A spruce is a tree of the genus ''Picea'' (), a genus of about 35 species of

conifer Conifers are a group of conifer cone, cone-bearing Spermatophyte, seed plants, a subset of gymnosperms. Scientifically, they make up the phylum, division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single ...

ous evergreen trees in the family Pinaceae, found in the northern temperate and

boreal Boreal may refer to: Climatology and geography *Boreal (age), the first climatic phase of the Blytt-Sernander sequence of northern Europe, during the Holocene epoch *Boreal climate, a climate characterized by long winters and short, cool to mild ...

( taiga) regions of the Earth. ''Picea'' is the sole genus in the

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end subfamily botanical names with "-oideae", and zoologi ...

Piceoideae. Spruces are large trees, from about 20 to 60 m (about 60–200 ft) tall when mature, and have whorled branches and

conical A cone is a three-dimensional geometric shape that tapers smoothly from a flat base (frequently, though not necessarily, circular) to a point called the apex or vertex. A cone is formed by a set of line segments, half-lines, or lines conn ...

form. They can be distinguished from other members of the pine family by their needles (leaves), which are four-sided and attached singly to small persistent peg-like structures ( pulvini or sterigmata) on the branches, and by their cones (without any protruding

bract In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves. They may be smaller, larger, or of ...

s), which hang downwards after they are pollinated. The needles are shed when 4–10 years old, leaving the branches rough with the retained pegs. In other similar genera, the branches are fairly smooth. Spruce are used as

food plants A crop is a plant that can be grown and harvested extensively for profit or subsistence. When the plants of the same kind are cultivated at one place on a large scale, it is called a crop. Most crops are cultivated in agriculture or hydroponics ...

by the larvae of some

Lepidoptera Lepidoptera ( ) is an order (biology), order of insects that includes butterfly, butterflies and moths (both are called lepidopterans). About 180,000 species of the Lepidoptera are described, in 126 Family (biology), families and 46 Taxonomic r ...

(moth and butterfly) species, such as the eastern spruce budworm. They are also used by the larvae of

gall adelgid The gall adelgid (''Adelges cooleyi'') is an adelgid species that produces galls in spruce trees. They infect the new buds of native spruce trees in the foothills of the Rocky Mountains in the spring. They also attack blue spruce to a lesser de ...

s (''Adelges'' species). In the mountains of western

Sweden Sweden, formally the Kingdom of Sweden,The United Nations Group of Experts on Geographical Names states that the country's formal name is the Kingdom of SwedenUNGEGN World Geographical Names, Sweden./ref> is a Nordic country located on ...

, scientists have found a

Norway spruce ''Picea abies'', the Norway spruce or European spruce, is a species of spruce native to Northern, Central and Eastern Europe. It has branchlets that typically hang downwards, and the largest cones of any spruce, 9–17 cm long. It is very close ...

, nicknamed Old Tjikko, which by reproducing through layering, has reached an age of 9,550 years and is claimed to be the world's oldest known living tree.

Description

Morphology

Determining that a tree is a spruce is not difficult; evergreen needles that are more or less quadrangled, and especially the

pulvinus A pulvinus (pl. ''pulvini'') is a joint-like thickening at the base of a plant leaf or leaflet that facilitates growth-independent movement. Pulvini are common, for example, in members of the bean family Fabaceae (Leguminosae) and the prayer plant ...

