Roble blanco, amapa, mayflower

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Material Information

Title:
Roble blanco, amapa, mayflower Tabebuia pentaphylla (L.) Hemsl. : Family: Bignoniaceae
Series Title:
Report ;
At head of title:
Information leaflet, foreign woods
Physical Description:
7, 3 p. : ; 25 cm.
Language:
English
Creator:
Kryn, Jeannette
Forest Products Laboratory (U.S.)
Publisher:
USDA, Forest Service, Forest Products Laboratory
Place of Publication:
Madison, Wis
Publication Date:

Subjects

Subjects / Keywords:
Bignoniaceae   ( lcsh )
Tabebuia   ( lcsh )
Genre:
federal government publication   ( marcgt )
bibliography   ( marcgt )
non-fiction   ( marcgt )

Notes

Bibliography:
Includes bibliographical references (p. 5-7).
Statement of Responsibility:
by Jeannette M. Kryn.
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 - 029190975
oclc - 244448816
System ID:
AA00020499:00001

Full Text



i -, I


Distribution and Habitat


The genus Tabebuia is widely distributed throughout troric-1 America. It is
divided into three main groups of trees: Roble (a Spanish name for oak),
'qrWhite Cedar," and Lapacho. Each group is represented by species with
distinct wood characteristics. The Roble group, discussed in this report,
includes several species, but the best known is Tabehuia pentaphylla. The
wood bears a superficial resemblance to oak, but it lacks the large rays.
This species is quite common in iexico, Centr-l America, Ecuador, Colombia,
Venezuela, and the West Indies. It grows in various habitats, from wet
lowlands to dry mountainsides (4, 13, 15, 20, 21). .


-41aintained at Madison, Wis., in cooperation with the University of
Wisconsin.
Underlined numbers in parentheses refer to the list of numbered references
at the end of the report.


Agriculture-:adis o-,


EORMAPTION LEAFLET
FOuPE IGI WCOD3


Forest Product4 Laboratoary,- Forest Service
-. ..... S. Department of Agriculture
1954





ROBLE BIA.CO, AMAPA, .MYFLU'.ER
Tabcbuia pentaphylla (L.) Hemsl.
Family: Bignoniaceae





By

JEAifRETTE M. KRYI, Forest Products Technologist
Division of Silvicultural Relations


Rept. No. 1980


-1-







Other Common Names


Roble blanco is also kno-m by the following names (4, 9, 21, 23, 26):


Amapa rosa
Amapola
Apamate
Guayaca n
Hokab
-Tacuelizo
Pacuild
Miacuiles
Macuilixuati
Maculigua
Maculiz
Mano de leon


- Mexico
- 1-!exico
- Venezuela
- Costa Rica
- Mexico
- Honduras
- IJexico
- Salvador
- I'exico
- Salvador
- Mexico
- Guatemala, Honduras


Maqueliz
Maquil
Matilisquate
Orumo
Palo de rosa
Palo yugo
Pink poui
Poirier
Roble de sabana
Roble del rfo
Roble morado
Rosa morado


- Guatemala,
- Mexico
- Guatemala,
- Venezuela
- Mexico
- Mexico
- Trinidad
- Martinique
- Costa Rica
- Colombia
- Colombia
- Mexico


Honduras

Honduras


The Tree


Size

Roble blanco may reach a height of 95 feet and a diameter of 2 feet or more.
Buttresses often extend from 7 to 10 feet up the trunk. Clear boles-20 to
35 and occasionally to 50 feet above the buttresses may occur (3, 4, 15, 17
21_, 22, 23).


Bark

The grayish bark is rough and scaly near the base of the tree, but it is
smooth higher up (11, 19, 21).-


Leaves

The leaves have five leaflets and are in pairs along the stem and clustered
near the ends of the branches. The tree is deciduous (19, 23).


Flowers and Fruit


The flowers are showy, ranging in color from white to deep pink, and the tree
is valued for ornamental planting. The fruits are long, slender pods with
winged seeds (8, iL, 12, 15, 23, 24, 30).


Rept. No. 1980


-2-







The ood


Color

The heartwood is light brown with either a fgr.yish or somewhat -olden hue.
Fine lines of deep brown form a conspicuous pattern, especially on ihe tan-
gential surface. The sapwo.d is yellowish to white iihen freshly cut, ecr.r-
ing light brown after drying and exposure, and not very distinct from the
heartwood (4, 6, 2, 10, 12, 1, 21, 27).


