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	{{~~Taxobox~~		__NOTOC__{{Plantbox
	\| ~~color~~ = ~~lightgreen~~		\| name = ''Taxaceae''
	\| ~~name~~ = ~~Taxaceae~~		\| common_names = Yew
			\| color = IndianRed
	\| image = Eibeyew1web.jpg		\| image = Eibeyew1web.jpg
	\| image_width = ~~250px~~		\| image_width = 200px <!--- leave as 240px if horizontal orientation photo, or change to 180px if vertical -->
	\| image_caption = ''A fleshy aril partly surrounds each seed in the <br>yews; note also immature cones with seed <br>not yet surrounded by the aril''		\| image_caption = ''A fleshy aril partly surrounds each seed in the <br>yews; note also immature cones with seed <br>not yet surrounded by the aril''
	\| regnum = [[Plantae]]		\| regnum = Plantae
	\| divisio = [[Pinophyta]]		\| divisio = Pinophyta
	\| classis = ~~[[Pinophyta\|~~Pinopsida]]		\| classis = Pinopsida
	\| ordo = [[Pinales]]		\| ordo = Pinales
	\| familia = ~~'''~~Taxaceae~~'''~~		\| familia = Taxaceae
	\| ~~familia_authority~~ = ~~S.F. Gray~~		\| genus =
	\| ~~subdivision_ranks~~ = ~~[[Genus~~\|~~Genera]]~~		\| species =
	\| ~~subdivision~~ =		\| subspecies =
	~~'''Taxaceae''' ''sensu stricto''<br/>~~		\| cultivar =
	~~''[[Taxus]]''<br/>~~
	~~''[[Pseudotaxus]]''<br/>~~
	~~''[[Austrotaxus]]''<br/>——<br/>~~
	~~'''[[Cephalotaxaceae]]'''<br/>~~
	~~''[[Torreya]]''<br/>~~
	~~''[[Amentotaxus]]''<br/>~~
	~~''[[Cephalotaxus]]''~~
	}}		}}
			{{Inc\|
			Taxaceae (from the genus Taxus, the classical name, probably from the Greek meaning bow, for which the wood is used). Yew Family. Fig.5. Much-branched trees or shrubs, with resin-tubes in the bark and no true vessels in the secondary wood: leaves alternate, needle-like or scale-like, persistent: stamens borne on the protected portion of more or less apically thickened or peltate scales (sporophylls) forming a small cone: pistillate cones wanting; ovules borne singly or two together on a fleshy or rudimentary carpel (sporophyll), inverted or straight, the outer integument forming an arillus: fruit a dry seed surrounded by the fleshy often highly colored arillus; the receptacle also often enlarged and forming a fleshy part of the fruit.

	~~The family '''~~Taxaceae~~''', commonly called the '''yew''' family, includes three~~ genera and about ~~7 to 12~~ species of ~~[[conifer]]ous [[plant]]s~~, or in ~~other interpretations (see Classification~~, ~~below)~~, ~~six genera~~ and ~~about 30 species~~.		Taxaceae has 8 genera and about 70 species widely distributed, of which 40 belong to the genus Podocarpus. The family is related to the Coniferae, but differs in the reduction of the pistillate cone to a single ovule, in the modification or suppression of the sporophyll, and in the aril or arillus. The closely related Ginkgoaceae has a different staminate inflorescence. Fertilization is by means of pollen-tubes.

	~~They are much branched, small [[tree]]s and [[shrub]]s.~~ The ~~leaves are [[evergreen]], spirally arranged, often twisted at~~ the ~~base to appear 2-ranked. They are linear to lanceolate,~~ and ~~have pale green or white stomatal bands on the undersides~~. The ~~plants are [[Plant sexuality\|dioecious]], rarely [[Plant sexuality\|monoecious]]~~. ~~The male [[conifer cone\|cones]] are 2-5 mm long,~~ and ~~shed [[pollen]] in the early spring~~. The ~~female cones~~ are ~~highly reduced, with just one ovuliferous scale and one seed. As the seed matures~~, the ~~ovuliferous scale develops into a fleshy '''[[aril]]''' partly enclosing the seed. The mature aril is brightly coloured, soft, juicy and sweet, and~~ is ~~eaten by [[bird]]s which then disperse the hard seed undamaged in their droppings~~.		The timber produced by the tropical eastern species of Podocarpus and of Dacrydium (heron pine and damion pine) is highly valued. The yew wood is hard and susceptible of a high polish. It is used in cabinet work and for bows. The seed and shoots of yew are said to be poisonous, but the arillus is harmless.