, give it away. Beyond that, determination can become more difficult. Intensive sampling in the Smithers/Hazelton/Houston area of British Columbia showed Douglas (1975),Douglas, G.W. (1975). Spruce (''Picea'') hybridization in west-central British Columbia. B.C. Min. For., Forest Science, Smithers BC, unpublished report, cited by Coates et al. 1994. (Cited by Coates et al. 1994, orig. not seen) according to Coates et al. (1994),Coates, K.D.; Haeussler, S.; Lindeburgh, S.; Pojar, R.; Stock, A.J. (1994). Ecology and silviculture of interior spruce in British Columbia. Canada/British Columbia Partnership Agreement For. Resour. Devel., Victoria BC, FRDA Rep. 220. 182 p. that cone scale morphology was the feature most useful in differentiating species of spruce; the length, width, length: width ratio, the length of free scale (the distance from the imprint of the seed wing to the tip of the scale), and the percentage free scale (length of free scale as a percentage of the total length of the scale) were most useful in this regard. Daubenmire (1974), after range-wide sampling, had already recognized the importance of the 2 latter characters. Taylor (1959) (Cited in Coates et al. 1994). had noted that the most obvious morphological difference between typical ''Picea glauca'' and typical ''P. engelmannii'' was the cone scale, and Horton (1956,1959)Horton, K.W. (1956). A taxonomic and ecological study of ''Picea glauca'' and ''Picea engelmannii'' in North America. Diploma thesis, Oxford Univ., U.K. 103 p.Horton, K.W. (1959). Characteristics of subalpine spruce in Alberta. Can. Dep. Northern Affairs National Resour., For. Branch, For. Res. Div., Ottawa ON, Tech. Note 76. 20 p. found that the most useful diagnostic features of the 2 spruces are in the cone; differences occur in the flower, shoot and needle, "but those in the cone are most easily assessed" (Horton 1959). Coupé et al. (1982)Coupé, R.; Ray, C.A.; Comeau, A.; Ketcheson, M.V.; Annas, R.M. (1982). A guide to some common plants of the Skeena area, British Columbia. B.C. Min. For., Res. Branch, Victoria BC. recommended that cone scale characters be based on samples taken from the midsection of each of 10 cones from each of 5 trees in the population of interest. Without cones, morphological differentiation among spruce species and their hybrids is more difficult. Species classification for seeds collected from spruce stands in which introgressive hybridization between white and Sitka spruces (''P. sitchensis'') may have occurred is important for determining appropriate cultural regimens in the nursery. If, for instance, white spruce grown at container nurseries in southwestern British Columbia are not given an extended photoperiod, leader growth ceases early in the first growing season, and seedlings do not reach the minimum height specifications.Arnott, J.T. (1974). "Germination and seedling establishment". pp. 55–66 in Cayford, J.H. (Ed.). ''Direct Seeding Symposium'', Timmins ON, Sept. 1973, Can. Dep. Environ., Can. For. Serv., Ottawa ON, Proc., Publ. 1339. But, if an extended photoperiod is provided for Sitka spruce, seedlings become unacceptably tall by the end of the first growing season . Species classification of seedlots collected in areas where hybridization of white and Sitka spruces has been reported has depended on (i) easily measured cone scale characters of seed trees, especially free scale length, (ii) visual judgements of morphological characters, e.g., growth rhythm, shoot and root weight, and needle serration, or (iii) some combination of (i) and (ii) (Yeh and Arnott 1986). Useful to a degree, these classification procedures have important limitations; genetic composition of the seeds produced by a stand is determined by both the seed trees and the pollen parents, and species classification of hybrid seedlots and estimates of their level of introgression on the basis of seed-tree characteristics can be unreliable when hybrid seedlots vary in their introgressiveness in consequence of spatial and temporal variations in contributions from the pollen parent (Yeh and Arnott 1986). Secondly, morphological characters are markedly influenced by ontogenetic and environmental influences, so that to discern spruce hybrid seedlot composition with accuracy, hybrid seedlots must differ substantially in morphology from both parent species. Yeh and Arnott (1986) pointed out the difficulties of estimating accurately the degree of introgression between white and Sitka spruces; introgression may have occurred at low levels, and/or hybrid seed lots may vary in their degree of introgression in consequence of repeated backcrossing with parental species.

Growth

Spruce seedlings are most susceptible immediately following

germination Germination is the process by which an organism grows from a seed or spore. The term is applied to the sprouting of a seedling from a seed of an angiosperm or gymnosperm, the growth of a sporeling from a spore, such as the spores of fungi, fer ...

, and remain highly susceptible through to the following spring. More than half of spruce seedling mortality probably occurs during the first growing season and is also very high during the first winter,Alexander, R.R. (1987). Ecology, silviculture, and management of the Engelmann spruce–subalpine fir type in the central and southern Rocky Mountains. USDA, For. Serv., Washington DC, Agric. Handb. 659. 144 p. when seedlings are subjected to freezing damage, frost heaving and erosion, as well as smothering by litter and snow-pressed vegetation. Seedlings that germinate late in the growing season are particularly vulnerable because they are tiny and have not had time to harden off fully. Mortality rates generally decrease sharply thereafter, but losses often remain high for some years. "Establishment" is a subjective concept based on the idea that once a seedling has successfully reached a certain size, not much is likely to prevent its further development. Criteria vary, of course, but Noble and Ronco (1978),Noble, D.L.; Ronco, F. (1978). Seedfall and establishment of Engelmann spruce and subalpine fir in clearcut openings in Colorado. USDA, For. Serv., Rocky Mountain For. Range Exp. Sta., Res. Pap. RM-200. 12 p. for instance, considered that seedlings 4 to 5 years old, or 8 cm to 10 cm tall, warranted the designation "established", since only unusual factors such as

snow mold Snow mold is a type of fungus and a turf disease that damages or kills grass after snow melts, typically in late winter. Its damage is usually concentrated in circles three to twelve inches in diameter, although yards may have many of these circles ...