Texture, Grain, Figure

Roble blanco has a medium to rather coarse texture. The grain may be inter-
locked, showing a ribbon-stripe figure on tihe radial or quartersawn surface
of the wood, or it may be straight. The tangential or flatsawn surface
often shows a distinctive figure of fine brown lines, caused by the abundar.t
parenchyma that contains dark, gummy material (4, 9, 10, 21, 25, 31).


Luster

The luster is law to medium (21).


Odor an] Taste

The wood is odorless and tasteless when dry (4, 11).


Weight

Poblo blanco is rated moderately heavy to heavy (4, 9, 21), with an average
specific gravity of 0,52 (0.44 to 0.63) based on weight when ovendry and
volume '-hen green. It averages about 55 pounds per cubic foot when qreen
and 38 pounds ',:hen air-dry (4).


Mechanical Properties:

Values obtained for the mechanical properties of roble blanco in the green
and air-dry condition are given in table 1. Values for white ash (Fraxinus
arr.ericana) and white oak (Quercus alba) arc included for comparison (T2).


Seasoning and Shrinkage

Roble blanco is rated easy to season. Slig .t checking arnd warpin.j -.ay occur
with rapid drying, but these defects can be nininized by slower drying (32).
Kiln schedule 4 of the British Forest Products Resefrcl Laboratory has been


Pept. No. 1980


-3-






recommended (1). The U. S. Forest Products Laboratory schedule that
appears most appropriate for 4/4 stock is T4-D2 (28). Shrinkage data for
roble blanco are given in table 2.

When tested at Yale University, roble blanco showed only fair weathering
characteristics. Exposed, unpainted wood remained free from warp but
developed surface roughness and considerable checking. The heartwood
readily absorbs moisture (32).


Durability

The heartwood of roble blanco is variable in its resistance to decay. It
is given an average rating of "moderately durable" in resistance to a
uhite-rot fungus (Polyporus versicolor) and "very durable" in its resistance
to a brown-rot fungus (Poria monticola) (32). It is rated low in resistance
to insect attack by Dickinson, et al (4), but a report by the Forest Depart-
ment of British Honduras indicates that resistance to fungal and insect
attack is moderately high (11).


Working Characteristics

Roble blanco is very easy to work uith both hand and machine tools and
takes a smooth finish. It holds its place well when manufactured. It has
good nailholding characteristics, but it is advisable to prebore the nail
holes in thick stock. The wood finishes attractively in natural color and
takes stains with good results (4, 5, 21, 27).


Uses

The wood is used locally for ox yokes, house construction, boat building,
piling, carpentry, interior finish and flooring, wagons, and packing boxes
(2, 4, 21, 24, 29, 33). The future demand for the wood in this country
wTll probably be for uses for which it is now best known, namely furniture,
millwork, flooring, and general construction (4).


Structure

Growth rings may be distinct to indistinct. They are delimited by an in-
crease in fiber density and fine lines of terminal parenchyma. Vessels
are distinct without magnification and appear on quarterseawn or flatsawn
surfaces as coarse brown grooves. Parenchyma is terminal, wing-like
about the pores, and confluent. Ripple marks are distinct and regular
(71, 92, 16).


Rept. Hoo 1980


-4-






References


(1) BP.ITISH
1952.


FOREST PRODUCTS RESEARCH LA
KILN-DRY InG SCHEDULES. De
Leaflet No. 42, Revised.
Bucks, England.


BORA TORY
pt. of Sci. and Indus. Re.,
Princes 'isborou:,h, Aylesl-ury,


(2) CUTirI'GS, LEIIS A.
1929. TlH FDRESTS OF VEEZUEL,,. Yale Univ. School Forestry,
Trop. Woods No. 18, pp. 98-39, Ne', Haiven, Conn.


(3) CURP' rJ, HUGH M.
1929. THE LtNDS OF LOBA, COLO'IBLIA.
Trop. Woods No. 19, pp. 15,


Yale Univ. School Forestry,
19,.Neu Haven, Conn.


(4) DICKIISON, FRED. E,, HE.SS, R. W., AiD '.JA'GAARD, F. F.
1949. PROPERTIES AiJD USES CF TROPICAL I"jDS, I. Yale Univ.
School Forestry, Trop. 1oods No. 95, PP. 112-116,
Nev Haven, Conn.

