Brewer Spruce

Brewer spruce
weeping spruce

More info for the term: presence

Brewer spruce is a native, endemic conifer. It has a distinctive,
drooping appearance caused by the presence of thousands of long,
ropelike branches hanging from all but the topmost horizontal limbs
[14,18,19,23]. At maturity, Brewer spruces usually reaches 80 to 100
feet (24-30 m) in height [16], but can reach up to 172 feet (52 m) in
height [21]. Diameters range from approximately 3.8 feet (117 cm) [18]
to up to 4.5 feet (1.35 m) in some areas [21]. The bark is thin and
broken into long, thin, appressed scales [14,16].

The leaves are obtuse, flat on top, and rounded underneath, and spread
from all sides of the branchlets. The male cones are stalked and oblong
(3 to 4 inches [7-10 cm] long). The seeds are 0.12 inch (3 mm) long
[14,16].

The root system generally is shallow; however, on deeper soils, a few
vertical roots may extend several meters [18].

Brewer spruce can live as long as 900 years [21].

Brewer spruce is endemic to the Klamath region of northwestern
California and adjacent Oregon. It is distributed from from Del Norte,
Trinity, and Siskiyou counties in California to Curry and Josephine
counties in Oregon [11,14,18]. The best developed stands are located
on high ridges and upper valleys of the Klamath, Shasta-Trinity, and Six
Rivers National Forests of California and in the Siskiyou and Rogue
River National Forests of Oregon [11,18,20].

More info for the term: fire regime

Brewer spruce is not fire resistant; the thin bark, drooping nature of
the branches, and shallow root system make it sensitive to fire
[17,18,23]. Fire sensitivity appears to have limited the range of
Brewer spruce [18]; it is largely confined to fire-resistant open
forests on north-facing slopes or rocky ridges [17,23].

FIRE REGIMES :
Find fire regime information for the plant communities in which this
species may occur by entering the species name in the FEIS home page under
"Find FIRE REGIMES".

More info for the term: fuel

Brewer spruce serves as a medium fuel type [2].

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More info for the term: phanerophyte

Phanerophyte

More info for the terms: association, herbaceous, serpentine soils, shrubs

Despite its restricted distribution, Brewer spruce has a broad
ecological amplitude. Its apparent limitations are high water tables
and frequent fires [17,18]. Brewer spruce is quite tolerant of soil
moisture stress, cold temperatures, low light, low-fertility soils, and
snow [13,18,21]. Although Brewer spruce can tolerate considerable soil
moisture stress, it is sensitive to high evaporation demands. Under
such demand, stomata close, halting photosynthesis [13,18,21].

Brewer spruce grows in a climate of cold, wet winters and warm,
relatively dry summers with respective temperature ranges of 30 to 41
degrees Fahrenheit (-1 to 5 deg C) and 52 to 68 degrees Fahrenheit
(11-20 deg C). Annual precipitation varies between 39 and 110 inches
(1,000-2,800 mm) [18].

Brewer spruce stands occur on north-, south-, east-, and west-facing
slopes, but the preferred habitat is steep, north-facing slopes [3,18].
Brewer spruce occurs on rocky ridges [18], cold hollows [14], and on dry
talus and moraines [17]. It never occurs in areas where the
soils are saturated during the growing season, such as boggy or wet
areas. The slope is generally 11 to 70 percent [18].

Brewer spruce grows on soils developed from sedimentary, granitic,
serpentine, and metavolcanic rock [18]. Most soils are shallow, rocky,
and undeveloped; however, Brewer spruce does occur on deeper soils [18].
Soil pH ranges between 4.6 and 7.2 on mica schist, meta volcanic,
granitic, and ultrabasic soils [21]. Soil depth varies between 12 and
50 inches (6.5-127 cm) [3]. Kruckeberg [9] lists Brewer spruce as an
indicator of serpentine soils. Heavy metals, especially iron and
nickel, can attain high levels in soil and plant tissues of Brewer
spruce [9].

