MediaWiki default at 08:34, 27 April 2007

2007-04-27T08:34:20Z

New page

:''For places named after the oak, see [[Burr Oak]].''
{{Taxobox
| color = lightgreen
| name = Bur Oak
| status = LR/lc
| image = Quercus macrocarpa USDA.jpg
| image_width = 240px
| image_caption = Bur Oak leaves and acorn
| regnum = [[Plant]]ae
| divisio = [[flowering plant|Magnoliophyta]]
| classis = [[dicotyledon|Magnoliopsida]]
| ordo = [[Fagales]]
| familia = [[Fagaceae]]
| genus = ''[[oak|Quercus]]''
| species = '''''Q. macrocarpa'''''
| binomial = ''Quercus macrocarpa''
| binomial_authority = [[André Michaux|Michx.]]
}}

The '''Bur Oak''', (''Quercus macrocarpa''), sometimes spelled '''Burr Oak''', is a species of [[oak]] in the [[List of Quercus species#Section Quercus|white oak section]] ''Quercus'' sect. ''Quercus'', native to [[North America]] in the eastern and midwestern [[United States]] and south-central [[Canada]]. This plant is also called '''Mossycup oak''' and '''Mossycup white oak'''. It occurs from the [[Appalachian Mountains]] west to the middle of the [[Great Plains]], extending to central [[Texas]], across southernmost [[Manitoba]], [[Ontario]] and [[Quebec]], east to the [[Atlantic (ocean)|Atlantic]] Coast in southern [[New Brunswick]], and down the coast to [[Delaware]].

It is a large [[deciduous]] [[tree]] growing up to 30 [[metre|m]], rarely 37 m, in height, and is one the most massive oaks with a trunk diameter of up to 3 m; reports of taller trees occur, but have not been verified. It is also one of fastest-growing oaks, with [[growth rate]]s of 60-100 cm per year when young. It commonly lives to be 200 to 300 years old, and may become significantly older. The [[bark]] is a medium gray and somewhat rugged.

[[Image:Quercus macrocarpa.jpg|left|thumb|Acorns]]
The [[leaf|leaves]] are 7-15 cm long and 5-13 cm broad, variable in shape, with a lobed margin. Most often, the basal 60% is narrower and deeply lobed, while the apical 40% is wider and has shallow lobes or large teeth. The [[flower]]s are greenish-yellow [[catkin]]s, produced in the spring. The [[acorn]]s are very large, 2-5 cm long and 2-4 cm broad, with a large cup that wraps much of the way around the nut, with large overlapping scales and often a fringe at the edge of the cup.

Bur Oak is sometimes confused with [[Overcup oak]] and [[White oak]].

===Ecology===
Bur Oak typically grows in the open, away from [[forest]] canopy. For this reason, it is an important tree on the eastern [[prairie]]s, where it is often found near [[waterway]]s in more forested areas, where there is a break in the canopy. It is also a fire-resistant tree, and possesses significant [[drought]] resistance by virtue of a long [[taproot]]. New trees may, after two to three years of growth, possess a 1-2 m deep taproot. The [[West Virginia]] state champion Bur Oak has a [[trunk]] [[diameter]] of almost 3 m (9 feet).

The acorns are the largest of any North American oak, and are an important [[wildlife]] food; [[American Black Bear]]s sometimes tear off branches to get them. However, heavy nut crops are borne only every few years. In this strategy, known as masting, the large seed crop every few years overwhelms the ability of seed predators to eat the acorns, thus ensuring the survival of some seeds. Other wildlife, such as [[deer]] and [[porcupine]], eat the leaves, twigs and bark. [[Cattle]] are heavy browsers in some areas.

===Cultivation and uses===
Bur Oak makes an outstanding [[ornamental tree]]. It is one of the most tolerant of [[urban area|urban]] conditions of the white oaks, and has been planted in many places such as [[Anchorage, Alaska|Anchorage]], [[Alaska]] and [[San Antonio]], [[Texas]]. It withstands [[chinook wind|chinook]] conditions at [[Calgary]], [[Alberta]].

The [[wood]] is high quality, and is almost always marketed as "white oak".

The name sometimes is spelled "burr oak", as for example in [[Burr Oak State Park]] in [[Ohio]], the city of [[Burr Oak, Kansas]], the village of [[Burr Oak, Michigan]], and in the title ''Burr Oaks'' by poet [[Richard Eberhart]].

It is also less commonly called "burl oak," as in the Burl Oaks Country Club in [[Mound, Minnesota]], and the [[Burl-Oak Theatre Company]] in [[Oakville, Ontario]]

==References==
{{commons|Quercus macrocarpa}}
* {{IUCN2006|assessors=Sternberg, G.|year=1998|id=33991|title=Quercus macrocarpa|downloaded=06 May 2006}}
*[http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=233501058 Flora of North America: ''Quercus macrocarpa'']
*[http://plants.usda.gov/java/profile?symbol=QUMA2 USDA Plants Profile: ''Quercus macrocarpa'']
*[http://www.cas.vanderbilt.edu/bioimages/species/frame/quma2.htm ''Quercus macrocarpa'' images at bioimages.vanderbilt.edu]

[[Category:Fagaceae|Oak, Bur]]
[[Category:Trees of Plains-Midwest U.S.|Oak, Bur]]
[[Category:Trees of Northeastern United States|Oak, Bur]]
[[Category:Trees of Southeastern Canada|Oak, Bur]]
[[Category:Trees of Manitoba|Oak, Bur]]
[[Category:Trees of Saskatchewan|Oak, Bur]]

Bur oak - Revision history

MediaWiki default at 08:34, 27 April 2007