, fire,

trampling Trampling is the act of walking on something repeatedly by humans or animals. Trampling on open ground can destroy the above ground parts of many plants and can compact the soil, thereby creating a distinct microenvironment that specific species ...

, or predation would then impair regeneration success. Eis (1967) suggested that in dry habitats on either mineral soil or litter seedbeds a 3-year-old seedling may be considered established; in moist habitats, seedlings may need 4 or 5 years to become established on mineral soil, possibly longer on litter seedbeds. Growth remains very slow for several to many years. Three years after shelterwood felling in subalpine Alberta, dominant

regeneration Regeneration may refer to: Science and technology * Regeneration (biology), the ability to recreate lost or damaged cells, tissues, organs and limbs * Regeneration (ecology), the ability of ecosystems to regenerate biomass, using photosynthesis ...

averaged 5.5 cm in height in scarified blocks, and 7.3 cm in non-scarified blocks (Day 1970),Day, M.W.; Rudolph, V.J. (1970). Development of a white spruce plantation. Michigan State Univ., Agric. Exp. Sta., East Lansing MI, Res. Pap. 111. 4 p. possibly reflecting diminished fertility with the removal of the A horizon.

Taxonomy

Classification

DNA analyses have shown that traditional classifications based on the morphology of needle and cone are artificial. A 2006 study found that '' P. breweriana'' had a

basal Basal or basilar is a term meaning ''base'', ''bottom'', or ''minimum''. Science * Basal (anatomy), an anatomical term of location for features associated with the base of an organism or structure * Basal (medicine), a minimal level that is nec ...

position, followed by '' P. sitchensis'', and the other species were further divided into three

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

s, suggesting that ''Picea'' originated in North America. The oldest record of spruce has been found in the fossil record from the Early Cretaceous around 136 million years ago.

Species

Plants of the World Online Plants of the World Online (POWO) is an online database published by the Royal Botanic Gardens, Kew. It was launched in March 2017 with the ultimate aim being "to enable users to access information on all the world's known seed-bearing plants by ...

accepted 37 species. The grouping is based on Ran et al. (2006). *Basal species: ** '' Picea breweriana'' – Brewer's spruce, Klamath Mountains, North America; local endemic ** '' Picea sitchensis'' –

Sitka russian: Ситка , native_name_lang = tli , settlement_type = Consolidated city-borough , image_skyline = File:Sitka 84 Elev 135.jpg , image_caption = Downtown Sitka in 1984 , image_size ...

spruce, Pacific coast of North America; the largest species, to 95 m tall; important in forestry *Clade I (Northern and western

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

, in boreal forests or high mountains) ** ''

Picea engelmannii ''Picea engelmannii'', with the common names Engelmann spruce, white spruce, mountain spruce, and silver spruce, is a species of spruce native to western North America. It is mostly a high-altitude mountain tree but also appears in watered canyon ...

'' – Engelmann spruce, western North American mountains; important in forestry ** '' Picea glauca'', syn. ''Picea laxa'' – white spruce, northern North America; important in forestry *Clade II (throughout Asia, mostly in mountainous areas, a few isolated populations in higher elevations of Mexico,) ** ''

Picea brachytyla ''Picea brachytyla'' is a species of conifer in the family Pinaceae. It is found in China and northeast India. It is threatened by habitat loss Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a n ...

'' – Sargent's spruce, southwest

China China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...

** '' Picea chihuahuana'' – Chihuahua spruce, northwest Mexico (rare) ** ''

Picea farreri ''Picea farreri'' is a species of conifer in the pine family, Pinaceae. It is known by the common name Farrer's spruce.Burma, southwest

(mountains) ** ''

Picea likiangensis ''Picea likiangensis'', commonly known as Lijiang spruce, Lakiang spruce or Lijiang yunshan, is a species of spruce found in Bhutan Bhutan (; dz, འབྲུག་ཡུལ་, Druk Yul ), officially the Kingdom of Bhutan,), is a lan ...

'' – Likiang spruce, southwest China ** ''

Picea martinezii ''Picea martinezii'', the Martinez spruce, is a medium-sized evergreen tree growing to 25–35 m tall, and with a trunk diameter of up to 1 m. It is native to northeast Mexico, where it occurs at two localities in the Sierra Madre Oriental mount ...

