Odoko

MISSING IMAGE

Material Information

Title:
Odoko
Physical Description:
Mixed Material
Creator:
Kryn, Jeanette M
Forest Products Laboratory (U.S.)
Publisher:
United States Dept. of Agriculture, Forest Service, Forest Products Laboratory ( Madison, Wis )
Publication Date:

Record Information

Rights Management:
All applicable rights reserved by the source institution and holding location.
Resource Identifier:
aleph - 29357765
oclc - 756756235
System ID:
AA00020649:00001

Full Text
I'


INtOI.M rION IO '/-I T
FoPT I'GN W_. .rI;

1
Forest Products Laboratory,- forest .'rvice
U. S. Dejurtment ouT :,-jriculturc
195,4






CD,-I:O
Scottellia coriacea A. Chev.
Family: 'lacourt!aceae


JEANNETTE M. KRTI, Forest Products Techjologist
Division of Silvicultural Felations





Distribution and Habitat


There are more than 70 genera in the family Flacourtiaceae, widely distributed
throughout the tropics. The genus Scottellia occurs in W.est Africa from
Liberia to southern Nigeria and is reported to be abundant (2, 4, 6)._


The Tree


Size

Odoko varies from a medium height of 50 to -0 feet to a maximum of !',0 feet,
usually with a straight bole. Diameters range from about a foot to 2 or 5 feet
(2 4, 6).
1
-Maintained e.t Madison, Wis., in cooperation with the University of '.isconsin.
2
Underlined numbers in parentheses refer to the list of numbered references
at the end of the article.


Agr i culture -:ad son


Report No. 1973


-1-







Bark

The outer bark is reddish (4).


Leaves, Flowers, Fruits

The leaves are smooth and leathery, oval, and 3 to 5 inches long. The
flowers are small, creamy yellow, and slightly fragrant. The fruits grow
in clusters and are elongated capsules with a few orange-red seeds (4).


The Wood


Color

The wood is pale yellow or straw-colored, without distinction between sap-
wood and heartwood. It is subject to blue stain (2, 4, 6).


Texture, Grain, Figure

Odoko is generally straight-grained, but it may occasionally have inter-
locked grain. The texture is fine. A distinct "silver-grain" figure
appears on the quarter-cut surface because of the relatively conspicuous"
rays (2, 4, 6).


Weight

In tests conducted at the British Forest Products Research Laboratory, air-
dried wood at 12 percent moisture content weighed 41 pounds per cubic foot;
green wood at 50 percent moisture content weighed 53 pounds per cubic foot (1).


Mechanical Properties

Values obtained for the mechanical properties of odoko in the green and air-
dry condition are presented in table 1 (1).


Seasoning and Shrinkage

Odoko is reported to develop checks and splits during air-drying. Blue
stain may also occur. Warping is usually not excessive.

In kiln drying, the wood has a tendency to split and existing shakes tend
to enlarge. There is little distortion in drying (2, 6). Kiln schedule 5 of
the British Forest Products Research Laboratory has been recommended for this


Report No. 1973


-2-








timber (). The U. S. Forest Products Laboratory sc.'-dule tlat a:;'8
most appropriate for 4/4 stock is T6-D2 (10). Limited tests at 4-1 ;-:ti:K.
Forest Products Pesearch Laboratory resulted in the follwIn, 8hrri.,e
data on kiln drying from the green condition to a moisture content f bout
10 percent (2):

Tangential....................... 1/2to 5/8 inch per foot, or
4.0 to 5.0 percent.

Radial ................... ......1/4 to 5/16 inch per foot, or
2.3 to 2.4 percent.


Durability

Odoko is not resistant to decay, but it can easily be treated with pre-
servatives (2, 6).


Working Characteristics

The wood is rated moderately easy to work. It finishes smoothly in rlaning
and molding and takes a good polish, but some care is needed to prevent
chipping in certain operations because of a slight brittleness. Quarter-
sawn surfaces sometimes tend to flake. The timber is liable to split in
nailing, but it has good gluing and screwholding characteristics (2, 6).

H. A. Cox (5) reported that logs from Nigeria showed a tendency to develcE
radial splits sometimes reaching to the circumference of the log during the
process of cross-cutting to lengths suitable for the veneer cutting machine.
This made peeling difficult, for the veneer tended to break across as it
was removed from the peeler.


Uses

Odoko is a good general utility timber somewhat similar to beech. It should
prove useful for table tops as in bakeries and laundries, brush backs, shoe
heels, and domestic woodenware (2, 6).


Structure

Growth rings are not distinct. Pores are small and not visible without a
lens. Wood parenchyma is absent or very sparse. RF.ays are conspicuous
on the cross section but not on the tangential section; they are notably
high and prominent on the radial surface where they stand out as lighter
than the background (8, 9, 11).


Report No. 1975


-5-







References


1. Armstrong, F. H.
1955. The Strength Properties of Timber.
Bull. No. 28, p. 39, Dept. of Sci. and Indus.
Research, Forest Products Research Laboratory,
Princes Risborough, Aylesbury, Bucks, England.

2. British Forest Products Research Laboratory
1945. A Handbook of Empire Timbers.
Pp. 76-77. Dept. of Sci. and Indus. Research,
Forest Products Research Laboratory, Princes
Risborough, Aylesbury, Bucks, England.

3. __________________________________
1952. Kiln-Drying Schedules.
Leaflet No. 42, Revised March, 1952. Dept. of Sci.
and Indus. Research, Forest Products Research
Laboratory, Princes Risborough, Aylesbury, Bucks,
England.


