and climates The north temperate zone extends from the Tropic of Cancer (approximately 23.5° north latitude) to the Arctic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus comes above species and below family (taxonomy), family. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. ''Panthera leo'' (lion) and ''Panthera onca'' (jaguar) are two species within the genus ''Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomy (biology), taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