'' – Martinez spruce, northeast Mexico (very rare, endangered) ** ''

Picea maximowiczii ''Picea maximowiczii'', the Japanese bush spruce, is a species of conifer in the pine family. It is endemic to Japan; its range is limited to Akaishi Mountains, Okuchichibu Mountains and the Yatsugatake Mountains on Honshu , historically cal ...

'' – Maximowicz spruce,

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...

(rare, mountains) ** '' Picea morrisonicola'' – Taiwan spruce, Taiwan (high mountains) ** ''

Picea neoveitchii ''Picea neoveitchii'' () is a species of conifer in the family Pinaceae. It is found only in China. It is threatened by habitat loss. ''Picea neoveitchii'' is an endemic spruce species of central China. Several scattered communities and indiv ...

'' – Veitch's spruce, northwest China (rare, endangered) ** '' Picea orientalis'' – Caucasian spruce or Oriental spruce, Caucasus, northeast Turkey ** ''

Picea polita ''Picea polita'', synonym ''Picea torano'', commonly known as the tigertail spruce, is a species of conifer in the genus ''Picea''. It is native to Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in Eas ...

'', syn. ''Picea torano'' – tiger-tail spruce, Japan ** ''

Picea purpurea ''Picea purpurea'', also known as purple cone spruce and purple-coned spruce is a species of spruce found only in China. It is likely to be a hybrid species Hybrid speciation is a form of speciation where hybridization between two different ...

'' – purple cone spruce, western China ** ''

Picea schrenkiana ''Picea schrenkiana'', Schrenk's spruce, or Asian spruce, is a spruce native to the Tian Shan mountains of central Asia in western China (Xinjiang), Kazakhstan, and Kyrgyzstan. It grows at altitudes of 1,200–3,500 metres, usually in pure fore ...

'' – Schrenk's spruce, mountains of central Asia ** '' Picea smithiana'' – morinda spruce, western Himalaya, eastern Afghanistan, northern and northwest India ** '' Picea spinulosa'' – Sikkim spruce, northeast India ( Sikkim), eastern Himalaya ** ''

Picea wilsonii ''Picea wilsonii'' is a species of conifer in the family Pinaceae. It is found only in China China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population e ...

'' – Wilson's spruce, western China *Clade III (Europe, Asia, and North America, mostly in boreal forests or mountainous areas) ** '' Picea abies'' – Norway spruce, Europe; important in forestry, the original

Christmas tree A Christmas tree is a decorated tree, usually an evergreen conifer, such as a spruce, pine or fir, or an artificial tree of similar appearance, associated with the celebration of Christmas. The custom was further developed in early modern ...

** ''

Picea alcoquiana ''Picea alcoquiana'' is a species of conifer in the family Pinaceae The Pinaceae, or pine family, are conifer trees or shrubs, including many of the well-known conifers of commercial importance such as cedars, firs, hemlocks, larches, pine ...

'' – ("''P. bicolor''") Alcock's spruce, central Japan (mountains) ** ''

Picea asperata ''Picea asperata'' (dragon spruce; ) is a spruce native to western China, from eastern Qinghai, southern Gansu and southwestern Shaanxi south to western Sichuan. Description It is a medium-sized evergreen tree growing to 25–40 m tall, and w ...

'' – dragon spruce, western China; several varieties ** '' Picea crassifolia'' – Qinghai spruce, China ** '' Picea glehnii'' – Glehn's spruce, northern Japan, Sakhalin ** '' Picea jezoensis'' – Jezo spruce, northeast Asia, Kamchatka south to Japan ** ''

Picea koraiensis ''Picea koraiensis'', the Korean spruce, is a species of spruce. It is a medium-sized evergreen tree growing to 30 m tall, and with a trunk diameter of up to 0.8 m. The shoots are orange-brown, glabrous or with scattered pubescence. The leaves ...

'' – Korean spruce, Korea, northeast China ** '' Picea koyamae'' – Koyama's spruce, Japan (mountains) ** '' Picea mariana'' – black spruce, northern North America ** ''

Picea meyeri ''Picea meyeri'' (Meyer's spruce; ) is a species of spruce native to Nei Mongol in the northeast to Gansu in the southwest and also inhabiting Shanxi, Hebei and Shaanxi. It is a medium-sized evergreen tree growing to 30 m tall, and with a trunk ...

