Comparative decay resistance of heartwood of different native species when used under conditions that favor decay

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Material Information

Title:
Comparative decay resistance of heartwood of different native species when used under conditions that favor decay
Series Title:
Technical note ;
Physical Description:
2 p. : ; 21 cm.
Language:
English
Creator:
Forest Products Laboratory (U.S.)
Publisher:
U.S. Dept. of Agriculture, Forest Service, Forest Products Laboratory
Place of Publication:
Madison, Wis
Publication Date:
Edition:
Rev. May 1961.

Subjects

Subjects / Keywords:
Heartwood -- Deterioration   ( lcsh )
Genre:
federal government publication   ( marcgt )
non-fiction   ( marcgt )

Notes

Additional Physical Form:
Also available online.
General Note:
Caption title.

Record Information

Source Institution:
University of Florida
Rights Management:
All applicable rights reserved by the source institution and holding location.
Resource Identifier:
aleph - 029723755
oclc - 61324829
Classification:
lcc - TA419 .U45 no.229 rev.1961
System ID:
AA00025041:00001

Full Text



TECHNICAL NOT MLR
UNTDSTATES DEPARTMENT OF AGRICULTURE GC13* E 7DERV ICE
FOREST PRODUCTS LABOR 'ORY
*4DSO5. WISCONSIN 1REVISIb*- May16


COMPARATIVE DECAY RESISr ~ A
OF' DIFFERENT NATIVE
UNDER CONDITIONS THAT FAVOR DECAY

Wodkept constantly dry or continuously submerged in water does not dcy. A large proportion of the wood in use is kept so dry at all time s thtit lasts indefinitely. Moisture and temperature are the principal fators which affect the rate of decay; they vary greatly with the local conitins surrounding the wood in service.!1 When exposed to conditosthat favor decay, wood in warm humid areas of the United States dcys more rapidly than in cool or dry areas. High altitudes are as a rleless favorable to decay than low because the average temperaturs are lower and the growing seasons for fungi are shorter.

The natural decay resistance of all common native species of wood is in teheartwood. When untreated, the sapwood of practically all species slow decay resistance and generally short life under decay-producing conitons. The decay resistance or durability of heartwood in service is greatly influenced by differences in the character of the wood, the attacking fungus, and the conditions of exposure. Therefore a widely
difrent length of life may be obtained from pieces of wood that are cut from the same species or even the same tree and used under apparently
smlr conditions.

Gnral comparisons of the relative decay resistance of different species must he estimates. They can not be exact and they may be very mis leading if understood as mathematically accurate and applicable to all cases. They may be very useful, however, if understood as approximate averages only, from which specific cases may vary considerably, and as having application only where the wood is used under conditions that favor decay. The following tabulation of common native species in groups accordingtothe decay resistance of the heartwoodis subjectto the limitations mentioned;

report No. 68, entitled" Factors Which Influence the Decay of Untreated
Wood in Service and the Comparative Decay Resistance of Different
Species discusses this matter inmore detail. Copies of the report
may be obtained, without charge, from the Forest Products Laboratory, Madison 5, Wis.







Resistant or Moderately Slightly or
very resistant resistant nonresistant

Baldcypress Baldcypress Alder
(old growth) (young growth) Ashes
Catalpa Douglas -fir Aspens
Cedars Honeylocust3- Basswood
Cherry, black Larch, western Beech
Chestnut Oak, swamp chestnut Birches
Cypress, Arizona Pine, eastern white BuckeyeJuniper s Pine, longleaf Butternut
Locust, black Pine, slash Cottonwood
Me squite Tamarack Elms
Mulberry, red4. Hackbe rry
Oak, bur Hemlocks
Oak, c he stnut Hickories
Oak, Gambel Magnolia
Oak, Oregon white Maples
Oak, post Oak (red and black
Oak, white species),3
Osage-orange- Pines (most other
Redwood species
Sassafras Poplar
Walnut, black Spruces
Yew, Pacific Sweetguma
Sycamore
Willows
Yellow-poplar

2_These woods have exceptionally high decay resistance. IThese species, or certain species within the groups shown, are in
dicated to have higher decay resistance than most of the other woods
in their respective categories.
UNIVERSITY OF FLORIDA

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