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Celtis Tenuifolia
''Celtis tenuifolia'', the dwarf hackberry or Georgia hackberry is a shrub or small tree . It is native to eastern North America but is very uncommon north of the Ohio River. In Canada, dwarf hackberry is designated as threatened and protected under Canada's Species at Risk Act. Characteristics The leaves are alternate, simple, blades 5 to 7 centimeters long, and 2 to 3.5 centimeters in width, shallowly toothed, and finely hairy. The winter buds are brown and hairy, similar to those of other hackberries, but smaller, only 1 to 2 mm. long. Terminal buds absent. Flowers are monecious and unisexual, occurring either solitarily or in small clusters. This species is wind-pollinated and appears to be self-compatible. The fruit is a berry-like drupe, 5 to 8 millimeters in diameter, consisting of a single stone encased within a thin, sweet mesocarp. From green, it becomes a light orange, then a dark red, then purplish-brown. This edible mesocarp is composed of a smooth outer cru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nutt
Nutt is an English surname. List of people surnamed Nutt * Alfred Nutt (1856–1910), British publisher *Alfred Young Nutt (1847–1924), English architect and artist *Commodore Nutt (1844–1881), American dwarf who worked for P. T. Barnum *Danny Nutt, American football coach * David Nutt; several people including ** David Nutt, British scientist ** David Nutt, English publisher **David H. Nutt, American lawyer and philanthropist * Dennis Nutt, American basketball player *Dickey Nutt, American basketball coach * Eliza Hall Nutt, American philanthropist and schoolteacher *Emma Nutt, first female telephone switchboard operator *Gordon Nutt (born 1932), English footballer * Grady Nutt, American writer * Houston Nutt, American football coach * Jim Nutt, American artist * John Nutt; several people including ** John Nutt, English pirate ** John Nutt (politician), English MP **John Nutt (printer) Elizabeth Nutt (''c.'' 1666 – November 1746) and John Nutt (? – 1716) were printers and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ohio River
The Ohio River is a long river in the United States. It is located at the boundary of the Midwestern and Southern United States, flowing southwesterly from western Pennsylvania to its river mouth, mouth on the Mississippi River at the southern tip of Illinois. It is the third largest river by discharge volume in the United States and the largest tributary by volume of the north-south flowing Mississippi River that divides the eastern from western United States. It is also the 6th oldest river on the North American continent. The river flows through or along the border of six U.S. state, states, and its drainage basin includes parts of 14 states. Through its largest tributary, the Tennessee River, the basin includes several states of the southeastern U.S. It is the source of drinking water for five million people. The lower Ohio River just below Louisville is obstructed by rapids known as the Falls of the Ohio where the elevation falls in restricting larger commercial navigatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Geological Survey
The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, and the natural hazards that threaten it. The organization's work spans the disciplines of biology, geography, geology, and hydrology. The USGS is a fact-finding research organization with no regulatory responsibility. The agency was founded on March 3, 1879. The USGS is a bureau of the United States Department of the Interior; it is that department's sole scientific agency. The USGS employs approximately 8,670 people and is headquartered in Reston, Virginia. The USGS also has major offices near Lakewood, Colorado, at the Denver Federal Center, and Menlo Park, California. The current motto of the USGS, in use since August 1997, is "science for a changing world". The agency's previous slogan, adopted on the occasion of its hundredth an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species At Risk Act
The ''Species at Risk Act'' (SARA) (the ''Act'') is a piece of Canadian federal legislation which became law in Canada on December 12, 2002. It is designed to meet one of Canada's key commitments under the International Convention on Biological Diversity. The goal of the ''Act'' is to prevent wildlife species in Canada from disappearing by protecting endangered or threatened organisms and their habitats. It also manages species which are not yet threatened, but whose existence or habitat is in jeopardy. SARA defines a method to determine the steps that need to be taken in order to help protect existing relatively healthy environments, as well as recover threatened habitats, although timing and implementation of recovery plans have limitations. It identifies ways in which governments, organizations, and individuals can work together to preserve species at risk and establishes penalties for failure to obey the law. The ''Act'' designates COSEWIC, an independent committee of wildli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monecious
Plant reproductive morphology is the study of the physical form and structure (the morphology) of those parts of plants directly or indirectly concerned with sexual reproduction. Among all living organisms, flowers, which are the reproductive structures of angiosperms, are the most varied physically and show a correspondingly great diversity in methods of reproduction. Plants that are not flowering plants (green algae, mosses, liverworts, hornworts, ferns and gymnosperms such as conifers) also have complex interplays between morphological adaptation and environmental factors in their sexual reproduction. The breeding system, or how the sperm from one plant fertilizes the ovum of another, depends on the reproductive morphology, and is the single most important determinant of the genetic structure of nonclonal plant populations. Christian Konrad Sprengel (1793) studied the reproduction of flowering plants and for the first time it was understood that the pollination process involved ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drupe