'' – Meyer's spruce, northern China (from Inner Mongolia to Gansu) ** ''

Picea obovata ''Picea obovata'', the Siberian spruce, is a spruce native to Siberia, from the Ural Mountains east to Magadan Oblast, and from the Arctic tree line south to the Altay Mountains in northwestern Mongolia. Description and uses It is a medium-size ...

'' – Siberian spruce, north Scandinavia, Siberia; often treated as a variant of ''P. abies'' (and hybridises with it), but has distinct cones ** ''

Picea omorika ''Picea omorika'', common name Pančić spruce or Serbian spruce ( sr, Панчићева оморика, Pančićeva omorika, ), is a species of coniferous tree endemic to the Drina River valley in western Serbia, and eastern Bosnia and Herzego ...

'' – Serbian spruce, Serbia and

Bosnia Bosnia and Herzegovina ( sh, / , ), abbreviated BiH () or B&H, sometimes called Bosnia–Herzegovina and often known informally as Bosnia, is a country at the crossroads of south and southeast Europe, located in the Balkans. Bosnia and He ...

; local endemic; important in horticulture ** '' Picea pungens'' – blue spruce or Colorado spruce, Rocky Mountains, North America; important in horticulture ** '' Picea retroflexa'' – green dragon spruce, China ** '' Picea rubens'' – red spruce, northeastern North America; important in forestry, known as Adirondack in musical-instrument making *Others ** ''

Picea aurantiaca ''Picea aurantiaca'' is a species of pinophyta, conifer in the pine family, Pinaceae. It is endemism, endemic to China, where it is only known from western Sichuan. Its common name is orange spruce. This tree grows on steep mountain slopes on th ...

'' Mast. ** ''

Picea austropanlanica 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 (taiga) regions of the Earth. ''Picea'' is the sole genus in the subfa ...

'' Silba ** ''

Picea linzhiensis 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 (taiga) regions of the Earth. ''Picea'' is the sole genus in the subfamil ...

'' (W.C.Cheng & L.K.Fu) Rushforth *Hybrids ** ''Picea'' × ''albertiana'' S.Br. ** ''Picea'' × ''fennica'' (Regel) Kom. ** ''Picea'' × ''lutzii'' Little ** ''Picea'' × notha'' Rehder There is also an extinct species identified from fossil evidence, ''

Picea critchfieldii ''Picea critchfieldii'' (common name: Critchfield's spruce) is an extinct species of spruce tree formerly present on the landscape of North America, where it was once widely distributed throughout the southeastern United States. Plant macrofossil ...

'' which was widespread in the Southeastern United States in the

Late Quaternary The Holocene ( ) is the current geological epoch. It began approximately 11,650 cal years Before Present (), after the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene together ...

Etymology

The

Polish Polish may refer to: * Anything from or related to Poland, a country in Europe * Polish language * Poles, people from Poland or of Polish descent * Polish chicken *Polish brothers (Mark Polish and Michael Polish, born 1970), American twin screenwr ...

phrase ("from Prussia", a region now part of Poland) sounds to English ears like ''spruce''. ''Spruce'', ' (1412), and ' (1378) seem to have been generic terms for commodities brought to England by Hanseatic merchants (especially beer, boards, wooden chests and leather), and the tree thus was believed to be particular to Prussia, which for a time was figurative in England as a land of luxuries. It can be argued that the word is actually derived from the Old French term , meaning literally Prussia.

Ecology

Diseases

''Sirococcus'' blight (Deuteromycotina, Coelomtcetes)

The closely related species ''Sirococcus conigenus'' and ''Sirococcus piceicola'' cause shoot blight and seedling mortality of

conifers Conifers are a group of cone-bearing seed plants, a subset of gymnosperms. Scientifically, they make up the division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single extant class, Pinopsida. All extan ...

in North America, Europe, and North Africa. Twig blight damage to seedlings of white and red spruces in a nursery near Asheville, North Carolina, was reported by Graves (1914). Hosts include white, black,

Engelmann Engelmann may refer to: * Engelmann Oak, also called Pasadena Oak * Engelmann Spruce, a medium-sized evergreen tree * Engelmann syndrome, a rare autosomal dominant genetic disorder * Engelmann (surname) See also * Engelman * Engel (disambigu ...