(5) FRITZ, Ei-AiIUL
1926. "AJ-iAPA" FOR INTERIOR TRIM AND FLOORE G. Yale Univ.
School Forestry, Trop. Woods No. 8, pp. 8-9,
New Haven, Conn,

(6) HOLDRIDGE, L. R., TEiSD-.LE, L. V., iLL-iJ:, J. E., LITTuL L., JR.,
HJ.', E. F., .... liAR2ER, J3SE
1947.. THE FCPLSTS OF UESTER? AND CEiITRAL ECJiZ'.:.'R. Pp. 67, 71.
The U. S. Forest Serv., Wlashington, D. C.

(7) JOHi!3TOII, D. R.
1952. THE AiATOMY jX SOI-E SPECIES- OF TADEBUIA. Timber ]:ews,
Vol. 60, pp. 337-338.

(8) KIUGE, H. C., AND rECr'RD, S. J.
1926. TREES OF THE BAYANO RIVER UATERSHET, P.AiIA. Yale Univ.
School Forestry, Trop. Woods No. 5, p. 5, New Haven, Conn.

(9) KRiEPS, DAVID A.
1950. CC[-MERCIAL TREIG:! TOTP3 ON [HE AMLPICA; ;AKET. P. 58.
Trop. Woods Lab, Pennsylvania State College, State
College, Pa.

(10) VfI CCH, WILLIAM, AND INORTOIN, WELL
1938. i*ECHAN1CAL PROFERTUIS C,- CERT' I.- TROPICAL urDS, CHIEFLY
FRCM SOUTH AiL.-P[CA. MITichigan School Forestry and
Conserva. Bull. No. 7, 87 pp., Ann Arbor, "ich.

(11) LA;I-B, A. F. A.
1946. NOTES ON FORTY-'IiO SECONDARY ARiX.:D TEDL-PS CF BRIjTiH
HOIIDURAS. Brit. Honduras Forest Dept. Bull. No, 1,
pp. 60-62, Belize.


Rept. No. 1980


-5-







(12) LAMB, GEORGE N.
1948. FOREIGN WOODS:
Wood Prod.


MAYFLOWER (Tabebuia pentaphylla).
Vol. 53, No. 7, p. 24, Chicago.


(13) LUNDELL,
1937.


C. L.
THE VEGETATION OF PETEN.
244 pp., Washington, D. C


Carnegie Inst. Pub. No. 478,


(14) MARKWARDT, L. J. and WILSON, T. R. C.
1935. STRENGTH AND RELATED PROPERTIES OF WOODS GRCWN IN THE
UNITED STATES. U. S. Dept. Agr., Tech. Bull. 479,
99 pp., Washington, D. C.

(15) MERKER, C. A., BARBOUR, W. R., SCHOLTEN, J. A., and DAYTON, W. A.
1943. THE FORESTS OF COSTA RIGA. Pp. 67, 71. U. S. Forest Serv.,
Washington, D. C.


(16) IMETCALFE, C. R. and CHALK, L.
1950. AiIATOMY OF THE DICOTYLEDONS.


Pp. 1002-1013.


England.


(17) PITTIER, H.
1926. MANUAL DE LAS PLANTS USUALES DE VENEZUELA. 458 pp.
Litographia del Comercia, Caracas, Venezuela.


(18) RECORD,
1927.


(19)




(20)


(21)


SAMUEL J.
TRES OF HONDURAS. Yale Univ. School Forestry, Trop. Woods,
No. 10, pp. 14-15, 46, New Haven, Conn.


1929. TREES AND
EASTERN
No. 17,


SHRUBS COLLECTED BY F. C. EPGLESING IN NORTH-
NICARAGUA. Yale Univ. School Forestry, Trop. Woods,
p.- 22, New Haven, Conn.


___________ and HESS, R.
1940. AMERICAN TIMBERS OF THE FAMILY BIGNONIACEAE. Yale- Univ.
School Forestry, Trop. Woods, No. 63, pp. 24-25, New
Haven, Conn.


1943. TIM4BERS OF THE NEW WORLD. Pp. 83;-89. Yale Univ. Press.,
New Haven, Conn.


______ and
1926. TREES OF THS
Yale Univ.
13-14, 28,


KUYLEN, H.
LOJER RIO ;-iOTAGUA VALLEY, GUATEMALA.
School Forestry, Trop. Woods, No. 7, pp. 11,
New Haven, Conn.


