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Arbutus spp. |
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Family: Ericaceae |
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Madrone |
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The
genus Arbutus contains about 15 species with 5 in North America and about 10 in
Europe and western Asia.
Arbutus
arizonica : Arizona Madrone,
Arizona Madrono, Madrona
Arbutus
menziesii: Arbuti Tree, Coast Madrone, Laurel, Laurelwood, Madrona, Madrona
Burr, Madrone, Madrone Laurel, Madrone Tree, Madrono, Madrona, Manzanita, Pacific
Madrone, Strawberry-tree
Arbutus
texana : Laurel, Madrona, Madrone, Madrone Tree, Manzanita, Texas Madrone, Texas Madrono
Arbutus
unedo: Strawberry Tree (Europe)
The
following data is for Arbutus menziesii:
Distribution
Southwestern
British Columbia and southward through Washington, Oregon and California in the
coastal mountains.
The
Tree
Pacific
Madrone grows to 80 feet tall, with diameters of 2 to 3 feet. It has orange
branches with shiny leaves, small white flowers in clusters and orange red
fruits.
The
Wood
General
Pacific
Madrone sapwood is a pinkish-cream color, while the heartwood is light pink to
red-brown with patches of deep red. It resembles fruit woods in color and
texture.
Mechanical
Properties (2-inch standard)
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Compression |
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Specific gravity |
MOE 106 lbf/in2 |
MOR lbf/in2 |
Parallel lbf/in2 |
Perpendicular lbf/in2 |
WML* in-lbf/in3 |
Hardness lbf |
Shear lbf/in2 |
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Green |
0.58 |
0.88 |
7600 |
3320 |
780 |
11.2 |
940 |
1420 |
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Dry |
0.69 |
1.23 |
1040 |
6880 |
1620 |
8.8 |
1460 |
1810 |
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Reference (4). *WML = Work to maximum load. |
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Drying
and Shrinkage
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Shrinkage (% of green) |
Green, 0% MC |
Green, 6% MC |
Green, 12% MC* |
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Tangential |
12.4 |
9.9 |
4.1 |
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Radial |
5.6 |
4.5 |
1.9 |
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Volumetric |
18.1 |
14.5 |
6.0 |
Pacific
Madrone is difficult to season, as it warps and checks easily. Schedules for
drying the wood green from the saw have been published (6 & 18). Smith (16)
suggests air drying followed by kiln drying.
Kiln
Drying Schedule:
Working
Properties:
Pacific Madrone works well with all tools and polishes well, but is not easily
glued. The wood is easily worked with tools and compares with hard maple and
eastern white oak in ease of machining (3). Work at FPL (14) indicates that
rotary cutting of veneer is feasible.
Durability:
The wood is not very durable, fence posts had an average service life of 6
years on the untreated condition (7).
Preservation:
No information available at this time.
Uses:
Turnery, bowls, novelties,souvenirs, tool handles, mathematical instruments,
furniture and bowls. Burls are used for pipes and decorative veneers. Charcoal
for gunpowder.
Toxicity:
No information available at this time.
Additional
Reading and References Cited (in parentheses)
1. ASTM. 1955. Book of ASTM
standards. ASTM, Philadelphia, PA,
USA.
2. Boone, R.S., C.J. Kozlik, P.J. Bois &
E.M. Wengert. 1988. Dry kiln schedules
for commercial woods - temperate and
tropical. USDA Forest Service, FPL
General Technical Report FPL-GTR-57.
3. Davis, E.M. 1947. Machining of
Madrone, California laurel, tanbark oak,
and chinquapin. USDA Forest service,
FPL Report No. R1727.
4. Drow, J.T. 1957. Relationship of
locality and rate of growth to density and
strength of Douglas fir. USDA Forest
service, FPL Report No. 2078.
5. Elias, T.S. 1980. The complete trees
of North America, field guide and natural
history. Van Nostrand Reinhold Co.,
New York, 948 pp.
6. Espenas, L.D. 1954. The seasoning of
Oregon hardwoods. OR Forest Products
Lab. Inf. Circular No. 6, 35 pp.
7. Graham, R.D. 1950. Service life of
treated and untreated fence posts. OR
Forest Products Lab. Progress Rep. No.4.
8. Little, Jr., E.L.1979. Checklist of
United States trees (native and
naturalized). USDA Forest Service, Ag.
Handbook No. 541, USGPO,
Washington, DC.
9. Markwardt, L.J. and T.R.C. Wilson.
1935. Strength and related properties of
woods grown in the United States. USDA
Forest Service, FPL Tech. Bull. No.479.
10. Olson, W.Z. 1955. Gluing
characteristics of chinquapin, tanoak,
California laurel, and Madrone. USDA
Forest Service, FPL Rep. No. 2030.
11. Panshin, A.J. and C. de Zeeuw.
1980. Textbook of Wood Technology,
4th Ed., McGraw-Hill Book Co., New
York, 722 pp.
12. Record, S.J. and R.W. Hess. 1943.
Timbers of the new world. Yale
University Press, New Haven, 640 pp.
13. Schniewind, A.P. 1957. The strength
and related properties of Pacific Madrone
I. General description and strength
properties in the green condition. Univ. of
California, School of Forestry, Forest
products Laboratory, California Forestry
and Forest Products, No. 3.
14. Schowalter, W.E. Exploratory tests in
the rotary cutting of veneer from certain
California hardwoods. USDA Forest
Service, FPL Unpubl. Prog Rep. No.
WP-66.
15. Simpson, W.T. 1991. Dry kiln
operator's manual. USDA Forest Service,
FPL Ag. Handbook 188.
16. Smith, H.H. 1954. Seasoning
California hardwoods. USDA Forest
service, California Forest & Range Exp.
Sta., Tech. Pap. No. 3, 18 pp.
17. Summitt, R. and A. Sliker. 1980.
CRC handbook of materials science.
Volume 4, wood. CRC Press, Inc., Boca
Raton, FL. 459 pp.
18. Torgeson, O.W. 1950. Kiln-drying
schedules for 1-inch laurel, Madrone,
tanoak, and chinquapin. USDA Forest
Service, FPL Rep. No. R1684.
19. USDA Forest Service, FPL. 1955.
Wood handbook. Ag. Handbook No. 72. e