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42-586: The Ohm Hills, most of which are densely wooded, whose southeastern foothills form the Bleicherode Hills , lie in the county of Eichsfeld on its boundary with Nordhausen . They are located between Weißenborn-Lüderode to the north, Bleicherode to the southeast, Worbis to the south and Teistungen to the west, and extend from the upper reaches of the River Helme in the north to the Wipper in

84-464: A carbohydrate energy source. The carbohydrate source can be combinations of discrete sugars or can be derived from other sources such as banana , pineapple , peach , or even tomato puree or coconut water . After the preparation of the agar medium, it is poured into test tubes or jars which are then autoclaved (or cooked in a pressure cooker) to sterilize the medium. After cooking, the medium begins to gel as it cools. The taxonomy of this family

126-401: A seta , knocking the pollinator off the flower. After pollination, the sepals and petals fade and wilt, but they usually remain attached to the ovary. In 2011, Bulbophyllum nocturnum was discovered to flower nocturnally. Some species, such as in the genera Phalaenopsis , Dendrobium , and Vanda , produce offshoots or plantlets formed from one of the nodes along the stem , through

168-480: A spur of the labellum ( 8 in the illustration above), or on the point of the sepals, or in the septa of the ovary, the most typical position amongst the Asparagales . In orchids that produce pollinia, pollination happens as some variant of the following sequence: when the pollinator enters into the flower, it touches a viscidium, which promptly sticks to its body, generally on the head or abdomen. While leaving

210-551: A velamen , has the function of absorbing humidity. It is made of dead cells and can have a silvery-grey, white or brown appearance. In some orchids, the velamen includes spongy and fibrous bodies near the passage cells, called tilosomes. The cells of the root epidermis grow at a right angle to the axis of the root to allow them to get a firm grasp on their support. Nutrients for epiphytic orchids mainly come from mineral dust, organic detritus, animal droppings and other substances collecting among on their supporting surfaces. The base of

252-478: A different species of bee, so as to enforce proper cross-pollination. A rare achlorophyllous saprophytic orchid growing entirely underground in Australia, Rhizanthella slateri , is never exposed to light, and depends on ants and other terrestrial insects to pollinate it. Catasetum , a genus discussed briefly by Darwin , actually launches its viscid pollinia with explosive force when an insect touches

294-453: A large a population of yews . Amongst the species of fungi occurring here are: king boletes , bay boletes and St. George's mushrooms . Roe deer and wild boar , red fox , hare , great spotted and green woodpeckers and the rare red kite have also made their home in this protected area . The Bleicherode Hills are a popular destination for locals and visitors to Bleicherode and the surrounding settlements. One particular attraction

336-516: A rather coarser, self-published, region classification, within which the landscape of "Ohm Hills-Bleicherode Hills" is enclosed by the landscape unit "North Thuringian Buntsandstein Land". The muschelkalk ridges of the Ohm Hills and Bleicherode Hills are shown in both classifications as one contiguous natural region. They appear as a continuation of the hills fringing the northwestern perimeter of

378-455: A semiterrestrial or rock-hugging (" lithophyte ") orchid, show a sparkling silver and gold veining on a light green background. The cordate leaves of Psychopsiella limminghei are light brownish-green with maroon-puce markings, created by flower pigments. The attractive mottle of the leaves of lady's slippers from tropical and subtropical Asia ( Paphiopedilum ), is caused by uneven distribution of chlorophyll. Also, Phalaenopsis schilleriana

420-538: A single mass. Each time pollination succeeds, thousands of ovules can be fertilized. Pollinators are often visually attracted by the shape and colours of the labellum. However, some Bulbophyllum species attract male fruit flies ( Bactrocera and Zeugodacus spp.) solely via a floral chemical which simultaneously acts as a floral reward (e.g. methyl eugenol , raspberry ketone , or zingerone ) to perform pollination. The flowers may produce attractive odours. Although absent in most species, nectar may be produced in

462-635: A sticky disc near the top of the column. Just below the pollinia is a second, larger sticky plate called the stigma . The complex mechanisms that orchids have evolved to achieve cross-pollination were investigated by Charles Darwin and described in Fertilisation of Orchids (1862). Orchids have developed highly specialized pollination systems, thus the chances of being pollinated are often scarce, so orchid flowers usually remain receptive for very long periods, rendering unpollinated flowers long-lasting in cultivation. Most orchids deliver pollen in