	~~===Classification===~~		In cultivation in America are a few genera for ornamental purposes: Cephalotaxus, East Asia; Podocarpus, Chile, Japan, Australia, grown in the South; Taxus (Yew), Europe, Asia, North America; Torreya (California Nutmeg), California to Florida.{{SCH}}
	~~[[Image~~:~~Taxaceae.png\|thumb\|240px\|left\|Phylogeny of the Taxaceae and [[Cephalotaxaceae]] - note that both groups have evolved from within the other conifers]]~~		}}
	~~The Taxaceae is now generally included with all other conifers in the order '''[[Pinales]]'''~~, ~~as [[DNA]] analysis has shown that the yews are monophyletic with the other families~~ in the ~~Pinales~~ (~~Chase ''et al''.~~, ~~1993; Price~~, ~~2003)~~, ~~a conclusion supported by [[wikt:micromorphology\|micromorphology]] studies~~ (~~Anderson & Owens~~, ~~2003). Formerly they were often treated as distinct from other conifers by placing them in a separate order [[Taxales]]~~.

	~~The genera ''Torreya'' and ''Amentotaxus'', previously included in~~ this ~~family, are better transferred to the '''[[Cephalotaxaceae]]''', as genetic tests show they~~ are more ~~closely related to ''Cephalotaxus'' than to ''Taxus''. Alternatively, they may be included, with ''Cephalotaxus'',~~ in ~~a broader interpretation of Taxaceae as a single larger family (Price, 2003). In this sense,~~ the ~~Taxaceae includes six genera and about 30 species.~~		==Gallery==
			{{photo-sources}}<!-- remove this line if there are already 3 or more photos in the gallery -->

	~~The differences between the Taxaceae and the Cephalotaxaceae are as follows:~~		<gallery>
	<~~table border="" cellspacing="" cellpadding=""~~>		Image:Upload.png\| photo 1
	~~<tr>~~		Image:Upload.png\| photo 2
	~~<th>Family</th><th> Taxaceae </th><th> Cephalotaxaceae </th>~~		Image:Upload.png\| photo 3
	~~</tr><tr>~~		</gallery>
	~~<td> Cone aril </td><td> partly encloses seed </td><td> fully encloses seed </td></td>~~
	~~</tr><tr>~~
	~~<td> Cone maturation </td><td> 6-8 months</td><td> 18-20 months</td>~~
	</~~tr><tr>~~
	~~<td> Mature seed length </td><td> 5-8 mm *</td><td> 12-40 mm</td>~~
	~~</tr><tr>~~
	~~</table>~~
	~~<nowiki>*</nowiki~~> ~~To 25 mm in ''Austrotaxus''~~

	~~A few botanists have transferred ''Austrotaxus'' to its own family, the '''Austrotaxaceae''', suggesting it may be closer to the '''~~[[~~Podocarpaceae~~]]'~~'' than to the other Taxaceae~~, ~~but genetic evidence does not support this transfer~~.		==References==
			*[[Standard Cyclopedia of Horticulture]], by L. H. Bailey, MacMillan Co., 1963
			<!--- xxxxx *Flora: The Gardener's Bible, by Sean Hogan. Global Book Publishing, 2003. ISBN 0881925381 -->
			<!--- xxxxx *American Horticultural Society: A-Z Encyclopedia of Garden Plants, by Christopher Brickell, Judith D. Zuk. 1996. ISBN 0789419432 -->
			<!--- xxxxx *Sunset National Garden Book. Sunset Books, Inc., 1997. ISBN 0376038608 -->

	==~~References~~==		==External links==
	* ~~Anderson, E. & Owens, J. N. (2003). Analysing the reproductive biology of Taxus: should it be included in Coniferales? ''Acta Hort.'' 615: 233-234. (conclusion is 'yes')<br>~~		*{{wplink}}
	* Chase, M. W. ''et al.'' (1993). Phylogenetics of seed plants, an analysis of nucleotide sequences from the plastid gene ''rbc''L. ''Ann. Missouri Bot. Gard.'' 80: 528-580.<br>
	* Price, R. A. (2003). Generic and familial relationships of the Taxaceae from ''rbc''L and ''mat''K sequence comparisons. ''Acta Hort.'' 615: 235-237.

