Brewer's Spruce
Encyclopedia
Picea breweriana is a species of spruce
native to western North America
, where it is one of the rarest on the continent, endemic to the Klamath Mountains
of southwest Oregon
and northwest California
. The specific epithet breweriana is in honor of William Henry Brewer
, the American botanist who collected it.
DNA analyses have shown that Picea breweriana has a basal
position in the Picea
clade
, suggesting that Picea originated in North America.
It grows at moderately high altitudes, from 1000–2700 m.
It is a large evergreen
coniferous
tree
growing to 20–40 m tall, exceptionally 54 m, and with a trunk diameter of up to 1.5 m. The bark
is thin and scaly, and purple-gray in color. The crown is very distinct, distinguished by level branches with vertically pendulous branchlets, each branch forming a 'curtain' of foliage. The pendulous foliage only develops when the tree grows to about 1.5–2 m tall; young trees smaller than this (up to about 10–20 years old) are open-crowned with sparse, level branchlets. The shoots are orange-brown, with dense short pubescence about 0.2 mm long and very rough with pulvini 1–2 mm long.
The leaves
are borne singly on the pulvini, and are needle-like, 15–35 mm long, flattened in cross-section, glossy dark green above, and with two bands of white stomata below.
The cones
are longer than most other North American spruces, pendulous, cylindrical, 8–15 cm long and 2 cm broad when closed, opening to 3–4 cm broad. They have smoothly rounded, thin, flexible scales 2 cm long. The immature cones are dark purple, maturing red-brown 5–7 months after pollination. The seed
s are black, 3–4 mm long, with a slender, 12–18 mm long pale brown wing.
Brewer's Spruce grows very slowly, typically less than 20–30 cm/year. It occurs mainly on ridgetop sites with very heavy winter snow
to provide a steady source of meltwater through the spring, but dry in the summer. The harsh ridgetop conditions minimize competition from other much faster-growing trees like Douglas-fir
. It is very well adapted to cope with heavy snow and ice loads, with tough branches, and the drooping branchlets shedding snow readily.
Outside of its native range, Brewer's Spruce is a highly valued ornamental tree in garden
s, particularly in northern Great Britain
and Scandinavia
, where it is appreciated for its dramatically pendulous foliage.
Spruce
A spruce is a tree of the genus Picea , a genus of about 35 species of coniferous evergreen trees in the Family Pinaceae, found in the northern temperate and boreal regions of the earth. Spruces are large trees, from tall when mature, and can be distinguished by their whorled branches and conical...
native to western North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
, where it is one of the rarest on the continent, endemic to the Klamath Mountains
Klamath Mountains
The Klamath Mountains, which include the Siskiyou, Marble, Scott, Trinity, Trinity Alps, Salmon, and northern Yolla-Bolly Mountains, are a rugged lightly populated mountain range in northwest California and southwest Oregon in the United States...
of southwest Oregon
Oregon
Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...
and northwest California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
. The specific epithet breweriana is in honor of William Henry Brewer
William Henry Brewer
William Henry Brewer was an American botanist. He worked on the first California Geological Survey and was the first Chair of Agriculture at Yale University's Sheffield Scientific School....
, the American botanist who collected it.
DNA analyses have shown that Picea breweriana has a basal
Basal (phylogenetics)
In phylogenetics, a basal clade is the earliest clade to branch in a larger clade; it appears at the base of a cladogram.A basal group forms an outgroup to the rest of the clade, such as in the following example:...
position in the Picea
Spruce
A spruce is a tree of the genus Picea , a genus of about 35 species of coniferous evergreen trees in the Family Pinaceae, found in the northern temperate and boreal regions of the earth. Spruces are large trees, from tall when mature, and can be distinguished by their whorled branches and conical...
clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...
, suggesting that Picea originated in North America.
It grows at moderately high altitudes, from 1000–2700 m.