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504-418: Is a pastel pink orchid with leaves spotted dark green and light green. The jewel orchid ( Ludisia discolor ) is grown more for its colorful leaves than its white flowers. Some orchids, such as Dendrophylax lindenii (ghost orchid), Aphyllorchis and Taeniophyllum depend on their green roots for photosynthesis and lack normally developed leaves, as do all of the heterotrophic species. Orchids of

546-417: Is achieved by removing the pollinia with a small instrument such as a toothpick from the pollen parent and transferring them to the seed parent. Some orchids mainly or totally rely on self-pollination , especially in colder regions where pollinators are particularly rare. The caudicles may dry up if the flower has not been visited by any pollinator, and the pollinia then fall directly on the stigma. Otherwise,

588-557: Is found in the tropics . Orchidaceae is one of the two largest families of flowering plants, along with the Asteraceae . It contains about 28,000 currently accepted species distributed across 763 genera . The Orchidaceae family encompasses about 6–11% of all species of seed plants . The largest genera are Bulbophyllum (2,000 species), Epidendrum (1,500 species), Dendrobium (1,400 species) and Pleurothallis (1,000 species). It also includes Vanilla (the genus of

630-550: Is in constant flux, as new studies continue to clarify the relationships between species and groups of species, allowing more taxa at several ranks to be recognized. The Orchidaceae is currently placed in the order Asparagales by the APG III system of 2009. Five subfamilies are recognised. The cladogram below was made according to the APG system of 1998. It represents the view that most botanists had held up to that time. It

672-592: Is often called a backbulb. Backbulbs still hold nutrition for the plant, but then a pseudobulb usually takes over, exploiting the last reserves accumulated in the backbulb, which eventually dies off, too. A pseudobulb typically lives for about five years. Orchids without noticeable pseudobulbs are also said to have growths, an individual component of a sympodial plant. Like most monocots , orchids generally have simple leaves with parallel veins , although some Vanilloideae have reticulate venation . Leaves may be ovate, lanceolate, or orbiculate, and very variable in size on

714-641: Is the August Petermann nature educational trail . At various stations it gives interesting insights into the natural world. The peaks of the Bleicherode Hills in its narrower sense include the following – with heights in metres above sea level (NHN) : The following outliers are also counted as part of the Bleicherode Hills: The rivers and streams of the Bleicherode Hills include the: Smaller streams also rise in

756-419: Is used as a food reserve for wintry periods, and provides for the development of the other one, from which visible growth develops. In warm and constantly humid climates, many terrestrial orchids do not need pseudobulbs. Epiphytic orchids, those that grow upon a support, have modified aerial roots that can sometimes be a few meters long. In the older parts of the roots, a modified spongy epidermis , called

798-587: The Thuringian Basin interrupted only by the Lower Eichsfeld lowland. Neighbouring natural regions listed clockwise are: The following hills and high points belong to the Ohm Hills in its narrower sense and its foothills to the north and east, which are considered part of neighbouring natural regions, with elevations in metres above sea level (NN) : The rivers and streams in the Ohm Hills include the: The Elbe-Weser Watershed runs through

840-509: The Ziegenrück , is situated about 1 km south-southeast of Buhla. Beech and, to a lesser extent, pine are the predominant trees growing on the muschelkalk soil of the Bleicherode Hills. Amongst the many rare plant and animal species are 14 native species of orchid . It is also the northernmost location for the juneberry . In addition there is a very interesting group of rare mixed wood species like limes and Scots elms as well as

882-454: The vanilla plant ), the type genus Orchis , and many commonly cultivated plants such as Phalaenopsis and Cattleya . Moreover, since the introduction of tropical species into cultivation in the 19th century, horticulturists have produced many hybrids and cultivars . Orchids are easily distinguished from other plants, as they share some very evident derived characteristics or synapomorphies . Among these are: bilateral symmetry of

