Arborvitae or White Cedar

Thuja occidentalis L.

     

   

All photographs are copyrighted and are the property of E. Brunner.

Family:  Cupressaceae

Native or Introduced to Illinois:  native 

Leaf:  Leaves are evergreen, scale-like and abruptly pointed, 2 mm long, opposite in alternating pairs (in 4 rows), bright green above and pale green below, sometimes becoming yellow-brown in winter, with a spicy fragrance when crushed.

Cones:  Seed cones are ellipsoid, (6-)9-14 mm long, brown; seeds ca. 8 per cone, 4-7 mm long, with lateral wings about as wide as the body. 

Bark/Twig:  Bark is gray to reddish-brown, 6-9 mm thick, fibrous, separated into flat, connected ridges. 

Size/Form/Shape: Native shrub or tree growing to 15 (-38) meters tall, the crown narrowly conic to broadly pyramidal, with spreading, densely crowded branches; branchlets flattened, in fan-shaped sprays.

Other:  More than 120 named cultivars of northern white cedar have been named and used as ornamental trees and shrubs, where the name “arborvitae” is usually applied.  Selections offer variety in habital form, color, cold hardiness, heat tolerance.  It is often used for hedges and other types of border or shelter plantings.  The species was introduced into Europe for cultivation in the 16th century.  Stands of northern white cedar also are valuable for wildlife habitat, particularly in severe winters for white-tailed deer, which use it for both shelter and browse.  These trees also provide habitats for many species of birds.  

The wood’s light weight and resistance to decay makes it useful for a number of applications.  The principal commercial uses of northern white-cedar are for rustic fencing and posts; other important products include cabin logs, lumber, poles, and shingles.  Smaller amounts are used for paneling, piling, lagging, pails, potato barrels, tubs, ties, boats (especially canoes), tanks, novelties, and woodenware.  The timbers were used to make the ribs in birchbark canoes.  "Cedar leaf oil" is distilled from boughs and used in medicines and perfumes.  Boughs are also used in floral arrangements.  

 The essential oil of northern white cedar is used in cleansers, disinfectants, hair preparations, insecticides, liniment, room sprays, and soft soaps.  The Ojibwa are said to have made soup from the inner bark of the young twigs.  The twigs are used by some to make teas for relief of constipation and headache.    

County Distribution Map for Illinois:  

Sources for the Sullivan Middle School Tree Identification Guide were obtained though the use of the following sites:

• Illinois Plant Information Network (ILPIN) @ http://www.fs.fed.us/ne/delaware/ilpin/ilpin.html#Background
• List of Woody Plants Native or Naturalized in Illinois @ http://www.inhs.uiuc.edu/~kenr/woody.html
• Tree Species @ http://ostermiller.org/tree/species.html
• Index to Eastern/Central Trees @ http://www.arborday.org/trees/ECtreelist.html
• ISU Forestry Extension Identification of Common Trees of Iowa @ http://www.extension.iastate.edu/Pages/tree/
• Key to Leaves of Virginia Trees @ http://www.fw.vt.edu/dendro/forsite/key/intro.htm
• List of Native Trees for Use Along Roadsides in Illinois @ http://www.inhs.uiuc.edu/~kenr/treetable.html
• The PLANTS Database @ http://plants.usda.gov/