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''Piperia yadonii'', also known as Yadon's piperia or Yadon's rein orchid, is an endangered orchid endemic to a narrow range of coastal habitat in northern Monterey County, California. In 1998 this plant was designated as an endangered species by the United States government, the major threat to its survival being continuing land development from an expanding human population and associated habitat loss.〔United States Fish and Wildlife Service, ''Endangered and threatened wildlife and plants: Final rule listing five plants from Monterey County, California as endangered or threatened''. Federal Register 63: 43100–43116 (1998)〕 One of the habitats of Yadon’s Piperia, the Del Monte Forest near Monterey, California, is the subject of a federal lawsuit, based upon endangerment of this organism along with several other endangered species. This wildflower may lie dormant in a given year and not emerge above the soil surface from its tuberous substructure. After leafing out in the spring, it will produce flowers on erect spikes, each flower possessing both green and white petals. It prefers sandy soils, and subsists on nutrient extraction from intermediate fungal organisms. ==Description== Along with most other orchids ''P. yadonii'': (a) is a bisexual perennial green plant that grows from buried tubers; manifests a fruit capsule bearing numerous minute seeds; (b) exhibits pollen that is sticky, and which is removed as sessile anther sacs; and (c) has a stigma fused with its style into a column. There are a total of eight species in the genus ''Piperia'', which is named for American botanist Charles V. Piper. The genus members manifest generally cylindrical spikes or racemes. As with other ''Piperia'', Yadon's Piperia exhibits a single veined flower one to two millimeters in width and a basal rosette leaf formation. The subsurface architecture of this terrestrial wild orchid consists of a rhizome structure, from which emanate tubers. The rhizome extracts nutrients from fungal intermediates and may also store some of these nutrients. A basal rosette of leaves develops from the tuber at the surface of the soil, each of the two or three leaves being lanceolate in shape.〔Morgan & Ackerman, Lindleyana 5:205–211 (1990)〕 Each leaf ranges from 10 to 15 centimeters in length and 20 to35 millimeters in width. Leaves of younger plants are often more diminutive in size. The dense inflorescence is borne on a single erect vertical spike varying from 12 to 55 centimeters in height.〔''The Jepson manual: higher plants of California'', Hickman, JC, ed., University of California Press, Berkeley, Ca. (1993)〕 Each flower has a spur of length 1.5 to 5 millimeters, short compared to other members of the genus. Yadon’s Piperia typically presents three upper tepals, each of which contains both green and white pigmentation; moreover, there are three lower tepals that are white only. The earliest blooming time is June. When ''P. yadonii'' blooms, as late as August, all of its sepals and petals may be purely white. Another key identification feature is the characteristically abbreviated spur, which typically measures 1.5 to 6.0 millimeters in length. ''P. yadonii'' 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Piperia yadonii」の詳細全文を読む スポンサード リンク
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