1° • Pr - _;_ -v., " Fore; I i /ice ; .'. S. De"oartment of \griculture 1951 i . ir . • iaa ii Hura crepitans L. Hura polyandra 3ai.ll. ily: :r)horbiaceae By pLOISE GERRY, Forest Products Technologist Division of Silvi cultural Relations Common Ilames Acuapa Colombia Acuapar Colombia Irbol del diablo. . . .Mexico Irenillo Colombia Arenillero Colombia 'icu E 'rar.il 3oio du diable French V: est Indies Castaneto Colombia Catahua Peru Ce: ba amarilla Colombia Ceiba blanca Colombia, Venezuela Ceiba habillo Venezuela Ceiba de leer-- Colombia, Venezuela Ceiba de le cha s a . . . . Colombi a , Venezuela Ceibo Colombia, Venezuela Haba Cuba, Mexico Haba de indio Mexico Haba de San Ignacio. Mexico Haba de Guatemala. . .Mexico Habillo or (a) Cuba, Mexico, Colomiba, Peru, Venezuela Havillo Mexico Hura wood trade Lo or (a) Leo, Central America, Venezuela Javarillo Javillo or (a) Mi linillo 1 -pesos .: -y' . iir n< rbell. . . Nune lie I 4 : a de San ] Fet du diable Possentrie (Poison tree;. . . . Postentrie Possur.r.vood I iatlatzin latli Rakuda Sablier Salvadera. Sandbox tree. Seda blanca. . Solimanche. . . :;reta Tronador Uassacu Puerto Rico Cuba, Puerto Rico, Dominican Republic, Venezuela Puerto Rico Colombia British Vest Indies Panai Bolivia VOX: Mexico French Vest Indies Suri - Surinam II . S. trade Mexi co Mexico . trade Haiti, French Indies n , Colombo . Peru 3rii ; indies .pi can P.epubi Mexico Gua? Panama 11 ntainec at Madison, Wis., in cooperatio t)-.e University nsin. Rept. No. P1902 -1- culture-Madisor Distribution and Habitat Two closely related species of Hura occur as large trees from the "'est Indies and southern Mexico to northern Brazil. The Mexican species ( H. polyandra Braill.) differs little from the more widely distributed Hura wood ( H.' crepitans L.) (1Z)«~ The best growth is reported to be on the low narrow reefs of the coastal plain near Paramaribo, Surinam, where nearly pure stands, yielding 6,000 to 100,000 board feet per acre and averaging 2^,000 board feet per acre ever an area of 20,000 acres, are found. In Colombia, it is common along the tributaries of the Magdalene River, especially in the region about El Banco. In Venezuela, it is found along the banks of streams and in the moist valleys of the coast range and is cut along the shores of Lake Maracaibo. The Tree The trees growing in the open may have relatively short, thick trunks, but in the forest they may attain heights of 90 to 130 feet or even as high as 200 feet. The forest trees have straight, fairly regular trunks often free of branches for from 1+0 to 100 feet and commonly 3 to 5 feet or sometimes 6 to 9 feet in diameter above the rather small buttresses. These trees often have sharp spines on branches and trunk. They are reported to be associated with workmen' s poisoning. The trees are extensively cultivated for shade and decorative purposes in the tropics of both hemispheres. Bark The bark is thick and rather smooth except near the base of the tree where it is covered with the short conical spines mentioned (11). It contains a caustic latex that spatters when a tree is cut* This latex is irritating to the eyes and skin and is poisonous if taken internally. It is sometimes used for stupifying fish (18) and also has been used as a remedy for elephantiasis and leprosy. Leaves The leaves resemble those of cottonwood. Flowers and Fruit The flowers are dark red and borne in the form of a cone. The structure of the stamens is used in distinquishing species. The fruits resemble little pumpkins (sandbox) and explode on drying, scattering wafer-like seeds which contain 5>0 percent of oil and are used to poison animals. 