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Curly-leaf Pondweed
''Potamogeton crispus'', the crisp-leaved pondweed, curly pondweed, curly-leaf pondweed or curled pondweed, is a species of aquatic plant (hydrophyte) native to Eurasia but an introduced species and often a noxious weed in North America. Description Curly-leaf pondweed is a rhizomatous perennial herb producing a flattened, branching stem up to a meter long. The submerged leaves are alternately arranged. The leaves are sessile, linear or oblong in shape, long and wide. The leaves may be bright green, olive green or (especially later in the season) fibrous and brownish and have noticeably serrated margins, a feature that distinguishes them from other pondweeds. The leaves usually have wavy edges but this is not always apparent, especially on new growth. Turions occur in leaf axils and at stem tips. The inflorescence is a short spike of flowers emerging above the water surface. It flowers from May until October. The turions of the plant develop along with the fruits and germin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carl Linnaeus
Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, the modern system of naming organisms. He is known as the "father of modern taxonomy". Many of his writings were in Latin; his name is rendered in Latin as and, after his 1761 ennoblement, as . Linnaeus was born in Råshult, the countryside of Småland, in southern Sweden. He received most of his higher education at Uppsala University and began giving lectures in botany there in 1730. He lived abroad between 1735 and 1738, where he studied and also published the first edition of his ' in the Netherlands. He then returned to Sweden where he became professor of medicine and botany at Uppsala. In the 1740s, he was sent on several journeys through Sweden to find and classify plants and animals. In the 1750s and 1760s, he continued to collect an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germination
Germination is the process by which an organism grows from a seed or spore. The term is applied to the sprouting of a seedling from a seed of an angiosperm or gymnosperm, the growth of a sporeling from a spore, such as the spores of fungi, ferns, bacteria, and the growth of the pollen tube from the pollen grain of a seed plant. Seed plants Germination is usually the growth of a plant contained within a seed; it results in the formation of the seedling. It is also the process of reactivation of metabolic machinery of the seed resulting in the emergence of radicle and plumule. The seed of a vascular plant is a small package produced in a fruit or cone after the union of male and female reproductive cells. All fully developed seeds contain an embryo and, in most plant species some store of food reserves, wrapped in a seed coat. Some plants produce varying numbers of seeds that lack embryos; these are empty seeds which never germinate. Dormant seeds are viable seeds that do ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States National Agricultural Library
The United States National Agricultural Library (NAL) is one of the world's largest agricultural research libraries, and serves as a national library of the United States and as the library of the United States Department of Agriculture. Located in Beltsville, Maryland, it is one of five national libraries of the United States (along with the Library of Congress, the National Library of Medicine, the National Transportation Library, and the National Library of Education). It is also the coordinator for the Agriculture Network Information Center (AgNIC), a national network of state land-grant institutions and coordinator for the U.S. Department of Agriculture (USDA) field libraries. NAL was established on May 15, 1862, by the signing of the Organic Act by Abraham Lincoln. It served as a departmental library until 1962, when the Secretary of Agriculture officially designated it as the National Agricultural Library. The first librarian, appointed in 1867, was Aaron B. Grosh, one ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Great Lakes
The Great Lakes, also called the Great Lakes of North America, are a series of large interconnected freshwater lakes in the mid-east region of North America that connect to the Atlantic Ocean via the Saint Lawrence River. There are five lakes, which are Lake Superior, Superior, Lake Michigan, Michigan, Lake Huron, Huron, Lake Erie, Erie, and Lake Ontario, Ontario and are in general on or near the Canada–United States border. Hydrologically, lakes Lake Michigan–Huron, Michigan and Huron are a single body joined at the Straits of Mackinac. The Great Lakes Waterway enables modern travel and shipping by water among the lakes. The Great Lakes are the largest group of freshwater lakes on Earth by total area and are second-largest by total volume, containing 21% of the world's surface fresh water by volume. The total surface is , and the total volume (measured at the low water datum) is , slightly less than the volume of Lake Baikal (, 22–23% of the world's surface fresh water ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potamogeton Crispus Dorset
''Potamogeton'' is a genus of aquatic, mostly freshwater, plants of the family Potamogetonaceae. Most are known by the common name pondweed, although many unrelated plants may be called pondweed, such as Canadian pondweed (''Elodea canadensis''). The genus name means "river neighbor", originating from the Greek ''potamos'' (river) and ''geiton'' (neighbor). Morphology ''Potamogeton'' species range from large (stems of 6 m or more) to very small (less than 10 cm). Height is strongly influenced by environmental conditions, particularly water depth. All species are technically perennial, but some species disintegrate in autumn to a large number of asexually produced resting buds called turions, which serve both as a means of overwintering and dispersal. Turions may be borne on the rhizome, on the stem, or on stolons from the rhizome. Most species, however, persist by perennial creeping rhizomes. In some cases the turions are the only means to differentiate species. The leav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potamogeton Praelongus
''Potamogeton praelongus'', commonly known as whitestem pondweed in North America and long-stalked pondweed in Britain, is a large, perennial aquatic plant in the family Potamogetonaceae. It is widely distributed in lakes and rivers in the northern hemisphere, but is sensitive to poor water quality. Description Long-stalked pondweed has tall stems to 3 m growing from stout, rusty-spotted perennial rhizomes. The stems often change direction between each node, giving a characteristic zig-zagging pattern. The transparent pale to deep green leaves are typically between 60 and 150 mm long but occasionally reach 250 mm and are 14–40 mm wide. The stipules are persistent, open, whitish and translucent, with prominent veins when dry. Floating leaves and Turion (botany), turions are absent. The inflorescences are produced quite early for a pondweed, in May–June, and have 15-20 inconspicuous greenish flowers and held on robust Peduncle (botany), peduncles 80–200 m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potamogeton Lucens
