The Black Hills spruce adopted by the South Dakota Legislature is considered a regional variety of white spruce (Picea glauca) found only in the Black Hills of South Dakota. This Black Hills distinction is not universally accepted however.
According to the S.D. Department of Agriculture, Division of Forestry:
Black Hills spruce is a variety, or subspecies, of the widely distributed white spruce. White spruce has bluish-green foliage while the Black Hills spruce has a typically denser and a bright bluish-green foliage. Black Hills spruce is also a slower growing species than white spruce. While Black Hills spruce has been given the variety distinction, it is now considered to be a geographical variety, rather than a botanical variety.
The following information was excerpted from the South Dakota Codified Laws , title 1, chapter 1-6, section 1-6-11.
TITLE 1 STATE AFFAIRS AND GOVERNMENT
CHAPTER 1-6 STATE EMBLEMS
1-6-11. State tree.
1-6-11. State tree. The Black Hills Spruce, Picea glauca densata, being a tree native to the State of South Dakota and by its name definitely designating this state as its own and being a tree of noble attributes, is hereby named to be the state tree of South Dakota.
Source: SL 1947, ch 266; SDC Supp 1960, § 55.0112.
The State of South Dakota. South Dakota Codified Laws. Pierre: State of South Dakota. Web. 12 Jul 2011. <http://legis.state.sd.us/statutes/TitleList.aspx>.
Herman, D.E., et al. North Dakota Tree Handbook. Bismarck: USDA NRCS ND State Soil Conservation Committee; NDSU Extension and Western Area Power Administration, 1996. Print.
Shearer, Benjamin F. and Barbara S. State Names, Seals, Flags and Symbols: A Historical Guide Third Edition, Revised and Expanded. Westport, Conn: Greenwood Press, 3 Sub edition, 2001.
State Tree: Black Hills Spruce: South Dakota Department of Transportation: Kid's page.
Black Hills sprucs Picea glauca var. densata: Black Hills Spruce fact sheet from the S.D. Department of Agriculture, Division of Forestry, Pierre, SD.
Black Hills Spruce: North Dakota Tree Handbook.
North Dakota Tree Handbook: North Dakota State University - North Dakota Forest Service.
Black Hills Spruce Picea glauca 'Densata': Monrovia Horticultural Craftsmen.
CalPhotos Photo Database: Photographs of Picea glauca from CalPhotos, a project of the Biodiversity Sciences Technology group (BSCIT), part of the Berkeley Natural History Museums at UC, Berkley.
White spruce (Picea glauca (Moench) Voss: Tree Identification Fact Sheet from the Virginia Tech.
White spruce (Picea glauca (Moench) Voss: Landowner Fact Sheet from the Virginia Tech.
Plant Profile for Picea glauca (Moench) Voss (white spruce): USDA, NRCS. 2011. The PLANTS Database (http://plants.usda.gov, 24 July 2011). National Plant Data Team, Greensboro, NC 27401-4901 USA.
Picea glauca (Moench) Voss (White Spruce): United States Department of Agriculture: Forest Service: Agriculture Handbook 654: Silvics of North America.
Picea glauca var. densata Bailey: Integrated Taxonomic Information System (ITIS) Here you will find authoritative taxonomic information on spiders, animals, fungi, and microbes of North America and the world.
State trees: Complete list of official state trees from NETSTATE.COM.
More symbols & emblems: Complete list of official South Dakota state symbols from NETSTATE.COM.
The Tree Book for Kids and Their Grown Ups, by Gina Ingoglia. 96 pages. Publisher: Brooklyn Botanic Garden (October 7, 2008) Reading level: Ages 9-12. How do trees grow? Why do leaves change color? What kind of tree is that? After you and your children read this book, you’ll know! Featuring 33 different trees that grow in North America, The Tree Book’s beautiful illustrations show each tree as it appears in a particular season, as well as life-size depictions of its buds, leaf, flower, fruit, and seed. Histories of each tree bring to life its character and significance to us.
A Field Guide to Western Trees, by George A. Petrides. 448 pages. Publisher: Houghton Mifflin Harcourt; Second Edition edition (July 25, 1998) A Field Guide to Western Trees features detailed descriptions of 387 species, arranged in six major groups by visual similarity. The 47 color plates and 5 text drawings show distinctive details needed for identification. Color photographs and 295 color range maps accompany the species descriptions.
Trees of the Northern United States and Canada , by John Laird Farrar. 502 pages. Publisher: Wiley-Blackwell; 1 edition (January 16, 1991) Trees of the Northern United States and Canada is the most complete book on the trees of northern North America ever published. It features:
Trees for the Northern United States and Canada is a must for the forest professional, landscape architect, amateur naturalist, student, or teacher and for anyone who is fascinated by trees and forests.
The Sibley Guide to Trees, by David Allen Sibley. 426 pages. Publisher: Knopf (September 15, 2009) Monumental in scope but small enough to take into the field, The Sibley Guide to Trees is an astonishingly elegant guide to a complex subject. It condenses a huge amount of information about tree identification—more than has ever been collected in a single book—into a logical, accessible, easy-to-use format.
With more than 4,100 meticulous, exquisitely detailed paintings, the Guide highlights the often subtle similarities and distinctions between more than 600 tree species—native trees as well as many introduced species. No other guide has ever made field identification so clear.