2 Underlined numbers in parentheses refer to the list of numbered references at the end of the article. Rept. Ho. R1902 -2- The Y. T ood General Appearance The wood superficially resembles Simaruba , but lacks the bitter taste. CoIt The wood varies in color from a lustrous creamy white to light buff when fresh, occasionally with indistinct purplish or g . h streaks. V.'hen dry, it may ear yellov/ish brown or pale olive gray. ■ : ■ - The wood is moderately light, comparable to yellow-poplarj specific gravity 0,38 (0.31 - 0.51) based on oven-dry weight and green volume or a weight of about iiO pounds per cubic foot green and 28 pounds air-dry (11). y. ; -,r^, Grain, and Figure The wood is rated as fine to medium textured. It cuts with a more or less lly surface. Some has an attractive "roe" grain or ribbon stripe on the Lai surface, although +!e figure is usually not pronounced except in crotches. The grain is generally interlocked but maybe straight (11). Luster r is rated as high (11). _: Taste Odor and taste are lacking (11). "or king Qualities Alt: somewhat difficult to saw when green because of the extreme fuzziness of the cut surface, the wood can be readily machined when dry. Lack of clean cutting and chipped and torn grain are frequently encountered with material Lch has extremely interlocked grain. The wood takes stains well and glues readily (11). . •i.ar.ical Properties (11) The followir. ; 1 in table 1 were obtained in recent tests conducted at Yale School of Forestry in cooperation with the Office of Naval Research and the hireau of Ships, U. S. Navy Department, under Contract No ori-Ui Task Order XV (Project Designation 'Jo. NR-033-020) and published in Trop' oods Mo. 97, v. 1, 1950* page 7U« Comparative data for yellow-poplar obtained at the Forest Products Laboratory are also included. Compared with species of like density, possumwood is above average in all static-bending properties except stiffness in which it is si: below averag . It is average in hardness, t< s, and resistance to crushing Rept. No. R1902 -3- to a iH X) a co •P od ■p CO a o -P •H tH O rH Jtf ft U O H o h d S ft O (0 >i 3 CD - -P 3 to cj s Cn +3 o CO CO 3 *H -P T3 O ft I 2 CO -p CO -H co i a U Jh iH ■P O H CO ft O H h m a) oj ft a x> o •H P iH ft CO P ■P u O 0) ft CO C OJ oj a oj 3 (h h O o H oj 73 i O H OJ O t» > o 0) -P b fl 3 OJ •P -P co a •H O O o s M CO ^) ft > co < CVJ MJ O ON O O o o o -H- CO rC\ CO -3 oj OJ -P ■p a) •h .p .0 CO o o > " b co 3 co W O -— ft H| 13 «»> - — «. 3 u H <3 cr) CD s s 0) ft a tH p O 4) •H ft-3 i 5 Pi 0) > -H H H o u 'J O H iH H a -P 0)' >H CO 1 . CD 1 • OJ 1 OJ • I 5 H 3 V04H4- ojI o co ir\t— o • § fl «s r-h-iT\r- EH M CO • OJ to 1 tH Cm cd > ft O P t— O Q O O OHCOO CO a) • 13 Cd OJ ^J- lOi CO OJ • q ■H H A •H » CJ a fn •h ct) • O O Q O O OJ 00 co t*-co co t— .3 • CO ft a i (h . o o cd a •H CO H iH •H • o o o o o K^^t CO 00 lA co ft 3 O ed C In O +5 m CO • KN^J- CA ITS -* OJ OJ -H (0 E-< ftT* ft a i i o a i a •h i h -3 i -p o co C cd a) i a) ri p . •H CO CO H M 1 +J "H cd ft 3 to i a u a h h u I O Ofl • O O O O O CO HOVDN KN • J- J- J- J- ro ft OJ -H O 1 OJ ft H ft 3 ft-O 4-> 1 >-t O O' 1 P (hH o i co ft cd CO 1 OJ O O O O O co i t3 •1 ^ o\oj- -* CO 1 i-l •° J- rA m J- rr\ | ' M t-nl cd I C •1 O O O O O -° H V£> ON CO CA W i w Hi IT\ J& ITNlfN N^ 1 1 a i co m •H 1 3 cd >» o •H o o o o U 1 HHP o • ca r--=r t— >H 1 3 OJ iH o CO OHWH CO I n3 o » • ■\ «\ •* »k • 1 O Vl -H H ft ■H H H H O I 2 O -P • i tjca ■h i a a -p OJ i 3 i-t bo • o o o o o •H K> r- t^ CA CVJ h i a j3 c • J- V£> CVJ C— J" H I i-l co OJ CO •* * •* •* »s «! 