It is a large evergreen
Evergreen
In botany, an evergreen plant is a plant that has leaves in all seasons. This contrasts with deciduous plants, which completely lose their foliage during the winter or dry season.There are many different kinds of evergreen plants, both trees and shrubs...
coniferous
Pinophyta
The conifers, division Pinophyta, also known as division Coniferophyta or Coniferae, are one of 13 or 14 division level taxa within the Kingdom Plantae. Pinophytes are gymnosperms. They are cone-bearing seed plants with vascular tissue; all extant conifers are woody plants, the great majority being...
tree
Tree
A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to...
growing to 20–40 m tall, exceptionally 54 m, and with a trunk diameter of up to 1.5 m. The bark
Bark
Bark is the outermost layers of stems and roots of woody plants. Plants with bark include trees, woody vines and shrubs. Bark refers to all the tissues outside of the vascular cambium and is a nontechnical term. It overlays the wood and consists of the inner bark and the outer bark. The inner...
is thin and scaly, and purple-gray in color. The crown is very distinct, distinguished by level branches with vertically pendulous branchlets, each branch forming a 'curtain' of foliage. The pendulous foliage only develops when the tree grows to about 1.5–2 m tall; young trees smaller than this (up to about 10–20 years old) are open-crowned with sparse, level branchlets. The shoots are orange-brown, with dense short pubescence about 0.2 mm long and very rough with pulvini 1–2 mm long.
The leaves
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....
are borne singly on the pulvini, and are needle-like, 15–35 mm long, flattened in cross-section, glossy dark green above, and with two bands of white stomata below.
The cones
Conifer cone
A cone is an organ on plants in the division Pinophyta that contains the reproductive structures. The familiar woody cone is the female cone, which produces seeds. The male cones, which produce pollen, are usually herbaceous and much less conspicuous even at full maturity...
are longer than most other North American spruces, pendulous, cylindrical, 8–15 cm long and 2 cm broad when closed, opening to 3–4 cm broad. They have smoothly rounded, thin, flexible scales 2 cm long. The immature cones are dark purple, maturing red-brown 5–7 months after pollination. The seed
Seed
A seed is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant...
s are black, 3–4 mm long, with a slender, 12–18 mm long pale brown wing.
Brewer's Spruce grows very slowly, typically less than 20–30 cm/year. It occurs mainly on ridgetop sites with very heavy winter snow
Snow
Snow is a form of precipitation within the Earth's atmosphere in the form of crystalline water ice, consisting of a multitude of snowflakes that fall from clouds. Since snow is composed of small ice particles, it is a granular material. It has an open and therefore soft structure, unless packed by...
to provide a steady source of meltwater through the spring, but dry in the summer. The harsh ridgetop conditions minimize competition from other much faster-growing trees like Douglas-fir
Douglas-fir
Douglas-fir is one of the English common names for evergreen coniferous trees of the genus Pseudotsuga in the family Pinaceae. Other common names include Douglas tree, and Oregon pine. There are five species, two in western North America, one in Mexico, and two in eastern Asia...
. It is very well adapted to cope with heavy snow and ice loads, with tough branches, and the drooping branchlets shedding snow readily.
Outside of its native range, Brewer's Spruce is a highly valued ornamental tree in garden
Garden
A garden is a planned space, usually outdoors, set aside for the display, cultivation, and enjoyment of plants and other forms of nature. The garden can incorporate both natural and man-made materials. The most common form today is known as a residential garden, but the term garden has...
s, particularly in northern Great Britain
Great Britain
Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...
and Scandinavia
Scandinavia
Scandinavia is a cultural, historical and ethno-linguistic region in northern Europe that includes the three kingdoms of Denmark, Norway and Sweden, characterized by their common ethno-cultural heritage and language. Modern Norway and Sweden proper are situated on the Scandinavian Peninsula,...
, where it is appreciated for its dramatically pendulous foliage.
External links
- ITIS * North America: Picea breweriana
- NCBI Taxonomy: Picea breweriana
- GRIN Taxonomy: Picea breweriana
- Catalogue of Life: Picea breweriana
- Flora of North America: Picea breweriana
- Jepson Manual Treatment of Picea breweriana
- USDA Plants Profile of Picea breweriana
- Picea breweriana on Conifer Country
- Photo gallery of Picea breweriana