4. Cooper,
1931.



5. Cox. H.
1940.





" 6. Jay. B.
1950.


G. P., and Record, S. J.
The Evergreen Forests of Liberia.
Bull. No. 31, p. 28, Yale Univ. School of
Forestry, New Haven, Conn.

A.
Notes on Empire Timbers.
Empire Forestry Journal Vol. 19, No. 2, pp. 292-
294. London.
(Rev. in Trop. Woods No. 66, p. 51, June 1941
Yale Univ. School of Forestry, New Haven, Conn.)

A.
Timbers of West Africa. 3rd. ed.
Pp. 65-66. Timber Development Association, Ltd.,
London.


7. Markwardt, L. J. and Wilson, T. R. C.
1935. Strength and Related Properties of Wood Grown
in the United States.
U. S. Dept. Agr. Tech. Bull. No. 479. 99 pp.
Washington, D. C.

8. Metcalfe, C. R. and Chalk, L.
1950. Anatomy of the Dicotyledons.
Vol. 1, pp. 116-127. Clarendon Press, Oxford,
England.


Report No. 1973


-4-








9. Stone, H. and Cox. H. A.
1 2?. Timbers of Nigeria.
Pp. 11-12. School of Forestry, Univ.,
Cambridge, England.

10. Torgeson, 0. W.
1951. Schedules for the Kiln Drying of Wood.
U. S. Forest Products Lab. Rept. No. D1791, 9 pp.

11. Tupper, Walter W.
1934. Preliminary Report on the Wood Structure of
the Flacourtiaceae.
Trop. Woods No. 38, pp. 11-14, Yale Univ. School
of Forestry, New Haven, Conn.


Report No. 1973


-5-







Table 1.--Mechanical properties of odoko ()Scottelli rA ) and the
comparable hardwoods, European beech (Fagus sylvatica) and
American beech (Fagus grandifolia)l:


Property


Species and origin


Odoko :American:European :European
:(Scottellia : Beech : Beech : Beech
coriacea) : (Fagus : (Fagus :(Fagus
: Nigeria : grandi- sylvaticaa) sylvaticaa)
: folia) : United :-hurope
: United : Kingdom
States:
-- .-.----------------------------------- :---
- - - - ~ ~ ~ ~ - ~ - a m^ - ^ ^ ^ .w w ~ w ^ ^ ^ ^ ^ -. .. m ..


Moisture content
Green............. .... ... percent
Air-dry....... .............percent

Weight per cubic foot
At 50 percent moisture content.lb.:
At 12 percent moisture content.lb.:

Static bending
Modulus of rupture
Green .................... p.s.i.:
Air-dry .................. p.s.i.:
Modulus of elasticity
Green.............. 1,000 p.s.i.:
Air-dry.............1,000 p.s.i.:
Work to maximum load
Green.......in.-lb. per cu. in.:
Air-dry.....in.-lb. per cu. in.:
Total work
Green....... in.-lb. per cu. in.:
Air-dry.....in.-lb. per cu. in.:

Impact bending
Height of drop causing complete :
failure (50-pound hammer)


54 :
12 :


53
41



11,500
16,000

1,750
1,990

12.7
12.0

22.2
16.9


: 45
* li




8,600
:14,900

: 1,380
: 1,720

11.9:
51.1:

30.8:
S 30.9:




43
41


52
43



8,900
16,200

1,520
1,950

13.2
17.4

26.3
27.4




36
45


: 12


* 40




13,500


1,680


: 14.1








: 43


Compression parallel to grain
Maximum crushing strength
Green....................p.s.i.:
Air-dry...... . ........* p.s.i.:


Report No. 19753


5,390
8,880


3,550
7,300


3,860
7,870


Green....................... in.: ...........
Air-dry ..................... in.: ...........


(Sheet 1 of 2)








Table 1.--Mechanical properties of odoko (Scottellit cjr'ic'l,) .r'] the
comparable hardwoods, European beech (LFus oylvti-t ; ind
American beech (Fagus grandifolia)! (Continued)


Property


2
Hardness
Green end.................... lb.:
Green side....... ........ ....lb.:
Air-dry end..................ib.:
Air-dry side.................Ilb.:

Shear parallel to grain; maximum
shearing strength
Green. .... ....... ... .. .... .p.s.i. :
Air-dry.. .... ..,..... ........p.s.i. :

Cleavage; load to cause splitting :
Green.........Ib. per in. of width:
Air-dry.......lb. per in. of width:


Species and orif'n

Odoko :American: iuropean : ur-rean
:(Scottellla: Beech : Beech : Beech
coriacea) (Fagus (Fagus (Farus
Nigeria : grandi-:sylvatica) :silvitica)
: folia) : United : urore
: "United : Kinrdom
: States :


1,150
990
1,620
1,090


1,280
.1,910


970
850
1,590
1,300


1,290
2,010


410
490


1,080
960
1,820
1,440


: 1,690
: 1,180


1.210
2,030


490
525


: 4350


'This table shows results of tests on


odoko and European


British Forest Products Research Laboratory (1). The
American beech were taken from Tech. Bull. No. 479 of
Agr. (i).
2The load in pounds required to embed a 0.444-inch steel
diameter.
hLimited number of tests.


beech made by the
results of tests on
the U. S. Dept. of

ball to half its


Report No. 1973


(Sheet 2 of 2)




UN.VERiTY OF FLORIDA
III 1111llll 11111 0l 4 4 ll 1111i 111111111111 lll ll1
3 1262 08866 4841


N