(23) STANDLEY, P. C.
1926. TREES AD4 SHRUBS OF I-EXICO. Contrib. U. S. Natl. Herbarium
Vol. 23, Part 5, pp. 1320-1321, Washington, D. C.


Rept. No. 1980'


(22)


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(24) STJLDLY, P. C.
1928. FLORA 'F THrn FAJLIiL' CiAL ZOV"E. Contrib. U. S. ;itl.
Herbarium Vol. 27, p. 3.. 3, lashington, D. C.

(25) ____
(5 1931. FLO >' :- THE L'CEi-IIA VILLY, HO:M')LPAS. Field Hus. ieat.
Hist., Bot. Ser., Vol. 10, pp. 356-357, Chicago.

(26) _______
1937-38. FLORA Ca COSTA RICA. Field rius. ,'at. Hist., B,)t. 3cr. 18,
Part 3, PP. 1129-1130, Cti.ca* o.

(27) and REC ORD, S. J.
1936. THE FRESTS .ITD FLG.'jkA OF BRITISH H,1DiouiUL". Field i. us.
Nat. Hist., Bot. 3er. Vol. 12, pp. 363-364, Chic-Do.


(28) TORGESOII, 0. W.
1951. SChEDULES FOR THE KILN DPYChG (F WOOD. U. S.
Products Lab. Rept. D1791, 9 pp., 1-1rlison,


Forest
Uis.


(29) W'ADSIORTH, FPAIjK H.
1943. ROBLE, A VALUABLE FO1TEST TRE IN PFUETTO RICC
Forester, Vol. 4, No. 2, pp. 59-76.


(30)


1944. TABEBUIA PALLIDA and TADE3UIA PL.TA. hY:.IA.
Forester, Vol. 5, J!o. 2, p. 99.

(31) WA,-G;JiARD, F. F.
1949. TROPICAL WOOD RESEAFCK. Furn. Ianuf., Vol.
pp. 50-54, 56.

(32) __________ and ?KJSCHLER, A. F.
1952. FROFERTIES AiD USES CF TPOPICAL VWOQDS, III.
School Forestry, Trop. floods, !o. c8, pp.
Haven, Conn.


). Caribbean



Caribbean



64, No. 8,



Yale Univ.
159-163, :ew


(33) '.1!-LLS, L. Venezuela
1939. WADCEI',S LCcrONICAzS [E' "i7- LL. /iIIin. de Agr. Y Cria.,
Bol. Nro. 2, pp. o-cO, Caracas.


Rept. No. 1980


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Table 1.--Mechanical properties of roble blanco (Tabebuia pentaphylla),
white oak (Quercus alba), and white ash (Fraxinus americana)-


Property : Species-
*--------------------------------------------------------
:Roble blanco: White oak : White ash
: (Tabebuia : (Quercus :(Fraxinus
:pentaphylla): alba) : americana)
.. .. ...----...........-- --..........-.--------n--


Moisture content
Green.. .. ..*... .. ..............percent:
Air-dry3...........................percent:

Specific gravity
Based on green volume and ovendry weight..:
Based on volume and weight when ovendry..,:

Static bending
Fiber stress at proportional limit
Green.. . ..... .. .p.s.i.:
Ai -d y ..................O. 00... ..posoi,
MIodulus of rupture
Green.. p.s.i.*:
Air-ryl............. . ...p ,i
Modulus of elasticity
Green.. ....................1,000 p.s.i.:
Air-dry3.............. ....... .1,,00 p.si.:
Work to proportional limit
Green.. *.............in.-lb. per cu. in.:
Air-dry3 .............in.-lb. per cu, ip.:
Work to maximum load
Green.. ........,...in.-lb. per cu.. in.:
Air-dry3............. in.-lb. per cu. in.:

Compression parallel to grain
Fiber stress at proportional limit
Green... . ...*p.s. op i.es :
Air-dry-l. ........... ... ...... ...p.s .i
Maximum crushing strength
Green.. ..........................p.s.i :
..........................p.s.i.
Modulus of elasticity
Green.. ...................1,000 p.s.i.:
Air-dry3....... .... ...... ...1,000 p.s.i.

Hardness4
Green end ............................lb.:
Green side...........................lb
Air-dryl end .................. ..l.... Ib.:
Air-dry3 side............ .......... lb.