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924-712: The Bleicherode Hills, such as the Bleibach near Bleicherode and the Friede (crossed by the A 38 's Friede Viaduct) near Sollstedt. The settlements of the Bleicherode Hills include: Orchid Orchids are plants that belong to the family Orchidaceae ( / ˌ ɔːr k ɪ ˈ d eɪ s i . iː , - s i . aɪ / ), a diverse and widespread group of flowering plants with blooms that are often colourful and fragrant. Orchids are cosmopolitan plants that are found in almost every habitat on Earth except glaciers . The world's richest diversity of orchid genera and species

966-679: The Ohm Hills. Whilst the Hahle is part of the catchment area of the Leine and Weser rivers, the Bode, Helme and Wipper are in the Elbe 's drainage basin . The settlements in and on the edge of the Ohm Hills include: Bleicherode Hills The Bleicherode Hills ( German : Bleicheröder Berge or Bleicheroder Berge ) in the counties of Nordhausen and Eichsfeld in North Thuringia are

1008-428: The accumulation of growth hormones at that point. These shoots are known as keiki . Epipogium aphyllum exhibits a dual reproductive strategy, engaging in both sexual and asexual seed production. The likelihood of apomixis playing a substantial role in successful reproduction appears minimal. Within certain petite orchid species groups, there is a noteworthy preparation of female gametes for fertilization preceding

1050-499: The act of pollination. The ovary typically develops into a capsule that is dehiscent by three or six longitudinal slits, while remaining closed at both ends. The seeds are generally almost microscopic and very numerous, in some species over a million per capsule. After ripening, they blow off like dust particles or spores. Most orchid species lack endosperm in their seed and must enter symbiotic relationships with various mycorrhizal basidiomyceteous fungi that provide them

1092-554: The anther may rotate and then enter the stigma cavity of the flower (as in Holcoglossum amesianum ). The slipper orchid Paphiopedilum parishii reproduces by self-fertilization . This occurs when the anther changes from a solid to a liquid state and directly contacts the stigma surface without the aid of any pollinating agent or floral assembly. The labellum of the Cypripedioideae is poke bonnet-shaped , and has

1134-611: The east-southeastern foothills of the Ohm Hills in the Lower Eichsfeld . They reach a maximum height of 460.8 m above  sea level (NHN) at the summit of the Ziegenrück. Together with the Ohm Hills they cover an area of about 76 km² of which the Bleicherode Hills make up roughly 16  km² of the total landscape area. The heavily wooded Bleicherode Hills are located between Buhla and Kraja to

1176-537: The flower ( zygomorphism ), many resupinate flowers, a nearly always highly modified petal (labellum), fused stamens and carpels , and extremely small seeds . All orchids are perennial herbs that lack any permanent woody structure. They can grow according to two patterns: Terrestrial orchids may be rhizomatous or form corms or tubers . The root caps of terrestrial orchids are smooth and white. Some sympodial terrestrial orchids, such as Orchis and Ophrys , have two subterranean tuberous roots . One

1218-536: The flower develops, it undergoes a twisting through 180°, called resupination , so that the labellum lies below the column . The labellum functions to attract insects, and in resupinate flowers, also acts as a landing stage, or sometimes a trap. The reproductive parts of an orchid flower are unique in that the stamens and style are joined to form a single structure, the column . Instead of being released singly, thousands of pollen grains are contained in one or two bundles called pollinia that are attached to

1260-436: The flower, it pulls the pollinium out of the anther, as it is connected to the viscidium by the caudicle or stipe. The caudicle then bends and the pollinium is moved forwards and downwards. When the pollinator enters another flower of the same species, the pollinium has taken such position that it will stick to the stigma of the second flower, just below the rostellum, pollinating it. In horticulture, artificial orchid pollination

1302-409: The flowers to gather volatile chemicals they require to synthesize pheromonal attractants. Males of such species as Euglossa imperialis or Eulaema meriana have been observed to leave their territories periodically to forage for aromatic compounds, such as cineole, to synthesize pheromone for attracting and mating with females. Each type of orchid places the pollinia on a different body part of