, Norway, and red spruces, although they are not the plants most commonly damaged. ''Sirococcus'' blight of spruces in nurseries show up randomly in seedlings to which the fungus was transmitted in infested seed. First-year seedlings are often killed, and larger plants may become too deformed for planting. Outbreaks involving < 30% of spruce seedlings in seedbeds have been traced to seed lots in which only 0.1% to 3% of seeds were infested. Seed infestation has in turn been traced to the colonization of spruce cones by ''S. conigenus'' in forests of the western interior. Infection develops readily if conidia are deposited on succulent plant parts that remain wet for at least 24 hours at 10 °C to 25 °C. Longer periods of wetness favour increasingly severe disease. Twig tips killed during growth the previous year show a characteristic crook.

''Rhizosphaera kalkhoffi'' needle cast

''Rhizosphaera'' infects white spruce, blue spruce (''Picea pungens''), and Norway spruces throughout Ontario, causing severe defoliation and sometimes killing small, stressed trees. White spruce is intermediately susceptible. Dead needles show rows of black fruiting bodies. Infection usually begins on lower branches. On white spruce, infected needles are usually retained on the tree into the following summer. The fungicide Chlorthalonil is registered for controlling this needle cast (Davis 1997).Davis, C. (24 September 1997) "Tree talk". ''The Sault Star''. Marie, Ontario. p. B2.

''Valsa kunzei'' branch and stem canker

A branch and stem canker associated with the fungus ''Valsa kunzei'' Fr. var. ''picea'' was reported on white and Norway spruces in Ontario (Jorgensen and Cafley 1961) and Quebec (Ouellette and Bard 1962). In Ontario, only trees of low vigour were affected, but in Quebec vigorous trees were also infected.

Predators

Small

mammal Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...

s ingest

seeds, and also consume seedlings. Cage feeding of deer mice (''Peromyscus maniculatus'') and red-backed vole (''Myodes gapperi'') showed a daily maximum seed consumption of 2000 white spruce seeds and of 1000 seeds of lodgepole pine, with the 2 species of mice consuming equal amounts of seed, but showing a preference for the pine over the spruce (Wagg 1963). The short-tailed meadow vole (''Microtus pennsylvanicus'' Ord) voraciously ate all available white spruce and lodgepole pine seedlings, pulling them out of the ground and holding them between their front feet until the whole seedling had been consumed. Wagg (1963) attributed damage observed to the bark and cambium at ground level of small white spruce seedlings over several seasons to meadow voles. Once shed, seeds contribute to the diet of small mammals, e.g.,

deer mice Deer or true deer are hoofed ruminant mammals forming the family Cervidae. The two main groups of deer are the Cervinae, including the muntjac, the elk (wapiti), the red deer, and the fallow deer; and the Capreolinae, including the reindeer ...

red-backed vole Red-backed voles are small, slender voles of the genus ''Clethrionomys'' found in North America, Europe, and Asia. In recent years the genus name was changed to ''Myodes'', however a 2019 paper found that ''Myodes'' was actually a junior synonym ...

s, mountain voles (''Microtus montanus''), and chipmunks (''Eutamias minimus''). The magnitude of the loss is difficult to determine, and studies with and without seed protection have yielded conflicting results. In western Montana, for example, spruce seedling success was little better on protected than on unprotected seed spots (Schopmeyer and Helmers 1947),Schopmeyer, C.S.; Helmers, A.E. 1947. Seeding as a means of reforestation in the northern Rocky Mountain Region. USDA For. Serv., Washington DC, Circular 772. 30 p. but in British Columbia spruce regeneration depended on protection from rodents (Smith 1955).Smith, J.H.G. 1955

956 acc to E3999 bib Year 956 ( CMLVI) was a leap year starting on Tuesday (link will display the full calendar) of the Julian calendar. Events By place Byzantine Empire * Summer – Emperor Constantine VII appoints Nikephoros Phokas to commander of the ...

Some factors affecting reproduction of Engelmann spruce and alpine fir. British Columbia Dep. Lands For., For. Serv., Victoria BC, Tech. Publ. 43 p.

oates et al. 1994, Nienstaedt and Teich 1972 Oates may refer to: ;People *Oates (surname) *Garfunkel and Oates, comedy act ** Kate Micucci (aka ''Oates'') of "Garfunkel and Oates" *Hall & Oates, musical act ;Places and buildings *Oates, Missouri, a community in the United States *Oates Coast ...

