Associated Forest Cover
Pure stands of red spruce comprise the forest cover type Red Spruce (Society of American Foresters Type 32). Red spruce is also a major component in 5 and a minor component in 13 other forest cover types (10):
5 Balsam Fir
12 Black Spruce
17 Pin Cherry
18 Paper Birch
21 Eastern White Pine
22 White Pine-Hemlock
23 Eastern Hemlock
25 Sugar Maple-Beech-Yellow Birch
30 Red Spruce-Yellow Birch
31 Red Spruce-Sugar Maple-Beech
33 Red Spruce-Balsam Fir
34 Red Spruce-Fraser Fir
35 Paper Birch-Red Spruce-Balsam Fir
37 Northern White-Cedar
60 Beech-Sugar Maple
107 White Spruce
108 Red Maple
Some of the shrubs associated with red spruce are: blueberry (Vaccinium spp.), hobblebush (Viburnum lantanoides), witherod (V. cassinoides), rhodora (Rhododendron canadense), lambkill (Kalmia angustifolia), mountain-holly (Nemopanthus mucronata), speckled alder (Alnus rugosa), red raspberry (Rubus idaeus var. strigosus), creeping snowberry (Gaultheria hispidula), wintergreen (G. procumbens), fly honeysuckle (Lonicera canadensis), gooseberry (Ribes spp.), witch-hazel (Hamamelis virginiana), downey serviceberry (Amelanchier arborea), beaked hazel (Corylus cornuta), and Canada yew (Taxus canadensis).
A number of mosses and herbs are also found growing in red spruce forest types. Certain mosses, herbs, and shrubs, however, have been shown to be related to site quality of red spruce (22). The three main associations, Hylocomium/Oxalis, Oxalis/Cornus, and Viburnum/0xalis, in that order, indicate increasing site productivity and increasing hardwood competition. Similar site types in the higher elevations of the Appalachian Mountains of North
Carolina include Hylocomium/Oxalis on north-facing slopes above 1520 m (5,000 ft), Oxalis/Dryopteris at high elevations and all exposures, and the best site type for red spruce and Fraser fir, Viburnum/Vaccinium/Dryopteris (47).
The Oxalis/Cornus association is considered the best for growing conditions in the northern part of the range. On these sites the soil is rich enough for red spruce but not fertile enough for the tolerant hardwoods to offer serious competition (22).