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An ephemeral plant is one marked by short life cycles. The word ephemeral means transitory or quickly fading. In regard to plants, it refers to several distinct growth strategies. The first, spring ephemeral, refers to perennial plants that emerge quickly in the spring and die back to their underground parts after a short growth and reproduction phase. Desert ephemerals are plants which are adapted to take advantage of the short wet periods in arid climates. Mud-flat annuals take advantage of short periods of low water. In areas subjected to recurring human disturbance, such as plowing, weedy ephemerals are very short lived plants whose entire life cycle takes less than a growing season. In each case, the species has a life cycle timed to exploit a short period when resources are freely available.〔Keddy, P.A. 2007. Plants and Vegetation: Origins, Processes, Consequences. Cambridge University Press, Cambridge, UK. 666 p. Chapter 3, Resources.〕 ==Spring ephemerals== Spring ephemeral describes a life habit of perennial woodland wildflowers which develop aerial parts (i.e. stems, leaves, and flowers) of the plant early each spring and then quickly bloom, and produce seed. The leaves often wither leaving only underground structures (i.e. roots, rhizomes, and bulbs) for the remainder of the year. This strategy is very common in herbaceous communities of deciduous forests as it allows small herbaceous plants to take advantage of the high levels of sunlight reaching the forest floor prior to formation of a canopy by woody plants. Examples include: spring beauties, trilliums, and harbinger of spring.〔Archibold, O. W. 1995. Ecology of World Vegetation. London: Chapman and Hall.〕 Spring ephemerals include: *''Anemone nemorosa'' (wood anemone) *''Claytonia sp.'' (spring beauty) *''Dicentra canadensis'' (squirrel corn) *''Dicentra cucullaria'' (Dutchman's breeches) *''Dicentra eximia'' (turkey corn) *''Eranthis'' (winter aconite) *''Erigenia bulbosa'' (harbinger of spring) *''Erythronium americanum'' (yellow trout lily) *''Galanthus'' (snowdrop) *''Hepatica nobilis'' *''Houstonia caerulea'' (azure bluet) *''Hyacinthoides non-scripta'' (bluebell) *''Iris cristata'' (dwarf crested iris) *''Jeffersonia diphylla'' (twinleaf) *''Lamprocapnos spectabilis'' (formerly ''Dicentra spectabilis'', bleeding heart) *''Mertensia virginica'' (Virginia bluebells) *''Ranunculus ficaria'' (lesser celandine) *''Sanguinaria canadensis'' (bloodroot) *''Stylophorum diphyllum'' (celandine poppy, wood poppy) *''Thalictrum thalictroides'' (rue anemone) *''Tiarella cordifolia'' (foamflower) *''Trillium '' 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「Ephemeral plant」の詳細全文を読む スポンサード リンク
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