/ref> An important albeit indirect biotic constraint on spruce establishment is the depredation of seed by

squirrel Squirrels are members of the family Sciuridae, a family that includes small or medium-size rodents. The squirrel family includes tree squirrels, ground squirrels (including chipmunks and prairie dogs, among others), and flying squirrels. Squ ...

s. As much as 90% of a cone crop has been harvested by red squirrels (Zasada et al. 1978).Zasada, J.C.; Foote, M.J.; Deneke, F.J.; Parkerson, R.H. 1978. Case history of an excellent white spruce cone and seed crop in interior Alaska: cone and seed production, germination and seedling survival. USDA, For. Serv., Pacific NW For. Range Exp. Sta., Portland OR, Gen. Tech. Rep. PNW-65. 53 p. Deer mice, voles, chipmunks, and shrews can consume large quantities of seed; 1 mouse can eat 2000 seeds per night. Repeated applications of half a million seeds/ha failed to produce the 750 trees/ha sought by Northwest Pulp and Power, Ltd., near Hinton, Alberta (Radvanyi 1972),Radvanyi, A. 1972. Small mammals and regeneration of white spruce in western Alberta. p. 21–23 ''in'' McMinn, R.G. (Ed.). White Spruce: Ecology of a Northern Resource. Can. Dep. Environ., Can. For. Serv., Edmonton AB, Inf. Rep. NOR-X-40. but no doubt left a lot of well-fed small mammals. Foraging by squirrels for winter buds (Rowe 1952)Rowe, J.S. 1952. Squirrel damage to white spruce. Can. Dep. Resour. Devel., For. Branch, For. Res. Div., Ottawa ON, Silv. Leafl. 61. 2 p. has not been reported in relation to young plantations, but Wagg (1963) noted that at Hinton AB,

red squirrel The red squirrel (''Sciurus vulgaris'') is a species of tree squirrel in the genus ''Sciurus'' common throughout Europe and Asia. The red squirrel is an arboreal, primarily herbivorous rodent. In Great Britain, Ireland, and in Italy numbers ...

s were observed cutting the lateral and terminal twigs and feeding on the vegetative and flower buds of white spruce.

Red squirrel The red squirrel (''Sciurus vulgaris'') is a species of tree squirrel in the genus ''Sciurus'' common throughout Europe and Asia. The red squirrel is an arboreal, primarily herbivorous rodent. In Great Britain, Ireland, and in Italy numbers ...

s in Alaska have harvested as much as 90% of a cone crop (Zasada et al. 1978); their ''modus operandi'' is to cut off great numbers of cones with great expedition early in the fall, and then "spend the rest of the fall shelling out the seeds". In Manitoba, Rowe (1952) ascribed widespread severing of branch tips 5 cm to 10 cm long on white spruce ranging "from sapling to veteran size" to squirrels foraging for winter buds, cone failure having excluded the more usual food source. The damage has not been reported in relation to small trees, outplants or otherwise.

Porcupine Porcupines are large rodents with coats of sharp spines, or quills, that protect them against predation. The term covers two families of animals: the Old World porcupines of family Hystricidae, and the New World porcupines of family, Erethizont ...

s (''Erethizon dorsatum'' L.) may damage spruce (Nienstaedt 1957),Nienstaedt, H. 1957. Silvical characteristics of white spruce (''Picea glauca''). USDA, For. Serv., Lake States For. Exp. Sta., St. Paul MN, Pap. 55. 24 p. but prefer red pine. Bark-stripping of white spruce by black bear (''Euarctos americanus perniger'') is locally important in Alaska (Lutz 1951), but the bark of white spruce is not attacked by field mice (''Microtus pennsylvanicus'' Ord), even in years of heavy infestation.

Pests

The eastern spruce budworm ('' Choristoneura fumiferana'') is a major pest of spruce trees in forests throughout Canada and the eastern United States. Two of the main host plants are

black spruce ''Picea mariana'', the black spruce, is a North American species of spruce tree in the pine family. It is widespread across Canada, found in all 10 provinces and all 3 territories. It is the official tree of the province of Newfoundland and Labra ...

and white spruce.Balch, R.E.; Webb, F.E.; Morris, R.F. (1954)
Results of spraying against spruce budworm in New Brunswick
Can. Dep. Agric., For. Biol. Div., Ottawa ON, Bi-mo. Progr. Rep. 10(1). Population levels oscillate, sometimes reaching extreme outbreak levels that can cause extreme defoliation of and damage to spruce trees. To reduce destruction, there are multiple methods of control in place, including pesticides. Horntails, or Wood Wasps, use this tree for egg laying and the larvae will live in the outer inch of the tree under the bark. Spruce beetles ('' Dendroctonus rufipennis'') have destroyed swathes of spruce forest in western North America from Alaska to Wyoming.