''Potamogeton'' is a genus of aquatic, mostly freshwater, plants of the family Potamogetonaceae. Most are known by the common name pondweed, although many unrelated plants may be called pondweed, such as Canadian pondweed (''Elodea canadensis''). The genus name means "river neighbor", originating from the Greek ''potamos'' (river) and ''geiton'' (neighbor). Morphology ''Potamogeton'' species range from large (stems of 6 m or more) to very small (less than 10 cm). Height is strongly influenced by environmental conditions, particularly water depth. All species are technically perennial, but some species disintegrate in autumn to a large number of asexually produced resting buds called turions, which serve both as a means of overwintering and dispersal. Turions may be borne on the rhizome, on the stem, or on stolons from the rhizome. Most species, however, persist by perennial creeping rhizomes. In some cases the turions are the only means to differentiate species. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potamogeton Alpinus
''Potamogeton alpinus'' is a species of perennial aquatic plant known by the common names alpine pondweed and red pondweed. It is widespread in the northern hemisphere in both rivers and lakes with good water quality. Description Red pondweed is a perennial herb anchoring in the mud substrate via a creeping rhizome. It produces a cylindrical unbranched stem, up to 2.8 m in length. It has sessile lance-shaped submerged leaves that are typically 70–180 mm long and 10–25 mm wide with 4-7 lateral veins on either side and a slightly hooded apex, with an untoothed margin. Floating leaves may also be produced. The inflorescence is a spike of flowers a few centimeters long rising above the water surface. Turion (botany), Turions are absent, but in winter each stem dies back to a resting bud with a short length of root, which acts as a functional turion. Red pondweed is a reasonably distinctive plant and is not likely to be confused with any other pondweed. Early in the gr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potamogeton Perfoliatus
''Potamogeton perfoliatus'' (claspingleaf pondweed, perfoliate pondweed, redhead grass) is a perennial aquatic plant in the family Potamogetonaceae occurring in both standing and flowing freshwater habitats. It is widely distributed globally, occurring in all continents except South America and Antarctica. Description Perfoliate pondweed grows from a robust creeping perennial rhizome, intermittently producing round stems up to 3 m long. The submerged leaves are oval and translucent, with no stalk, 20–115 mm long and 7–42 mm wide, clasping the stem (perfoliate), a flat apex, and 5-12 veins on either side of the midrib. They vary considerably in colour and may be bright green, dark green, yellowish, olive or brownish. There are no floating leaves. The stipules are rather delicate and usually fall off quite soon after the new leaf has unfurled. The insignificant flowers are produced between June and September. Fruits are 4 mm across, olive green in colour. Two s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potamogeton Trichoides
''Potamogeton trichoides'' is a species of aquatic plant known by the common name hairlike pondweed, native to Europe and western Asia where it grows in calcareous, usually nutrient-rich standing or slow-flowing water. Description Hairlike pondweed is an aquatic perennial that dies back each winter into a large number of asexually produced resting bodies called Turion (botany), turions. There are no rhizomes. It produces slender, cylindrical or slightly compressed, branching stems usually less than a metre in length but occasionally up to 2 m. The submerged leaves are long and very narrow, typically 16–80 mm long and 0.3–1 mm wide, with the midrib occupying up to 70% of the width of the leaf near the base. They are rigid and green turning darker with age. There are no floating leaves. The inflorescence is a short spike of 3–5 flowers arising from the water on a slender Peduncle (botany), peduncle. This species readily Hybrid (biology), hybridizes with several ot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Overwintering
Overwintering is the process by which some organisms pass through or wait out the winter season, or pass through that period of the year when "winter" conditions (cold or sub-zero temperatures, ice, snow, limited food supplies) make normal activity or even survival difficult or near impossible. In some cases "winter" is characterized not necessarily by cold but by dry conditions; passing through such periods could likewise be called overwintering. Hibernation and migration are the two major ways in which overwintering is accomplished. Animals may also go into a state of reduced physiological activity known as torpor. Overwintering occurs in several classes of lifeform. Insects In entomology, overwintering is how an insect passes the winter season. Many insects overwinter as adults, pupae, or eggs. This can be done inside buildings, under tree bark, or beneath fallen leaves or other plant matter on the ground, among other places. All such overwintering sites shield the insect fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potamogeton Crispus Turion
''Potamogeton'' is a genus of aquatic, mostly freshwater, plants of the family Potamogetonaceae. Most are known by the common name pondweed, although many unrelated plants may be called pondweed, such as Canadian pondweed (''Elodea canadensis''). The genus name means "river neighbor", originating from the Greek ''potamos'' (river) and ''geiton'' (neighbor). Morphology ''Potamogeton'' species range from large (stems of 6 m or more) to very small (less than 10 cm). Height is strongly influenced by environmental conditions, particularly water depth. All species are technically perennial, but some species disintegrate in autumn to a large number of asexually produced resting buds called turions, which serve both as a means of overwintering and dispersal. Turions may be borne on the rhizome, on the stem, or on stolons from the rhizome. Most species, however, persist by perennial creeping rhizomes. In some cases the turions are the only means to differentiate species. The leav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
