Monday, November 16, 2009

A question for botonists?

tell me about


Broadleaf plantago


smart weed polygonom


Dandelion Taraxacum


And


Wood sorrel oxalis

A question for botonists?
The Broadleaf Plantain or Greater Plantago (Plantago major) is a member of the plantago family, Plantaginaceae. In North America, this plant is primarily a weed, though it is edible and is used in herbal medicine. The plant is native to Europe, and is believed to be one of the first plants to naturalize in the colonies.





This plant does best in compacted soils, and hence is sometimes called "roadweed". It propagates primarily by seeds, which are held on the long, narrow spikes which rise well above the foliage.





Some cultivars of this plant are used in gardens.





The Plant is commonly found on field boundaries as it is tolerant to pestcides and herbicides. It is wind-pollenated, and a cause of summer allergies when in flower.





Crushed leaves can be applied directly to the skin to stop bleeding, bee stings and insect bites. Psyllium seeds are a bulk laxative.





The leaves are completely edible, but can be somewhat tough. The taste is that of very bitter salad greens with a lingering aftertaste like spinach. Young leaves are recommended as they are more tender. The leaves when dried make a good tea. The sinews from the broadleaf plantain are very pliable and tough when fresh and/or wettened, and can be used to make small cords or braiding. When dry the sinews harden but also become more brittle.





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Smartweed - Polygonum hydropiperoides (from the family Polygonaceae); the leaves of this plant are alternate with tubelike sheathing stipules (ocrea) and stems with swollen nodes. The flowers have no petals, but the sepals resemble petals. The fruit is an achene.





Smartweed grows in wet meadows, marshes, shorelines of lakes and ponds, and open areas in wet woodlands. It is often found in extensive colonies along shorelines and in exposed bottoms of ponds or lakes during times of low water. It may also grow in drainage and irrigation ditches and canals. The seeds are dispersed by animals or by water.





Dense colonies of P. hydropiperoides can impede water flow in irrigation ditches and restrict recreational activities along shoreline areas. The seeds of smartweed are eaten by birds, waterfowl and several small mammals





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Dandelion (Taraxacum) is a large genus of flowering plants in the family Asteraceae. They are tap-rooted biennial or perennial herbaceous plants, native to temperate areas of the Northern Hemisphere of the Old World.





The leaves are 5-25 cm long, simple and basal, entire or lobed, forming a rosette above the central taproot. As the leaves grow outward they push down the surrounding vegetation, such as grass in a lawn, killing the vegetation by cutting off the sunlight. A bright yellow flower head (which is open in the daytime but closes at night) is borne singly on a hollow stem (scape) which rises 4-30 cm above the leaves and exudes a milky sap (latex) when broken. A rosette may produce several flowering stems at a time. The flower head is 2-5 cm in diameter and consists entirely of ray florets.





The flower matures into a globe of fine filaments that are usually distributed by wind, carrying away the seed-containing achenes. This globe (receptacle) is called the "dandelion clock", and blowing it apart is a popular pastime for children. In German it's called a Pusteblume, translated as "blow flower". The number of blows required to completely rid the clock of its seeds is deemed to be the time of day. The flower head is surrounded by bracts (sometimes mistakenly called sepals) in two series. The inner bracts are erect until the seeds mature, then flex down to allow the seeds to disperse; the outer bracts are always reflexed downward. Some species drop the "parachute" (called a pappus, modified sepals) from the achenes. Between the pappus and the achene, there is a stalk called beak, which elongates as the fruit matures. The beak breaks off from the achene quite easily.





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Common wood sorrel (Oxalis acetosella) is a plant from the family Oxalidaceae, common in most of Europe and parts of Asia. It flowers for a few months during the spring, with small white flowers with pink streaks. Red or violet flowers also occur rarely. The binomial name Oxalis acetosella is because of its sour taste.





The leaflets are made up by three heart-shaped leaves, folded through the middle. The stalk is red/brown, and during the night or when it rains both flowers and leaves contract.





Historically, people have extracted calcium oxalate, or "sal acetosella" from the plant, through boiling. It is slightly toxic, as oxalic acid is known to interfere with food digestion.





Another common wood sorrel is Oxalis montana, a North American species found from New England and Nova Scotia to Wisconsin and Manitoba. It is similar to the species described above, but the petals are noticeably notched.





The common wood sorrel is sometimes referred to as a shamrock (due to its three-leaf clover-like motif) and given as as gift on St. Patrick's Day.


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