blue spruce


  • [6] ‘Mission Blue’ blue spruce new growth in spring Pests and diseases[edit] The blue spruce is attacked by two species of Adelges, an aphid-like insect that causes galls
    to form.

  • [19] Five years before transplanting, the total root surface area of 2-meter-high trees was doubled by pruning the roots of blue spruce.

  • [20] Cultivars Common cultivars (those marked AGM have gained the Royal Horticultural Society’s Award of Garden Merit):[21] • ‘Glauca Globosa’ AGM[22] – shrub from 3–5 feet
    (0.91–1.52 m) in height[23] • ‘Fat Albert’ – compact perfect cone to 10 feet (3.0 m) of a silver blue color[24] • ‘Glauca Pendula’ – drooping branches, spreads to about 8 feet (2.4 m) wide by 4 feet (1.2 m) tall[25] • ‘Sester’s Dwarf’ – denser
    foliage than the species, slowly grows to about 6–8 feet (1.8–2.4 m) tall[26] • ‘Hoopsii’ AGM[27] • ‘Koster'[28] • ‘Baby Blue Eyes'[29][30] • ‘Baby Blue'[31] Uses The Navajo and Keres Native Americans use this tree as a traditional medicinal
    plant and a ceremonial item, and twigs are given as gifts to bring good fortune.

  • [33] Blue spruce always grow naturally in the soils which are in the order Mollisols, and the soil will also be in the orders histosols and inceptisols in a lesser extent.

  • [38][40] Blue spruce is generally considered to grow best with abundant moisture.

  • [13] Rooting habits Blue spruce seedlings have shallow roots that penetrate only 6.4 cm (2.5 inches) of soil during the first year.

  • Canker caused by Cytospora attacks one of the lower branches first and progressively makes its way higher up the tree.

  • It often first attacks trees which have blown over by the wind and when the larvae mature two years afterwards, a major outbreak occurs and vast numbers of beetles attack
    nearby standing trees.

  • An elongated white scale insect, the pine needle scale feeds on the needles causing fluffy white patches on the twigs and aphids also suck sap from the needles and may cause
    them to fall and possibly dieback.

  • Mites can also infest the blue spruce, especially in a dry summer, causing yellowing of the oldest needles.

  • The tree can grow larger if the tip is cut when it is at least 3 years old.

  • [16] Although freezing can’t damage much in blue spruce, frost will cause seedling loss.

  • [15] The blue spruce is susceptible to several needle casting diseases which cause the needles to turn yellow, mottled or brown before they fall off.

  • [4] It has been widely introduced elsewhere and is used as an ornamental tree in many places far beyond its native range.

  • Various rust diseases also affect the tree causing yellowing of the needles as well as needle fall.


Works Cited

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(Pinaceae – Pine Family)”.
3. ^ “Colorado Blue Spruce”. Retrieved 2018-11-20.
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University Press, New York, 475 pp
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J. Wagner Jr. (September 15, 1981). Michigan Trees: A Guide to the Trees of Michigan and the Great Lakes Region. Biological Science Series. University of Michigan Press. ISBN 978-0-472-08018-2.
8. ^ Vedel, H.; Lange, J. (1962). Trees and Bushes.
Methuen & Co. pp. 119–120. ISBN 978-0416617801.
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Trees & State Flowers”. United States National Arboretum. June 11, 2009. Archived from the original on 2010-12-06. Retrieved 2010-05-26.
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“Picea pungens: Colorado Spruce”. EDIS. IFAS Extension Service: University of Florida. Retrieved 2013-10-06.
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Ciesla, Bill (2013-04-19). “Spruce Beetle Threatens High Country Spruce Forests”. Colorado State University Extension. Retrieved 2013-10-05.
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the United States”. U.S. Department of Agriculture, Agriculture Handbook.
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Station, Fort Collins.
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Watson, Gary W; Sydnor. “The effect of root pruning on the root system of nursery trees”. Journal of Arboriculture.
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Selector – Picea pungens (Glauca Group) ‘Globosa'”. Retrieved 6 February 2021.
23. ^ Missouri Botanical Garden: Picea pungens ‘Glauca Globosa’
24. ^ Missouri Botanical Garden: Picea pungens ‘Fat Albert’
25. ^ Fine Gardening Plant Guide:
Picea pungens ‘Glauca Pendula’
26. ^ Washington State University Extension: Sester’s Dwarf Blue Spruce
27. ^ “RHS Plant Selector – Picea pungens (Glauca Group) ‘Hoopsii'”. Retrieved 6 February 2021.
28. ^ “RHS Plant Selector – Picea pungens
‘Koster'”. Retrieved 27 May 2013.
29. ^ “Missouri Botanical Garden – Picea pungens ‘Baby Blueeyes'”.
30. ^ “Washington State University – Picea pungens ‘Baby Blueeyes'”.
31. ^ “West Montrose Farms Ltd – Picea pungens ‘Baby Blue'”.
32. ^
U. Michigan-Dearborn: Ethnobotany Accessed 2020-12-20
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34. ^ Mauk, Ronald L.; Henderson. “Forest habitat types of northern Utah. USDA Forest Service General Technical
Report INT-170”. Intermountain Forest and Range Experiment Station.
35. ^ Moir, William H.; Ludwig, John A. “A classification of spruce-fir mixed conifer habitat types of Arizona and New Mexico”. USDA Forest Service, Research Paper RM-207.
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Dixon, Helen (1935). “Ecological Studies on the High Plateaus of Utah”. Botanical Gazette. 97 (2): 272–320. doi:10.1086/334554. JSTOR 2471603. S2CID 84538967.
37. ^ Jump up to:a b Fechner, Gilbert H. “Blue Spruce”. Retrieved 2018-11-23.
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Jump up to:a b Bates, Carlos C. “Forest types in the central Rocky Mountains as affected by climate and soils”. U.S. Department of Agriculture, Bulletin 1233: 152p.
39. ^ Pearson, G. A. “Forest types in the Southwest as determined by climate and
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“Forest tree planting in arid zones”. Soil Science. 124 (1): 504p. Bibcode:1977SoilS.124…66C. doi:10.1097/00010694-197707000-00012.
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