1 k J3 h C 1 M jn -P ft CVJ CVJ fACVJ CVJ cd i S O co 1 CD P (3 1 CO 1 -rj o i oj u a •H 1 (h O -H • O O Q O O HOCOVO ^ CO 1 -P ft H •H CD 1 CO O • -* CA IPiON Os OJ 1 U H GO •s *s ^ •* •» h 1 h ft cd • H rH CVJ r-i H ft • 0J o ft a i ,o +j o D 1 *rl (8 a) H 03 OJ a 03 CO cd 3 a cp tJ oj I n a cd co -P CJ 3 3 oj i-i U P cd 6 CO g h 03 n +i 3 oj p > a co ft > CO < & hi a <-« Ao cd CO Ct) -: rH -9 M ■8 S CD CO ft a CH OJ O 03 •H •H CJ O iH i ft M ft •H ft a cd 3 b co 3 CD > n O M ^ CO CJ H -H ■P CO « rH h3 O ^^ ft tH I -H- « XI o 03 EH | ■P ft 0) Q co CVJ o CA H « "I -P ft X OJ K c-J and modulus of elasticity as determined by compression parallel to the grain; above average in shear, cleavage, and compression and tension perpendicular to the grain, and, below average in stress at proportional limit in compression parallel to the grain. In the tabulation it is compared with yellow-poplar which is of similar density. The two species are much alike in all measured mechanical proper- ties, with possumwood being slightly superior to yellow-poplar in all but stiffness as determined by bending. Seasoning Possunwood can be air dried at a fast rate without undue warping and checking. Early rapid drying tends to forestall the development of mold and stain which form rapidly on green material in warm weather. As indicated in table 2, volumetrio shrinkage of possunwood is low, 7»3 per- cent, which compares favorably with mahogany, 7»7 percent, and white pine, S.2 percent. The difference between shrinkage radially of 2. J percent and tangen- tially of h. 5 percent is moderate, indicating rather uniform shrinkage in these two directions. Longitudinal shrinkage of 0Jl8 percent does not exceed the limit of variation to be expected of wood characterized by interlocked grain. Table 2 Species Source : Shrinkage Radial ■ Tangential Longitudinal Volumetric Panama : Percent Percent 4.6 I Percent 0.26 : Percent Possumwood 2.5 i 6.k (Hura crepitans) Venezuela 2.S h.6 , •77 i 7.5 Surinam ; 2.7 . k.h J+2 : s.o Average : 2.7 i M M 7.3 Maho gany ( Sw ie tenia Central America 3-5 > h.S s ___ ; 7-7 macrophylla) 'Yhite pine (Pinus .United States : 2.3 6.0 ___ 3.2 strobus) J Durability Possumwood has been found to be fairly resistant to fungi and susceptible to damage by termites (Hj 27). Tests conducted at Yale (ll_), showed the wood to have resistance to decay by a white-rot and a brown-rot fungus ranging from nondurable to durable. Tests conducted by the Navy (l) on water absorption and weathering indicate that this wood compares favorably in both respects with Philippine and Central American mahogany. The tests at Yale (11_), however, showed possumwood as being somewhat inferior to Central American mahogany in resistance to water absorption. Rept. No. R1902 -5- V Uses The wood is used locally for common lumber for interior construction and car- pentry and in making dugout canoes, boxes and crates, and veneers and ply- wood. In Mexico, it is sometimes used for telegraph poles. It is considered too light and soft to withstand marring for use as a preferred cabinet wood. It rates as a cheap substitute for Spanish cedar ( Cedrela ). Since possumwood takes glue well, it could probably be used for cores tock, utility and face veneer, and millwork. Commercial Aspects An effort to introduce this wood into the American market under the name "Rakuda" was made by W. L, Kann, Pittsburgh, Pa., beginning about 1923 (17)« Anatomical Structure (19) Growth rings are indistinct to distinct. Pores vary from small to rather large in different specimens and are not very numerous. Vessel ends have simple perforations. Tyloses are fairly abundant, and light-colored gum deposits are common. Rays are uniseriate or locally biseriate, mostly less than 20 cells high, and nearly homogeneous. Ripple marks are generally absent. Rept. No. R1902 -6- Lirt of References 1 . Anonymous . 