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==Function==
 
==Function==
Often, rosettes form in perennial plants whose upper foliage dies back with the remaining vegetation protecting the plant. Another form occurs when [[Internode (botany)|internodes]] along a stem are shortened, bringing the leaves closer together, as in [[lettuce]] and [[dandelion]] and some [[succulent]]s.<ref name="biologie.uni-hamburg.de">[http://www.biologie.uni-hamburg.de/b-online/e02/02c.htm Botany online: Features of Flowering Plants - Leaves<!-- Bot generated title -->]</ref> (When plants such as lettuce grow too quickly, the stem lengthens instead, a condition known as ''bolting''.) In yet other forms, the rosette persists at the base of the plant (such as the dandelion), and there is a [[taproot]].
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Often, rosettes form in perennial plants whose upper foliage dies back with the remaining vegetation protecting the plant. Another form occurs when [[internode]]s along a stem are shortened, bringing the leaves closer together, as in [[lettuce]] and [[dandelion]] and some [[succulent]]s.<ref name="biologie.uni-hamburg.de">[http://www.biologie.uni-hamburg.de/b-online/e02/02c.htm Botany online: Features of Flowering Plants - Leaves<!-- Bot generated title -->]</ref> (When plants such as lettuce grow too quickly, the stem lengthens instead, a condition known as ''bolting''.) In yet other forms, the rosette persists at the base of the plant (such as the dandelion), and there is a [[taproot]].
 
===Protection===
 
===Protection===
 
Part of the protective function of a rosette like the dandelion is that it is hard to pull from the ground; the leaves come away easily while the taproot is left intact.
 
Part of the protective function of a rosette like the dandelion is that it is hard to pull from the ground; the leaves come away easily while the taproot is left intact.
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Another kind of protection is provided by the ''caulescent rosette'' which is part of the growth form of the giant ''[[Espeletia]]'' genus in South America, which has a well-developed stem above the ground.<ref>[http://www.evoandes.net/espeletiapage.html shows many images]</ref> In tropical alpine environments a wide variety of plants in different plant families and different parts of the world have evolved this [[growth form]] characterized by evergreen rosettes growing above [[marcescent]] leaves. Examples where this arrangement has been confirmed to improve survival, help water balance, or protect the plant from cold injury are ''[[Espeletia]] schultzii'' and ''Espeletia timotensis'', both from the [[Andes]].<ref>[http://www.csa.com/partners/viewrecord.php?requester=gs&collection=ENV&recid=688033&q=marcescent+leaves+&uid=788491162&setcookie=yes Goldstein, G. and Meinzer, F.1983. Influence of insulating dead leaves and low temperatures on water balance in an Andean giant rosette plant. ''Plant, Cell & Environment'' 6: 649-656.]</ref><ref>[http://links.jstor.org/sici?sici=0006-3606(197903)11%3A1%3C43%3AFODLIE%3E2.0.CO%3B2-P Smith, Alan P.1979. Function of dead leaves in ''Espeletia schultzii'' (Compositae), and Andean caulescent rosette species. ''Biotropica'' 11: 43-47.]</ref>
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Another kind of protection is provided by the ''caulescent rosette'' which is part of the growth form of the giant ''[[Espeletia]]'' genus in South America, which has a well-developed stem above the ground.<ref>[http://www.evoandes.net/espeletiapage.html shows many images]</ref> In tropical alpine environments a wide variety of plants in different plant families and different parts of the world have evolved this [[growth form]] characterized by evergreen rosettes growing above [[marcescent]] leaves. Examples where this arrangement has been confirmed to improve survival, help water balance, or protect the plant from cold injury are ''[[Espeletia]] schultzii'' and ''Espeletia timotensis'', both from the Andes.<ref>[http://www.csa.com/partners/viewrecord.php?requester=gs&collection=ENV&recid=688033&q=marcescent+leaves+&uid=788491162&setcookie=yes Goldstein, G. and Meinzer, F.1983. Influence of insulating dead leaves and low temperatures on water balance in an Andean giant rosette plant. ''Plant, Cell & Environment'' 6: 649-656.]</ref><ref>[http://links.jstor.org/sici?sici=0006-3606(197903)11%3A1%3C43%3AFODLIE%3E2.0.CO%3B2-P Smith, Alan P.1979. Function of dead leaves in ''Espeletia schultzii'' (Compositae), and Andean caulescent rosette species. ''Biotropica'' 11: 43-47.]</ref>
    
==Taxonomies==
 
==Taxonomies==
Many plant [[family (taxonomy)|families]] have varieties with rosette morphology; they are particularly common in [[Asteraceae]] (such as [[dandelion]]s), [[Brassicaceae]] (such as [[cabbage]]), and [[Bromeliaceae]]. The fern, ''[[Blechnum fluviatile]]'' or [[New Zealand]] Water Fern (''Kiwikiwi'') is a rosette plant.
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Many plant [[family (taxonomy)|families]] have varieties with rosette morphology; they are particularly common in [[Asteraceae]] (such as [[dandelion]]s), [[Brassicaceae]] (such as [[cabbage]]), and [[Bromeliaceae]]. The fern, ''[[Blechnum fluviatile]]'' or New Zealand Water Fern (''Kiwikiwi'') is a rosette plant.
    
==Form==
 
==Form==

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