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''Penstemon haydenii'', the blowout beardtongue or blowout penstemon, is a species of beardtongue in the Plantaginaceae family. The warm-season perennial plant is native to nine counties in the Nebraska Sand Hills and a single location in Carbon County, Wyoming.〔 The plant has a milky-blue color with a waxy cuticle, pale purple leaves, and alternating leaf pattern with one central stock. The flowers, while in the inflorescence stage, originate from the bases of the leaves of the plant. Blowout penstemon flowers from May until early June and drops the seeds late August into September. Blowout penstemon grows on bare sand dunes. It is resistant to the abrasive forces of the blowing sands with its incorporation of a protective thick waxy cuticle. Other plants are often cut off by the scouring sands as they sprout. Another adaptive feature for the blowout penstemon plant is the lifespan of the seeds. The seeds dropped in late August into September can remain buried dormant in the sandy soils for decades and still remain viable. Prolonged wet conditions and abrasion are required for breaking dormancy and seed germination. The plant is primarily an out-crosser (transfers genes from one plant of the same species to another plant of the same or closely related species); although studies show that it is potentially self-fertile.〔Fertig, Walter. 2000. Status of Blowout Penstemon (''Penstemon haydenii'') in Wyoming.” Prepared by the Wyoming Natural Diversity Database for the Wyoming Cooperative Fish and Wildlife Research Unit, U.S. Fish and Wildlife Service, and Wyoming Game and Fish Department.〕 == Habitat == Blowout penstemon was only known from the Sandhills of Nebraska until the recent discovery of limited populations in Wyoming. Blowout penstemon is only found in sandy locations with little to no vegetation present. Due to the uncompetitive nature of the plant it is easily outcompeted by other plants in the succession scheme. The ever-shifting sandy soils of the Sandhills provide blowout penstemon with an ideal environment with little to no competition for water, nutrients, and sunlight. The nature of the plant is to develop these blowout conditions and promote succession. Blowouts are the only habitat to which the plant grows, hence the name. The Sandhills of western Nebraska provide just this habitat needed for the blowout penstemon to grow and survive. 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「Penstemon haydenii」の詳細全文を読む スポンサード リンク
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