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1344-515: The function of trapping visiting insects. The only exit leads to the anthers that deposit pollen on the visitor. In some extremely specialized orchids, such as the Eurasian genus Ophrys , the labellum is adapted to have a colour, shape, and odour which attracts male insects via mimicry of a receptive female. Pollination happens as the insect attempts to mate with flowers. Many neotropical orchids are pollinated by male orchid bees , which visit

1386-430: The genus Corallorhiza (coralroot orchids) lack leaves altogether and instead have symbiotic or parasitic associations with fungal mycelium, though which they absorb sugars. Orchid flowers have three sepals , three petals and a three-chambered ovary . The three sepals and two of the petals are often similar to each other but one petal is usually highly modified, forming a "lip" or labellum . In most orchid genera, as

1428-461: The individual plant. Their characteristics are often diagnostic. They are normally alternate on the stem, often folded lengthwise along the centre ("plicate"), and have no stipules . Orchid leaves often have siliceous bodies called stegmata in the vascular bundle sheaths (not present in the Orchidoideae ) and are fibrous. The structure of the leaves corresponds to the specific habitat of

1470-401: The largest orchid in the world, Grammatophyllum speciosum (giant orchid), it can reach three meters. Some Dendrobium species have long, canelike pseudobulbs with short, rounded leaves over the whole length; some other orchids have hidden or extremely small pseudobulbs, completely included inside the leaves. With ageing the pseudobulb sheds its leaves and becomes dormant. At this stage it

1512-418: The necessary nutrients to germinate, so almost all orchid species are mycoheterotrophic during germination and reliant upon fungi to complete their lifecycles. Only a handful of orchid species have seed that can germinate without mycorrhiza , namely the species within the genus Disa with hydrochorous seeds. As the chance for a seed to meet a suitable fungus is very small, only a minute fraction of all

1554-700: The north, Bleicherode to the east, Sollstedt to the south, Breitenworbis in the southwest and Haynrode to the northwest. They rise between the Krajaer Bach (a tributary of the River Bode ) and the Bode to the north and the Wipper to the south. To the southeast is the Hainleite , to the south the Dün , whilst roughly to the southwest is the der Eichsfeld-Hainich-Werra Valley Nature Park . Their highest hill,

1596-663: The plant. Species that typically bask in sunlight, or grow on sites which can be occasionally very dry, have thick, leathery leaves and the laminae are covered by a waxy cuticle to retain their necessary water supply. Shade-loving species, on the other hand, have long, thin leaves. The leaves of most orchids are perennial, that is, they live for several years, while others, especially those with plicate leaves as in Catasetum , shed them annually and develop new leaves together with new pseudobulbs. The leaves of some orchids are considered ornamental. The leaves of Macodes sanderiana ,

1638-417: The seeds released grow into adult plants. In cultivation, germination typically takes weeks. Horticultural techniques have been devised for germinating orchid seeds on an artificial nutrient medium, eliminating the requirement of the fungus for germination and greatly aiding the propagation of ornamental orchids. The usual medium for the sowing of orchids in artificial conditions is agar gel combined with

1680-638: The south. To the north and west the range is adjoined by historic landscape of the Lower Eichsfeld ( Untereichsfeld ), further south is the ridge of the Dün and to the southwest the Eichsfeld-Hainich-Werra Valley Nature Park . According to "Kassel map" of the natural regional classification of Germany the Ohm Hills are grouped as follows: The Thuringian State office for the Environment and Geology uses

1722-419: The stem of sympodial epiphytes, or in some species essentially the entire stem, may be thickened to form a pseudobulb that contains nutrients and water for drier periods. The pseudobulb typically has a smooth surface with lengthwise grooves, and can have different shapes, often conical or oblong. Its size is very variable; in some small species of Bulbophyllum , it is no longer than two millimeters, while in

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1764-594: Was supported by morphological studies , but never received strong support in molecular phylogenetic studies. Apostasioideae : 2 genera and 16 species, south-eastern Asia Cypripedioideae : 5 genera and 130 species, from the temperate regions of the world, as well as tropical America and tropical Asia Vanilloideae : 15 genera and 180 species, humid tropical and subtropical regions, eastern North America Epidendroideae : more than 500 genera and more or less 20,000 species, cosmopolitan Orchidoideae : 208 genera and 3,630 species, cosmopolitan In 2015,

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