19uu. Habillo Wood as a Substitute for I ■ ; . . . - 'ivy Depart- ment, New York Naval Shipyard, Brooklyn, Kept. No. U5>6^J-1 . 2 . Anonymous . 19ii9. Select Rept. No. 9. Timber Development Association, 21 College Hill, London, E.C.h. 3. British Standards Institution. 19h8. Nomenclature of Commercial Timbers. Provisional Supplement to British Standards 881 & £89:19h6, PD8U1. London, 18 p. U. Brooks, R. L., Adamson, A. 1.'., Baker, R. E., and Crowdy, S. II. 19i|l. Durability Tests on Untreated Timbers in Trinidad. Caribbean Forester 2(3) : 101-119, April. £. Cooper, G« Proctor 1923. The Forests of Western Panama. Tropical V.'oods 16:1-9 > Dec. (School of Forestry, Yale University, New Haven, Conn.) 6. Cummin gs, Lewis A. 1929. The Forests of Venezuela. Tropical Yfoods l8:32-h2, June. 7. Daniel, H. 1936. Notas Sobre klguna: Euforbiaceaes. Boletm del Colepdo de n Jose (luedellin, Colombia) 37:3-11. 8. Dugand, Armando 193a. The Transition Forest of Atlantico, Colombia. Tropical V.'oods a 0:l-l u , Dec. 9. Dugand, Armando 1936. Nomina de las Maderas que se Emplean in Barranquilla par Construccion, Ebanisteria y Otras Obras. Bol. Municipal de Estadica, Ciudad de Barranquilla, u:2U:J40-li2, Feb. 10. Hernandez 16^1. "De Quauhtlatlatzin seu Arbore Crepitant i II" (The Tree is Figured), Thesaurus 88 (see Standley (20). 11. Hess, R. . , angaard, F. F. , and Dickinson, F. T . 19^0. Properties and Uses of TroDical V.'oods, II. Tropical V.'oods No. 97:1-132 (73-76). 12. Jaffe, r: . 0. 19u3. Hurain, a New Plant Protease from Hura Crepitans (Venezuela). Jour. Biochem. lu9(l):l-7, July. 13. Lamb, George I . 19a7. Foreign ^ oods: Hurawood. v .'ood Products £2(9) :22, Sept. la. Le Cointe, Paul 19h7. Irvores e Plantas Uteis. Amazonia Brasileira III, Sao Paulo, $06 p. Rept. No.JU902 -7- 15. Merker, C. \., Barbour, W. R., Scholten, J. A., and Dayton, W. A. 19U3. The Forests of Costa Rica. U. S. Forest Service, Washington, U8 p. 16. Pfeiffer, J. Ph. 1926. De Houtsoorten van Suriname. Amsterdam. 2UU p. 17. Record, S. J. 1938. The American Woods of the Family Euphorbiaceae. Tropical Woods 5li:7-hO(25-26)(with key). 18. Record, S. J. and Hess, R. V. r . 19h3. Timbers of the New V.'orld. Yale Press, New Haven, Conn., p. 160. 19. Record, S. J. and Mell, C. D. I92J4. Timbers of the Tropica America. Yale Press, New Haven, Conn., p. 37U-77- 20. Standley, P. C. 1923. Trees and Shrubs of Mexico. Contrib. U. S. Natl. Herbarium (Washington). 23, Pt, 3:6U5-U6. 21. Standley, Paul C. 1927. Poisonous Trees of Central America. Tropical Woods 9*3-7, Mar. 22.- Standley, Paul Co. 1928. Flora of the Panama Canal Zone. Contrib, U. S. Natl. Herbarium (Washington). 27:l-iil6, Jan. 23. Standley, Paul C. 1937- Flora of Costa Rica. Field Mus. Nat. Hist. (Chicago), Bot. 1938 Series 18:1-1616. 2lt. Williams, Llewelyn 1936. Wood of Northeastern Peru. Field Mus. Nat. Hist. (Chicago), Bot. Series 15:1-587, Dec. 25. Williams, Llewelyn 1939. Maderas Economicas de Venezuela. Bol. Tech. No. 2, Ministerio de Agri. & Cria. Caracas, 97 p. 26. Williams, Llewelyn 19li2. Exploraciones Botanicas en la Guyana Venezolana. Servicio Botanico, Ministerio de Agri. & Cria, Caracas, I168 .p. 27. Wolcott, George N. I9I4O. A List of Woods Arranged According to Their Resistance to the Attack of the "Polilla," the Dry-wood Termite of the West Indies (C ryptotermes brevis Walker). Caribbean Forester l:Ii:l-9, July. UNIVERSITY OF FLORIDA Kept. No. R1902 -8- 3 1262 08927 3576