	{{~~Pinophyta~~}}		{{stub}}
			[[Category:Categorize]]

	~~[[Category~~:~~Taxaceae]]~~		<!-- in order to add all the proper categories, go to http://www.plants.am/wiki/Plant_Categories and copy/paste the contents of the page here, and then follow the easy instructions! -->
	~~[[Category:Conifers]]~~
	~~[[Category:Plant families]]~~

MediaWiki default at 11:12, 31 October 2007

2007-10-31T11:12:37Z

New page

{{Taxobox
| color = lightgreen
| name = Taxaceae
| image = Eibeyew1web.jpg
| image_width = 250px
| image_caption = ''A fleshy aril partly surrounds each seed in the yews; note also immature cones with seed not yet surrounded by the aril''
| regnum = [[Plantae]]
| divisio = [[Pinophyta]]
| classis = [[Pinophyta|Pinopsida]]
| ordo = [[Pinales]]
| familia = '''Taxaceae'''
| familia_authority = S.F. Gray
| subdivision_ranks = [[Genus|Genera]]
| subdivision =
'''Taxaceae''' ''sensu stricto'' 
''[[Taxus]]'' 
''[[Pseudotaxus]]'' 
''[[Austrotaxus]]'' —— 
'''[[Cephalotaxaceae]]''' 
''[[Torreya]]'' 
''[[Amentotaxus]]'' 
''[[Cephalotaxus]]''
}}

The family '''Taxaceae''', commonly called the '''yew''' family, includes three genera and about 7 to 12 species of [[conifer]]ous [[plant]]s, or in other interpretations (see Classification, below), six genera and about 30 species.

They are much branched, small [[tree]]s and [[shrub]]s. The leaves are [[evergreen]], spirally arranged, often twisted at the base to appear 2-ranked. They are linear to lanceolate, and have pale green or white stomatal bands on the undersides. The plants are [[Plant sexuality|dioecious]], rarely [[Plant sexuality|monoecious]]. The male [[conifer cone|cones]] are 2-5 mm long, and shed [[pollen]] in the early spring. The female cones are highly reduced, with just one ovuliferous scale and one seed. As the seed matures, the ovuliferous scale develops into a fleshy '''[[aril]]''' partly enclosing the seed. The mature aril is brightly coloured, soft, juicy and sweet, and is eaten by [[bird]]s which then disperse the hard seed undamaged in their droppings.

===Classification===
[[Image:Taxaceae.png|thumb|240px|left|Phylogeny of the Taxaceae and [[Cephalotaxaceae]] - note that both groups have evolved from within the other conifers]]
The Taxaceae is now generally included with all other conifers in the order '''[[Pinales]]''', as [[DNA]] analysis has shown that the yews are monophyletic with the other families in the Pinales (Chase ''et al''., 1993; Price, 2003), a conclusion supported by [[wikt:micromorphology|micromorphology]] studies (Anderson & Owens, 2003). Formerly they were often treated as distinct from other conifers by placing them in a separate order [[Taxales]].

The genera ''Torreya'' and ''Amentotaxus'', previously included in this family, are better transferred to the '''[[Cephalotaxaceae]]''', as genetic tests show they are more closely related to ''Cephalotaxus'' than to ''Taxus''. Alternatively, they may be included, with ''Cephalotaxus'', in a broader interpretation of Taxaceae as a single larger family (Price, 2003). In this sense, the Taxaceae includes six genera and about 30 species.

The differences between the Taxaceae and the Cephalotaxaceae are as follows:
<table border="" cellspacing="" cellpadding="">
<tr>
<th>Family</th><th> Taxaceae </th><th> Cephalotaxaceae </th>
</tr><tr>
<td> Cone aril </td><td> partly encloses seed </td><td> fully encloses seed </td></td>
</tr><tr>
<td> Cone maturation </td><td> 6-8 months</td><td> 18-20 months</td>
</tr><tr>
<td> Mature seed length </td><td> 5-8 mm *</td><td> 12-40 mm</td>
</tr><tr>
</table>
<nowiki>*</nowiki> To 25 mm in ''Austrotaxus''

A few botanists have transferred ''Austrotaxus'' to its own family, the '''Austrotaxaceae''', suggesting it may be closer to the '''[[Podocarpaceae]]''' than to the other Taxaceae, but genetic evidence does not support this transfer.

==References==
* Anderson, E. & Owens, J. N. (2003). Analysing the reproductive biology of Taxus: should it be included in Coniferales? ''Acta Hort.'' 615: 233-234. (conclusion is 'yes') 
* Chase, M. W. ''et al.'' (1993). Phylogenetics of seed plants, an analysis of nucleotide sequences from the plastid gene ''rbc''L. ''Ann. Missouri Bot. Gard.'' 80: 528-580. 
* Price, R. A. (2003). Generic and familial relationships of the Taxaceae from ''rbc''L and ''mat''K sequence comparisons. ''Acta Hort.'' 615: 235-237.

{{Pinophyta}}

[[Category:Taxaceae]]
[[Category:Conifers]]
[[Category:Plant families]]

Taxaceae - Revision history

WikiWorks at 00:15, 5 May 2009

MediaWiki default at 11:12, 31 October 2007