Brewer spruce occurs at the elevations listed below [3,18]:

feet meters
Siskiyou Region 3,840-5,120 1,163-1,515
Eastern Klamath Region 4,500-7,500 1,370-2,290

The majority of Brewer spruce overstory associates are listed in the
Distribution and Occurrence frame. Other overstory associates not
mentioned previously include noble fir (Abies procera), sugar pine
(Pinus lambertina), Pacific yew (Taxus brevifolia), and Alaska cedar
(Chamaecyparis nootkatensis) [3,4,8,17,18]. Shrubs that occur in
association with Brewer spruce include Sadler oak, huckleberry oak
(Quercus vaccinifolia), greenleaf manzanita (Arctostaphylos patula),
pinemat manzanita (A. nevadensis), thinleaf huckleberry (Vaccinium
membranaceum), snowberry (Symphoricarpos hesperius), dwarf Oregon grape
(Berberis nervosa), and Labrador tea (Ledum glandulosum) [3,17,18].
Associates that occur in the herbaceous layer are beargrass (Xerophyllum
tenax), western prince's pine (Chimaphila umbellata), vanillaleaf
(Achlys triphylla), rattlesnake plantain (Goodyera oblongifolia),
Pacific trillium (Trillium ovatum), false Solomon's seal (Smilacina
stellata), queenscup (Clintonia uniflora), starflower (Tridentalis
latifolia), and groundsel (Senecio triangularis) [3,4,17,18].

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This species is known to occur in association with the following cover types (as classified by the Society of American Foresters):

205 Mountain hemlock
206 Engelmann spruce - subalpine fir
207 Red fir
211 White fir
215 Western white pine
224 Western hemlock
229 Pacific Douglas-fir
231 Port-Orford-cedar
234 Douglas-fir - tanoak - Pacific madrone
243 Sierra Nevada mixed conifer
244 Pacific ponderosa pine - Douglas-fir
247 Jeffrey pine
256 California mixed subalpine

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This species is known to occur in the following ecosystem types (as named by the U.S. Forest Service in their Forest and Range Ecosystem [FRES] Type classification):

FRES20 Douglas-fir
FRES21 Ponderosa pine
FRES23 Fir - spruce
FRES24 Hemlock - Sitka spruce

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This species is known to occur in association with the following plant community types (as classified by Küchler 1964):

More info for the term: forest

K001 Spruce - cedar - hemlock forest
K004 Fir - hemlock forest
K005 Mixed conifer forest
K007 Red fir forest
K012 Douglas-fir forest
K029 California mixed evergreen forest

More info for the term: series

In a series of fires in 1987 that burned throughout the range of Brewer
spruce, low-intensity surface fires killed Brewer spruce in mixed
stands. In small stands on north, rocky slopes, Brewer spruce was
undamaged [18]. On granitic soils fire can be extremely damaging to
Brewer spruce because the shallow root system is damaged by heat
transfer to the soil [3].

Brewer spruce provides excellent wildlife habitat [4]. Cones and seeds
of Brewer spruce do not appear to be a preferred food for rodents [18].

More info for the terms: climax, codominant

Although Brewer spruce grows throughout the Klamath region, it usually
occurs in local, disjunct populations [17]. It is a minor component of
a variety of communities [24]. In some areas, Brewer spruce is a minor
climax species in stands dominated by California red fir (Abies
magnifica), white fir (A. concolor), or mountain hemlock (Tsuga
mertenmsiana) [3]. It occurs occasionally as a codominant in some
California red fir and western hemlock habitat types. Near the Russian
Peak area of the Marble Mountains of California, Brewer spruce is a
major component of the California red fir/northern twinflower (Linnaea
borealis) and California ref fir/huckleberry oak (Quercus vaccinifolia)
types [17]. This species also occurs in small dense stands on mostly
north-facing slopes, as individuals invading seral pine stands and
montane chaparral, and as scattered individuals in closed white fir
forests [17]. Brewer spruce is often an indicator of cold and wet
environments [2].

Brewer spruce is listed as a dominant or codominant overstory species in
the following published classification:

Preliminary plant associations of the Siskiyou Mountain Province [3].

More info for the term: tree

Tree

More info for the terms: basal area, mesic, natural, presence, seed

Brewer spruce is best managed on mesic sites that are characterized by
the presence of Sadler oak (Quercus sadleriana). Brewer spruce growth
is best in mixed stands with uneven-aged management [18]. Natural
regeneration of Brewer spruce is good under dense white fir-Brewer
spruce stands, but it does not regenrate as well in open conditions [3].