Uses

Timber

Spruce is useful as a building wood, commonly referred to by several different names including North American timber, SPF (spruce, pine, fir) and whitewood (the collective name for spruce wood). Spruce wood is used for many purposes, ranging from general construction work and crates to highly specialised uses in wooden aircraft. The Wright brothers' first aircraft, the '' Flyer'', was built of spruce. Because this species has no insect or decay resistance qualities after logging, it is generally recommended for construction purposes as indoor use only (indoor drywall framing, for example). Spruce wood, when left outside cannot be expected to last more than 12–18 months depending on the type of climate it is exposed to.

Pulpwood

Spruce is one of the most important woods for paper uses, as it has long wood fibres which bind together to make strong paper. The fibres are thin walled and collapse to thin bands upon drying. Spruces are commonly used in mechanical pulping as they are easily

bleached Bleached is an American pop band consisting of sisters Jennifer and Jessica Clavin, formerly of Mika Miko. The band plays a style of rock, pop, rock and roll, and indie rock. Bleached was established in Los Angeles in 2011. The group has releas ...

. Together with northern pines, northern spruces are commonly used to make NBSK. Spruces are cultivated over vast areas as pulpwood.

Food and medicine

The fresh shoots of many spruces are a natural source of vitamin C. Captain Cook made alcoholic sugar-based

spruce beer Spruce beer is a beverage flavored with the buds, needles, or essence of spruce trees. ''Spruce beer'' can refer to either alcoholic or non-alcoholic beverages. A number of flavors are associated with spruce-flavored beverages, ranging from flo ...

during his sea voyages in order to prevent scurvy in his crew. The leaves and branches, or the essential oils, can be used to brew spruce beer. In Finland, young spruce buds are sometimes used as a spice, or boiled with sugar to create spruce bud syrup. In survival situations spruce needles can be directly ingested or boiled into a tea. This replaces large amounts of vitamin C. Also, water is stored in a spruce's needles, providing an alternative means of hydration . Spruce can be used as a preventive measure for scurvy in an environment where meat is the only prominent food source .

Tonewood

Spruce is the standard material used in soundboards for many musical instruments, including guitars,

mandolin A mandolin ( it, mandolino ; literally "small mandola") is a stringed musical instrument in the lute family and is generally plucked with a pick. It most commonly has four courses of doubled strings tuned in unison, thus giving a total of 8 ...

s, cellos, violins, and the soundboard at the heart of a piano and the

harp The harp is a stringed musical instrument that has a number of individual strings running at an angle to its soundboard; the strings are plucked with the fingers. Harps can be made and played in various ways, standing or sitting, and in orche ...

. Wood used for this purpose is referred to as tonewood. Spruce, along with cedar, is often used for the soundboard/top of an

acoustic guitar An acoustic guitar is a musical instrument in the string family. When a string is plucked its vibration is transmitted from the bridge, resonating throughout the top of the guitar. It is also transmitted to the side and back of the instrument, ...

. The main types of spruce used for this purpose are Sitka, Engelmann, Adirondack and European spruces.

Other uses

The resin was used in the manufacture of pitch in the past (before the use of petrochemicals); the scientific name ''Picea'' derives from Latin "pitch pine" (referring to Scots pine), from , an adjective from "pitch". Native Americans in

use the thin, pliable roots of some species for weaving baskets and for sewing together pieces of birch bark for canoes. See also

Kiidk'yaas ''Kiidk'yaas'' (meaning "ancient tree" in the Haida language), also known as the Golden Spruce, was a Sitka spruce tree (''Picea sitchensis'' 'Aurea') that grew on the banks of the Yakoun River on the Haida Gwaii archipelago in British Columbia ...

for an unusual golden Sitka Spruce sacred to the

Haida people Haida (, hai, X̱aayda, , , ) are an indigenous group who have traditionally occupied , an archipelago just off the coast of British Columbia, Canada, for at least 12,500 years. The Haida are known for their craftsmanship, trading skills, and ...

. Spruces are popular ornamental trees in horticulture, admired for their evergreen, symmetrical narrow-conic growth habit. For the same reason, some (particularly ''Picea abies'' and ''P. omorika'') are also extensively used as

s, with artificial Christmas trees often being produced in their likenesses. Spruce branches are also used at Aintree racecourse, Liverpool, to build several of the fences on the Grand National course. Spruce wood is also used to make sculptures.

Genome

The nuclear, mitochondrial and chloroplast genomes of British Columbia interior spruce have been sequenced. The large (20 Gbp) nuclear genome and associated gene annotations of interior spruce (genotype PG29) were published in 2013 and 2015.