自然保护与休闲部保护·守护·共享
自然保护与休闲部
目录北方硬木森林
该组的植被由弗吉尼亚州西部高海拔地区 (> 900米 [ 3 , 000英尺]) 的混合硬木森林组成。南阿巴拉契亚山脉的例子包括北卡罗来纳州和田纳西州的高海拔地区，以及弗吉尼亚州西南部和肯塔基州东部。中部阿巴拉契亚山脉的例子包括从弗吉尼亚州西南部向北延伸至阿勒格尼山脉高地以及宾夕法尼亚州北部和纽约州南部未受冰川侵蚀的阿勒格尼高原。
Northern Hardwood Forest communities have distinct regional variation and floristic composition at a given site varies with geography and specific site conditions. Southern Appalachian Northern Hardwood Forests are prevalent throughout the high-elevation Mount Rogers-Whitetop Mountain (Balsam Mountains) area of the Southern Blue Ridge (Grayson, Smyth, and Washington Counties), with more local outliers at the highest elevations of the Iron Mountains (Grayson and Smyth Counties), Clinch Mountain (Russell, Smyth, Tazewell, and Washington Counties), and Black Mountain (Wise County) on the Kentucky border. Co-dominant trees in Southern Appalachian stands are sugar maple (Acer saccharum, American beech (Fagus grandifolia), yellow birch (Betula alleghaniensis), and yellow buckeye (Aesculus flava) in variable proportions. Fraser magnolia (Magnolia fraseri), eastern hemlock (Tsuga canadensis), and red spruce (Picea rubens) are important associate trees in some stands, particularly in the Mount Rogers - Whitetop area. Sapling sugar maple, striped maple (Acer pensylvanicum) and mountain maple (Acer spicatum) are common understory species. Smooth blackberry (Rubus canadensis) and hobblebush (Viburnum lantanoides) are common shrubs. Herb layers are moderately sparse to moderately dense, with graminoid-rich patches tending to occur on the drier slope convexities. Some of the most abundant herbs in the Southern Appalachian Northern Hardwood Forests are Appalachian white snakeroot (Ageratina altissima var. roanensis), southern lady fern (Athyrium asplenioides), evergreen wood fern (Dryopteris intermedia), mountain wood aster (Eurybia chlorolepis), sweet white violet (Viola blanda), and Appalachian woodland sedge (Carex austrolucorum).
Northern Hardwood stands in the Central Appalachians occur extensively at high elevations (>900 m [3,000 ft]) of Allegheny Mountain in Highland County, with smaller-patch outliers occurring on north-facing slopes over 1,070 m (3,500 ft) in the Blue Ridge, Ridge and Valley, and Cumberland Mountains, south to Tazewell, Russell, and Wise Counties. These are dominated by sugar maple, black cherry (Prunus serotina var. serotina), yellow birch, northern red oak (Quercus rubra), red maple (Acer rubrum), and sweet birch (Betula lenta var. lenta), while American beech, and eastern hemlock are less frequent co-dominants. Overstory composition varies occasionally to nearly pure sugar maple. Striped maple, mountain maple, and mountain holly (Ilex montana) are the chief understory species, along with sapling sugar maple and beech. The herb layers of many stands are characterized by patch-dominance of hayscented fern (Dennstaedtia punctilobula). Other more or less characteristic herbaceous species include whorled wood aster (Oclemena acuminata), evergreen wood fern (Dryopteris intermedia), prickly tree-clubmoss (Dendrolycopodium dendroideum, stiff clubmoss (Spinulum annotinum), tall millet grass (Milium effusum var. cisatlanticum), grove bluegrass (Poa alsodes), northern shorthusk (Brachyelytrum aristosum), purple oat grass (Schizachne purpurascens), sedges (particularly Carex appalachica, Carex flexuosa, Carex digitalis, Carex leptonervia, and Carex woodii), eastern rose mandarin (Streptopus lanceolatus), and sweet white violet (Viola blanda). The importance of red maple, sweet birch, northern red oak, and black cherry in contemporary Central Appalachian examples of this community group reflects secondary succession following catastrophic logging and fire disturbances in the early part of the twentieth century. Sugar maple and beech, both abundant in understory layers and locally co-dominant in the overstory, appear positioned to assume dominance as current secondary stands mature. However, beech-bark disease and excessive deer browsing are serious threats to the future viability of the largest stands on Allegheny Mountain .
在弗吉尼亚州，几种北方鸣禽，包括棕色爬行鸟（ Certhia americana ）、哀悼莺（ Oporornis philadelphia ）和黄腹吸汁啄木鸟（ Sphyrapicus varius ），仅在北部硬木森林中繁殖。
参考文献：Adams 等。等。（ 2003 ）、Coulling 和 Rawinski（ 1999 ）、Fleming 和 Coulling（ 2001 ）、Fleming 和 Moorhead（ 1996 ）、Rawinski 等人。( 1996 )、莱茵哈特和韦尔 ( 1984 )。
© DCR-DNH，加里·P·弗莱明。
弗吉尼亚州已对北部硬木森林进行了充分的采样，特别是在南蓝岭的罗杰斯山-怀特托普地区和高地县的阿勒格尼山。到目前为止，已在18县对79此类地块进行了采样（图1 ），尽管某些分类单元比其他单元更能得到地块数据的支持。然而，额外的采样不太可能改变这些单位的基本概念。单击下面任何突出显示的 CEGL 代码即可查看NatureServe Explorer 提供的全球 USNVC 描述。
下载下面列出的每个社区类型的组成汇总统计电子表格。
