Picea pungens is a species of
spruceA 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 AmericaNorth 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...
, from southeast
IdahoIdaho is a state in the Rocky Mountain area of the United States. The state's largest city and capital is Boise. Residents are called "Idahoans". Idaho was admitted to the Union on July 3, 1890, as the 43rd state....
and southwest
WyomingWyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...
, south through
UtahUtah is a state in the Western United States. It was the 45th state to join the Union, on January 4, 1896. Approximately 80% of Utah's 2,763,885 people live along the Wasatch Front, centering on Salt Lake City. This leaves vast expanses of the state nearly uninhabited, making the population the...
and
ColoradoColorado is a U.S. state that encompasses much of the Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains...
to
ArizonaArizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...
and
New MexicoNew Mexico is a state located in the southwest and western regions of the United States. New Mexico is also usually considered one of the Mountain States. With a population density of 16 per square mile, New Mexico is the sixth-most sparsely inhabited U.S...
. It grows at high altitudes from 1750 metre altitude, though unlike
Engelmann SprucePicea engelmannii is a species of spruce native to western North America, from central British Columbia and southwest Alberta, southwest to northern California and southeast to Arizona and New Mexico; there are also two isolated populations in northern Mexico...
in the same area, it does not reach the
alpine tree-lineThe tree line is the edge of the habitat at which trees are capable of growing. Beyond the tree line, they are unable to grow because of inappropriate environmental conditions...
. It is most commonly found growing along stream sides in mountain valleys, where moisture levels in the soil are greater than the often low rainfall in the area would suggest.
Description
Blue spruce is a medium-sized
evergreenIn 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...
treeA 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 25 – tall, exceptionally to 46 m (150.9 ft) tall, and with a trunk diameter of up to 1.5 m (4.9 ft). The
barkBark 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 gray, with narrow vertical furrows. The crown is conic in young trees, becoming cylindric in older trees. The shoots are stout, orange-brown, usually glabrous, and with prominent pulvini.
The
leavesA 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 needle-like, 15 – long, stout, rhombic in cross-section, dull gray-green to bright glaucous blue (very variable from tree to tree in wild populations), with several lines of stomata; the tip is viciously sharp.
The
conesA 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 pendulous, slender cylindrical, 6 – long and 2 cm (0.78740157480315 in) broad when closed, opening to 4 cm (1.6 in) broad. They have thin, flexible scales 20 – long, with a wavy margin. They are reddish to violet, maturing pale brown 5–7 months after pollination. The
seedA 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 – long, with a slender, 10 – long pale brown wing.
Distribution and habitat
Native and widely occurring in the montane zone of the central and southern Rocky Mountains. Commonly planted as an ornamental.
Subspecies and hybrids
Blue spruce does not normally hybridize with other spruces, though hybrids with Engelmann Spruce have been found very rarely.
External links