- Picea engelmannii
Taxobox
name = "Picea engelmannii"
status = LR/lc | status_system = IUCN2.3
image_width = 240px
image_caption = Foliage and cone
regnum =Plant ae
divisio =Pinophyta
classis = Pinopsida
ordo =Pinales
familia =Pinaceae
genus = "Picea"
species = "P. engelmannii"
binomial = "Picea engelmannii"
binomial_authority = Parry ex Engelm."Picea engelmannii" (Engelmann Spruce) is a species of
spruce native to westernNorth America , from centralBritish Columbia and southwestAlberta , southwest to northernCalifornia and southeast toArizona andNew Mexico ; there are also two isolated populations in northernMexico . It is mostly a high altitudemountain tree, growing at 900-3650 m altitude, rarely lower in the northwest of the range; in many areas it reaches the alpine tree line.It is a medium-sized to large
evergreen tree growing to 25-40 m tall, exceptionally to 65 m tall, and with a trunk diameter of up to 1.5 m. Thebark is thin and scaly, flaking off in small circular plates 5-10 cm across. The crown is narrow conic in young trees, becoming cylindric in older trees. The shoots are buff-brown to orange-brown, usually densely pubescent, and with prominent pulvini. The leaves are needle-like, 15-30 mm long, rhombic in cross-section, glaucous blue-green above with several thin lines ofstomata , and blue-white below with two broad bands of stomata.The cones are pendulous, slender cylindrical, 4-8 cm long and 1.5 cm broad when closed, opening to 3 cm broad. They have thin, flexible scales 15-20 mm long, with a wavy margin. They are reddish to dark purple, maturing pale brown 4-7 months after pollination. The
seed s are black, 2-3 mm long, with a slender, 5-8 mm long pale brown wing.Two geographical
subspecies (treated as varieties by some authors, and as distinct species by others) occur:
*"Picea engelmannii" subsp. "engelmannii" (Engelmann Spruce). All of the range except as below.
*"Picea engelmannii" subsp. "mexicana" (Mexican Spruce). Two isolated populations on high mountains in northernMexico , on the Sierra del Carmen inCoahuila (Sierra Madre Oriental ) and on Cerro Mohinora in Chihuahua (Sierra Madre Occidental ). Engelmann Spruces of theMadrean sky islands mountains in the extreme southeast of Arizona and southwest of New Mexico also probably belong to this subspecies, though this is disputed.Engelmann Spruce hybridises and intergrades extensively with the closely related
White Spruce found further north and east in the Rocky Mountains, and to a lesser extent with the closely relatedSitka Spruce where they meet on the western fringes of theCascades .Uses
Engelmann Spruce is of economic importance for its
wood , harvested forpaper -making and general construction. Wood from slow-grown trees at high altitude has a specialised use in making acousticguitar s andharp s. It is also used to a small extent as aChristmas tree .References and external links
*
* [http://www.conifers.org/pi/pic/engelmannii.htm Gymnosperm Database]
* [http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=233500909 Flora of North America]
* [http://www.pinetum.org/cones/PICEAcones.htm Arboretum de Villardebelle - photos of cones of "Picea engelmannii" and related spruces]
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