68.2
13.5


0.52
0.57


6,,600
9,480

10,770
13.,780

1,450
1,600

1.66
3.18

11.7
12.5



4,040
5,890

4,910
7,340

1,510
1,740


1,030
910
1,310
*960


68
12


0.60:
0.71 :


4,700
S,200


42
12


0.55
0.64


5,100
8,900


8,300 : 9; 600
15,200 : 15,400

1.,250 : 1,460
1,780 : 1,770

1.08 : l.U4
2.27 : 2.60

11.6 : 16.6
14.8 : 17.6



3,090 : 3,190
4,760 : 5,790

3,560 : 3,990
7,440 : 7,410

. ....e. e. o...g e o... o.o.



1,120 : 1,010
1,060 : 960
1,520 : 1,720
1.360 : 1.320


Rept. 1o. 1980


/ *"


*f *


(Sheet 1 of 2)






Table 1.--Mechanical properties of roble blanco (Tatebuia pentaphvlla), uhite
... oak (I:uercus alba), and white ash (Fraxinus arrericina)=. (ccni.inuedl)


Property : Specier'2

:Roble blanco:White oak : White ash
: (Tabebuia : (Quercus :(Fraxinuz
:pentaphylla): alba) : arrcricna)
-----------------------------------------------------C--------.......---
Compression perpendicular to the grain
Stress at proportional limit
Green.. ...... .... .............. .p.8.i.: 790 : 830 : 810
Air-dry3_.........................ps.i. : 940 1,320 : 1,410

Tension perpendicular to grain
Green.. ............................p.s.i.: 790 : 770 : 590
Air-dry2............................p.s.i.: :560 800 : ?40

Shear
Green..............................p.s.i. 1,250 : 1,250 : 1,330
Air-dryl....... ....... .... ..... ..p.s.i. 1,450 : 2,000 : 1,950

Cleavage
Green.. ..............lb. per in. of width: 380 420 : 33)
Air-dryl............lb. per in. of width: *270 450 480

Toughness5 ..............in.-Ib. per specimen: 147.0 L44.9 ...........

IThis table shows results of tests on roble blanco made by the Yale School of
Forestry in cooperation i'ith the Office of Naval Research and the Bureau of
Ships, U. S. Navy Dept. Average strength values for all logs are presented
(32). The results of tests on white oak and white ash, cited in the sTme
Yale report, were taken from U. S. Dept. Agriculture Tech. Bull. 479 (14).
Strength values for roble blanco from Venezuela are not included in this
table, but have been determined on limited material at a different moisture
content by Kynoch and Norton (10).
-Source and number of logs: Roble blanco, British Honduras, 3 logs,
Honduras, 3 logs, and Panama, 3 logs; white oak, United States, 20 logs;
white ash, United States, 23 logs.
-Air-dry values adjusted to 12 percent moisture content except where designated
(*), in which case the actual moisture content at time of testing (see
Moisture Content in table) applies.
4
"The load in pounds required to embed a 0.444-inch steel ball to half its
diaister.
-Toughness values are the average of tests of green and air-dry specimens
5/8 by 5/8 by 10 inches loaded on the tangential face over an 8-inch span.
-Value obtained for plank material received from the New York I.'aval Shipyard.


Rept. No. 1980


(Sheet 2 of 2)







Table 2.-Shrinkage values for roble blanco (Tabebuia pentaphylla)l


Species Shrinkage2-
and ------------------
source :Radial :Tangential: Longitudinal: Volumetric
--------------------------------* ---------------- -- - -
:Percent: Percent : Percent : Percent
Roble blanco
S
Roble 'blanco : : ;


(Tabebuia pentaphylla) :
Panama.* .......... .... :
British Honduras......
Honduras..............:


3.6
3.6
3.7


6.2
6.1
5.9


0.09
.18
.15


-gi
*@--
N a
M


ou 0S
CM^S


10.4
8.7
9.5


----.------------------------ ------
* ft S 9
* 5 4


Average (Panama, :
Brit. Honduras, :
Honduras)...........: 3.6
Venezuela ... 2.6
Venezuela. ...........: 2.6:
*


6.1 :


5.9


.14


* e
*56544* **4 *S ***


* 9.5


9.3


This table shows results of tests on roble blanco made by the
Yale School of Forestry in cooperation with the Office of Naval
Research and the Bureau of Ships, U. S. Navy Department (4, 32).
The results of tests on material from Venezuela were taken from
the report of Kynoch and Norton (10).
2
aShrinkage values represent shrinkage from the green to the ovendry
condition expressed as a percentage of the green dimension.


Rept. N!o. 1980