Little information on volume or yield of Brewer spruce is available.
The average total basal area of a few sampled stands is 205 square feet
per acre (47 sq m/ha), with an annual increment of 9 square feet per
acre (2 sq m/ha) [18].

Artificial propagation is best from seed. Some spruce seeds have been
stored without loss of viability for periods of 5 to 17 years [16].
Safford [26] describes methods of seed extraction and storage and
nursery practice.

Cooley spruce gall adelgid (Adelges cooleyi) is common in Brewer spruce
but does little harm. Seed chalcids (Megastigmus spp.) have been
observed in mature seeds of Brewer spruce. Parasitism by dwarf
mistletoe (Arceuthobium campylopodum) has been observed in 36 percent of
local populations. Brewer spruce is more susceptible to windthrow than
its associates because of its shallow root system. Shallow roots also
result in high incidences of root rot (Heterobasision annosum) in some
areas [18].

CA OR

In Europe, Brewer spruce is considered a popular ornamental [18].

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More info for the term: tree

Strobilus buds appear in early summer, accompanied by the shedding of
pollen, at which time the conelets are receptive. The male strobili
develop from axils of needles of the previous year's shoots. After
pollenation, the strobili dry and fall from the tree and the conelets
turn down and mature over the summer, into September and October.
Dissemination follows immediately [18].

Brewer spruce recovery from fire is generally slow. Seedlings are
unable to survive strong sunlight and are intolerant of moisture stress
[18]. The recovery of Brewer spruce from the extensive fires of 1987
may take decades or centuries [18]. Atzet and Wheeler [2], however,
reported that light fires may stimulate seeding or germination of Brewer
spruce.

More info for the terms: root crown, secondary colonizer

Tree without adventitious-bud root crown
Secondary colonizer - off-site seed

More info for the terms: epigeal, forest, litter, monoecious, seed, stratification

The major regeneration mode of Brewer spruce is by seed [2]. Brewer
spruce is monoecious and begins producing seed at 20 to 30 years of age.
Mature Brewer spruce are apparently fair seed producers [18]. Crops
occur at 2-year intervals, but some trees produce cones yearly [18].
Production of seed ranges between 51,000 and 74,000 seeds per pound
(112,500-163,000 seeds/kg) [18], with a reported average of 61,000 seeds
per pound (134,500 seeds/kg) [16]. Seeds of Brewer spruce require a
stratification period of 30 to 90 days [14,16]. Germinations rates vary
from 50 to 96 percent, with an average of 88 percent [16,18].

Germination is epigeal and occurs on loose soil from upturned roots,
decaying logs, forest humus, and leaf litter under brushfields.
Seedlings are unable to survive strong sunlight and are sensitive to
high moisture stress and temperatures of exposed sites. First season
epicotyl height growth is less than 0.24 inch (6 mm). Further growth is
slow, but it appears to be faster on south-facing montane chaparral
[18]. Saplings and pole-sized Brewer spruce average 6 inches (0.15 m)
in annual height growth [18].

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This species can be found in the following regions of the western United States (according to the Bureau of Land Management classification of Physiographic Regions of the western United States):

1 Northern Pacific Border
4 Sierra Mountains

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More info for the terms: climax, competition

Brewer spruce is very shade tolerant and can become established under an
almost closed canopy [18,21]. It is usually occurs in late seral or
climax communities but can also invades seral pine stands and montane
chaparral [17,21]. Toward the eastern limit of its range, stands
dominated by western white pine (Pinus monticola) and Douglas-fir
(Pseudotsuga menziesii) are replace by Brewer spruce-Shasta red fir
(Abies magnifica var. shastensis) climax [21]. Brewer spruce is
restricted to less fertile soils because of strong competition from
other conifers [18,21].

The currently accepted scientific name of Brewer spruce is Picea
breweriana Wats. [14,18,19]. There are no recognized subspecies or
varieties. Brewer spruce grows adjacent to Engelmann spruce (Picea
engelmannii), but no hybridization between the two has been observed
[18].

The wood of Brewer spruce is soft, heavy, and close grained [14]. The
branching habit of Brewer spruce results in the wood having many knots,
and it has little commercial value. Trees that are harvested are often
mixed with other trees for use as low grade lumber [18].