yellow and paper birches, Betula allegheniensis and
B. papyrifera; sugar maple, Acer saccharum; American
beech, Fagus grandifolia; eastern white pine, Pinus
strobus; eastern hemlock, Tsuga canadensis; and
mountain ash, Sorbus americana. In low lying bogs
of the northeastern United States and adjoining
Canada, red spruce occurs in association with black
spruce, ,Picea mariana, with which it readily
hybridizes, and eastern larch, Larix occidentalis.
In North Carolina, Tennessee, and southwestern
Virginia, balsam fir is replaced by Fraser fir, A.
fraseri, and in West Virginia, Abies sp. is not
commonly associated with red spruce. Red spruce is
a shade tolerant tree which is a component of
several climax vegetation communities (Fowells
1965) .
Extensive areas of forest where red spruce is a
major component are largely unmanaged and relatively
inaccessible. These forests have been historically
subjected to a wide range of damaging agents
including insects, fungi, fire, wind, and ice.
Widespread outbreaks of spruce budworm,
Choristoneura fumiferana, and several species of
bark beetles; Dendroctonus rufipennis and
Polygraphus rufipennis, have been reported since the
late 1800’s (Kucera and Taylor 1984; Hopkins 1899;
Hopkins 1901). In North Carolina, Tennessee, and
southwestern Virginia, the introduced adelgid,
Adelges piceae, has caused catastrophic mortality of
A. fraseri since the late 1950's (Lambert and Ciesla
1966) . A root pathogen, Armillaria sp., is known to
cause tree mortality in red spruce and the dwarf
mistletoe, Arceuthobium pusilum, has recently been
found causing damage to this tree (Hawksworth and
Shigo 1980). High winds, especially on the mountain
peaks, have caused extensive blowdown in these
forests. Red spruce, a shallow rooted tree, is
highly susceptible to blowdown.
Red spruce is an important sawtimber and pulpwood
species. The tree is also a major forest component
in many places of high scenic or recreational value
and contributes significantly to the unique
character of these areas. Red spruce regeneration
provides critical habitat for certain wildlife
species such as the snowshoe hare.
Figure 2 - Declining red spruce on the Monongahela
National Forest, West Virginia.
4 INVENTORIES OF SPRUCE AND FIR DECLINE
Beginning in 1984, a series of special Inventories
were conducted by the Forest Pest Management
organization of the USDA Forest Service to obtain
data on the status of decline and mortality of red
spruce and its most closely associated species,
balsam and Fraser fir. The objectives of these
inventories were to:
1. Identify and classify forests with a red spruce
component into specified mortality classes.
2. Obtain data on levels of decline and mortality
of spruce and fir in each mortality class.
3 SYMPTOMS OF RED SPRUCE DECLINE
A variety of symptoms associated with a decline of
red spruce has been reported in recent years. In
portions of the northeastern United States, the
predominant symptom associated with the decline of
red spruce is a reddening of the current years
growth, a condition commonly known as winter damage.
Successive episodes of winter damage causes branches
to die from the tops down and from the tips of the
branches inward (Friedland et al. 1984). In West
Virginia, decline of sawtimber size trees is
characterized by mortality of the branches
throughout the crown (Fig. 2). The fungus Valsa
(=Cytospora) kunzei has been isolated from affected
branches. This fungus is normally considered a
secondary pathogen and its overall role in the
decline syndrome is not yet fully understood (Mielke
et al. 1986). In North Carolina and Tennessee,
decline of red spruce is characterized by a loss of
older foliage.
In addition, a general decline of the growth of
red spruce has been documented throughout much of
its natural range, beginning in the early 1960's
(Adams et al. 1985; Hornbeck and Smith 1985).
These symptoms occur amid a high incidence of
damage and mortality to both spruce and fir, caused
by the biotic and climatic agents described in the
preceding section.
3. Map the location of forests with a red spruce
component by specified mortality classes.
4. Evaluate the condition of spruce and fir re
generation.
5. Identify biotic, climatic and mechanical fac
tors associated with the decline and mortality of
red spruce.
6. Establish a data base against which results of
future surveys can be compared.
To date inventories have been conducted in three
major portions of the natural range of red spruce.
These are in various stages of completion. Survey
areas included (1) portions of three northeastern
states; New Hampshire, New York, and Vermont; (2)
the high elevation forests of West Virginia; (3) and
the red spruce-Fraser fir forests which occupy the
crests of the highest mountains in western North
Carolina, eastern Tennessee, and southwestern
Virginia. Maine and adjoining portions of northern
New Hampshire and Vermont also contain extensive
areas of spruce-fir forest. These areas have not
been included in these inventories because they have
recently suffered from widespread defoliation by C.
fumiferana, which is known to cause tree mortality,
top dieback, and growth reduction in both spruce and
fir in that portion of the natural range of red
spruce (Kucera and Taylor 1984).
