![]() The greatest number of orchid species is found in cloud-forest associations in tropical regions, usually on mountainsides where the clouds brush the mountain day and night. Orchids thrive in regions from sea level to at least 4,600 metres (15,000 feet) in elevation. The introduced Asian species Zeuxine strateumatica in southern Florida is now widespread and may be considered a weed. In some areas of the United States, Platanthera ciliaris might almost be considered a weed. Several species of Spiranthes, Habenaria, and other orchids are found in roadside ditches, often in wet, boggy situations. A number of species of the North Temperate Zone are found in bogs, prairies, grasslands, and hardwood forests. At least four species have been reported from north of the Arctic Circle. Although the family is primarily tropical, a number of species are found in the northern and southern temperate zones. Orchids have a wide ecological distribution when the entire family is considered. Further, the diversity of structure among orchid flowers can be attributed mainly to the methods of pollination found in the family or to the fact that the family is adapted for the utilization of a number of different types of pollinators. The wide range of growth habits varies from those in which the plant is reduced to no more than roots ( Dendrophylax), to saprophytic plants apparently lacking chlorophyll ( Corallorhiza), to gigantic plants ( Arundina) that superficially resemble a bamboo. Orchid flowers vary tremendously in size from the minute flowers of some species of the genus Pleurothallis, which are no more than about 2 mm (0.1 inch) in diameter, to the large ones of Brassia, which may be more than 38 cm (15 inches) from the tips of the lateral sepals (petallike structures) to the tip of the dorsal sepal. Orchids are primarily herbaceous (nonwoody), although some species may be vines, vinelike, or somewhat shrubby. It is through the combination of several characteristics that a family of flowering plants, the Orchidaceae, emerges. Even the special characteristics of orchid flowers, such as the masses of pollen called pollinia, the joining of the stamens and pistil to form a column, and the tiny seeds without endosperm are found individually in other groups of flowering plants. Learn about orchids and observe an orchid expert pollinating a lady's slipper orchid with the pollen of a second fine specimen, and the method of cross-breeding in a laboratory See all videos for this articleĪs a group, the orchids are different from other plants but only in the morphological (structural) characteristics associated with the flower and its organization. SpaceNext50 Britannica presents SpaceNext50, From the race to the Moon to space stewardship, we explore a wide range of subjects that feed our curiosity about space!.Learn about the major environmental problems facing our planet and what can be done about them! Saving Earth Britannica Presents Earth’s To-Do List for the 21st Century.Britannica Beyond We’ve created a new place where questions are at the center of learning. ![]() 100 Women Britannica celebrates the centennial of the Nineteenth Amendment, highlighting suffragists and history-making politicians.COVID-19 Portal While this global health crisis continues to evolve, it can be useful to look to past pandemics to better understand how to respond today.Student Portal Britannica is the ultimate student resource for key school subjects like history, government, literature, and more.Demystified Videos In Demystified, Britannica has all the answers to your burning questions.This Time in History In these videos, find out what happened this month (or any month!) in history.#WTFact Videos In #WTFact Britannica shares some of the most bizarre facts we can find.Britannica Classics Check out these retro videos from Encyclopedia Britannica’s archives.Britannica Explains In these videos, Britannica explains a variety of topics and answers frequently asked questions. ![]()
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