Rhamnus spp.

 

this page uses English units of measure

click here to view the file in metric units

 

Family: Rhamnaceae

 

 

 

 

 

 

 

 

click to print or download the file in .pdf format

 

Buckthorn

 

 

 

The genus Rhamnus contains over 100 species native to: North America [5], the rest from the north temperate regions, South America and South Africa. Many non-native species have been naturalized in the US. The name rhamnus is an ancient Greek name.

Rhamnus alaternus-Mediterranean Buckthorn (Europe)

Rhamnus alpinus-Alpine Buckthorn (Europe)

Rhamnus betulifolia-Birchleaf Buckthorn

Rhamnus californica-California Buckthorn, California Coffeeberry, Coast Coffeeberry, Coffeeberry, Pigeonberry, Sierra Coffeeberry

Rhamnus caroliniana-Alder Buckthorn, Birch Bog, Brittlewood, Buckthorn-tree, Carolina Buckthorn, Elbow-brush, Indian Cherry, Pale-cat-wood, Polecat-tree, Polecatwood, Stinkberry, Stink Cherry, Stinkwood, Tree Buckthorn, Yellow Buckthorn, Yellowwood

Rhamnus catharticus-Common Buckthorn, European Buckthorn, European Waythorn, Purgin Buckthorn

Rhamnus crocea-California Redberry, Coffeeberry, Evergreen Buckthorn, Great Redberry Buckthorn, Hollyleaf Buckthorn, Island Buckthorn, Island Redberry Buckthorn, Redberry, Redberry Buckthorn

Rhamnus frangula-(Europe) Alder Buckthorn, Glossy Buckthorn

Rhamnus purshiana*-Bayberry, Bearberry, Bearwood, Bitterbark, Bitterboom, Bittertrad, Buckthorn Cascara, California Coffee, Cascara, Cascara Buckthorn, Cascara Sagrada, Chitam, Chittam, Chittern, Chittim, Coffeeberry, Coffeebush, Coffeetree, Oregon Bearwood, Pigeonberry, Shittimwood, Wahoo, Western Coffee, Wild Cherry, Wild Coffee, Wild Coffeebush, Yellow-wood

Rhamnus zeyheri-(Africa) Pink Ivory, Red Ivorywood

*commercial American species

The following is for Cascara Buckthorn:

Distribution

The Pacific Coast region from British Columbia (incl. Vancouver Island), south to Washington, Oregon and northern California in Coast Ranges and the Sierra Nevada. Also in the Rocky Mountain region of British Columbia, Washington Idaho and Montana.

 

The Tree

Cascara Buckthorn grows in bottom lands, but can be found along fence rows and roadsides. It grows scattered among Douglas fir, maples, western redcedar and hemlock. It grows to a height of 40 feet, with a diameter of 1.5 feet. The bark is thin, thick and smooth, developing brown to gray scales.

The Wood

General

The sapwood of Cascara Buckthorn is yellowish white, while the heartwood is similar but with a red tinge. It is without characteristic odor or taste, is hard and heavy.

 

Mechanical Properties (2-inch standard)

 

 

 

 

Compression

 

 

 

 

Specific

gravity

MOE

x106 lbf/in2

MOR

lbf/in2

Parallel

lbf/in2

Perpendicular

lbf/in2

WMLa

in-lbf/in3

Hardness

lbf

Shear

lbf/in2

Green

0.50

0.63

6,300

3,270

670

13.4

730

1,150

Dry

0.52

0.96

8,700

6,080

1,310

7.8

1,040

1,610

aWML = Work to maximum load.

Reference (59).

 

Drying and Shrinkage

Type of shrinkage

Percentage of shrinkage
(green to final moisture content)

0% MC

6% MC

20% MC

Tangential

4.6

Radial

3.2

Volumetric

7.6

References: (59)

Kiln Drying Schedules: No information available at this time.

Working Properties: No information available at this time.

Durability: No information available at this time.

Preservation: No information available at this time.

Uses: Posts, turnery, furniture parts, novelties, bark and wood extract used for laxative.

Toxicity: Bark and fruits are poisonous, sap causes dermatitis (2 & 5)

Additional Reading and References Cited (in parentheses)

29. Elias, T.S. 1980. The complete trees of North America, field guide and natural history. ?Van Nostrand Reinhold Co., New York, 948 pp.

54. Lampe, Dr. Kenneth F.; McCann, Mary Ann. 1985. AMA Handbook of Poisonous and ?Injurious Plants. American Medical Assoc., Chicago, IL.

55. Little, Jr., E.L.1979. Checklist of United States trees (native and naturalized). USDA ?Forest Service, Ag. Handbook No. 541, USGPO, Washington, DC.

59. Markwardt, L.J. and T.R.C. Wilson. 1935. Strength and related properties of woods ?grown in the United States. USDA Forest Service, Tech. Bull. No. 479. USGPO, ?Washington, DC.

64. Mitchell, J.; Rook, A. 1979. Botanical Dermatology: Plants and Plant Products ?Injurious to the Skin. Greenglass Ltd., 691 W. 28th Ave., Vancouver, British ?Columbia, Canada V5H 2H4.

68. Panshin, A.J. and C. de Zeeuw. 1980. Textbook of Wood Technology, 4th Ed., ?McGraw-Hill Book Co., New York, 722 pp.

74. Record, S.J. and R.W. Hess. 1943. Timbers of the new world. Yale University Press, ?New Haven, 640 pp.

90. Summitt, R. and A. Sliker. 1980. CRC handbook of materials science. Volume 4, ?wood. ?CRC Press, Inc., Boca Raton, FL. 459 pp.?

???