In botany, a drupe (or stone fruit) is an indehiscent fruit in which an outer fleshy part ( exocarp, or skin, and mesocarp, or flesh) surrounds a single shell (the ''pit'', ''stone'', or '' pyrena'') of hardened endocarp with a seed (''kernel'') inside. These fruits usually develop from a single carpel, and mostly from flowers with superior ovaries (polypyrenous drupes are exceptions). The definitive characteristic of a drupe is that the hard, lignified stone is derived from the ovary wall of the flower. In an aggregate fruit, which is composed of small, individual drupes (such as a raspberry), each individual is termed a drupelet, and may together form an aggregate fruit. Such fruits are often termed '' berries'', although botanists use a different definition of ''berry''. Other fleshy fruits may have a stony enclosure that comes from the seed coat surrounding the seed, but such fruits are not drupes. Flowering plants that produce drupes include coffee, jujube, ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesocarp
Fruit anatomy is the plant anatomy of the internal structure of fruit. Fruits are the mature ovary or ovaries of one or more flowers. They are found in three main anatomical categories: aggregate fruits, multiple fruits, and simple fruits. Aggregate fruits are formed from a single compound flower and contain many ovaries or fruitlets. Examples include raspberries and blackberries. Multiple fruits are formed from the fused ovaries of multiple flowers or inflorescence. Examples include fig, mulberry, and pineapple. Simple fruits are formed from a single ovary and may contain one or many seeds. They can be either fleshy or dry. In fleshy fruit, during development, the pericarp (ovary wall) and other accessory structures become the fleshy portion of the fruit. The types of fleshy fruits are berries, pomes, and drupes. In some fruits, the edible portion is not derived from the ovary, but rather from the aril, such as the mangosteen or pomegranate, and the pineapple from whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drought Tolerant
Drought tolerance is the ability to which a plant maintains its biomass production during arid or drought conditions. Some plants are naturally adapted to dry conditions'','' surviving with protection mechanisms such as desiccation tolerance, detoxification, or repair of xylem embolism. Other plants, specifically crops like corn, wheat, and rice, have become increasingly tolerant to drought with new varieties created via genetic engineering. The plants behind drought tolerance are complex and involve many pathways which allows plants to respond to specific sets of conditions at any given time. Some of these interactions include stomatal conductance, carotenoid degradation and anthocyanin accumulation, the intervention of osmoprotectants (such as sucrose, glycine, and proline), ROS-scavenging enzymes. The molecular control of drought tolerance is also very complex and is influenced other factors such as environment and the developmental stage of the plant. This control consists ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alvar
An alvar is a biological environment based on a limestone plain with thin or no soil and, as a result, sparse grassland vegetation. Often flooded in the spring, and affected by drought in midsummer, alvars support a distinctive group of prairie-like plants. Most alvars occur either in northern Europe or around the Great Lakes in North America. This stressed habitat supports a community of rare plants and animals, including species more commonly found on prairie grasslands. Lichen and mosses are common species. Trees and bushes are absent or severely stunted. The primary cause of alvars is the shallow exposed bedrock. Flooding and drought, as noted, add to the stress of the site and prevent many species from growing. Disturbance may also play a role. In Europe, grazing is frequent, while in North America, there is some evidence that fire may also prevent encroachment by forest. The habitat also has strong competition gradients, with better competitors occupying the dee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Celtis
''Celtis'' is a genus of about 60–70 species of deciduous trees, commonly known as hackberries or nettle trees, widespread in warm temperate regions of the Northern Hemisphere. The genus is part of the extended hemp family ( Cannabaceae). Description ''Celtis'' species are generally medium-sized trees, reaching tall, rarely up to tall. The leaves are alternate, simple, long, ovate- acuminate, and evenly serrated margins. Diagnostically, ''Celtis'' can be very similar to trees in the Rosaceae and other rose motif families. Small flowers of this monoecious plant appear in early spring while the leaves are still developing. Male flowers are longer and fuzzy. Female flowers are greenish and more rounded. The fruit is a small drupe in diameter, edible in many species, with a dryish but sweet, sugary consistency, reminiscent of a date. Taxonomy Previously included either in the elm family ( Ulmaceae) or a separate family, Celtidaceae, the APG III system places ''Celti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calciphile
A calcicole, calciphyte or calciphile is a plant that thrives in lime rich soil. The word is derived from the Latin 'to dwell on chalk'. Under acidic conditions, aluminium becomes more soluble and phosphate less. As a consequence, calcicoles grown on acidic soils often develop the symptoms of aluminium toxicity, i.e. necrosis, and phosphate deficiency, i.e. anthocyanosis (reddening of the leaves) and stunting. A plant that thrives in acid soils is known as a calcifuge. A plant thriving on sand (which may be acidic or calcic) is termed psammophilic or arenaceous (see also arenite). Examples of calcicole plants * Ash trees ('' Fraxinus'' spp.) * Honeysuckle (''Lonicera'') * ''Buddleja'' * Lilac (''Syringa'') * Beet * ''Clematis'' * ''Sanguisorba minor'' * Some European orchids * Some succulent plants genera ''Sansevieria'' and ''Titanopsis'' or cacti genus ''Thelocactus ''Thelocactus'' is a genus of flowering plants in the cactus family Cactaceae. Members of the genus are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limestone
Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms when these minerals precipitate out of water containing dissolved calcium. This can take place through both biological and nonbiological processes, though biological processes, such as the accumulation of corals and shells in the sea, have likely been more important for the last 540 million years. Limestone often contains fossils which provide scientists with information on ancient environments and on the evolution of life. About 20% to 25% of sedimentary rock is carbonate rock, and most of this is limestone. The remaining carbonate rock is mostly dolomite, a closely related rock, which contains a high percentage of the mineral dolomite, . ''Magnesian limestone'' is an obsolete and poorly-defined term used variously for dolomite, for lime ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
