JOURNAL OF FORESTRY 



Vol. XVII JANUARY, 1919 No. 1 



MAHOGANY AND SOME OF ITS SUBSTITUTES ^^,^^ 



A Descriptive; Key Based on the Gross and Lens Characters "^^^ ^i 



BOTANI 



By Samuel J. Record ttAM>l 



Professor of Forest Products, )'a/r Unkrrsity 



This key embraces most of the woods known to the trade as "mahogany" or 

 used as a substitute for the wood to which the name rightly belongs. A few of 

 importance, particularly of African origin, have been omitted because authentic 

 material was not available to the author. Some others have been excluded be- 

 cause of their insignificance. Representatives of 13 families and 27 genera are 

 described; 11 genera belong to the mahogany family Meliacese. The only equip- 

 ment necessary to use the key is a very sharp pocket knife and a small hand lens 

 magnifying from 10 to 15 times. Care should be taken that the cuts made, espe- 

 cially on cross section, be very smooth, otherwise the structure will be obscured. 

 The two main divisions of the key are based upon the visibility or invisibility of 

 the rays. When doubt exists on this point, as is likely where the rays are very 

 near the limit of vision, the user may need to try both divisions. In three such 

 cases the descriptions are duplicated. This key was prepared in connection with 

 a course in tropical woods. Material assistance was rendered the author by his 

 students, especially Mr. Allen B. Engle and Mr. I. Laurance Lee. 



Contribution from Yale School of Forestry, No. 2. 



A Rays visible on cross section without lens, though often very fine. 



a Resin ducts present, usually appearing under lens (on cross section) as 

 small white dots in few to many tangential lines which are sometimes con- 

 centric and rather widely spaced as though limiting growth rings. < Pores 

 readily visible; often subdivided; gum deposits absent; tyloses present or 

 absent ; white substance sometimes present in dense specimens. Wood 

 parenchyma associated with resin ducts and sometimes in wavy tangential 

 lines in certain species; not prominent on longitudinal surface. Rays con- 

 spicuous on radial surface, usually considerably darker than the fibers. 

 Ripple-marks absent. Woods odorless. Color variable from yellowish or 

 pinkish to reddish-brown or deep brownish-red. Density and texture 

 widely variable. "Philippine Mahogany," "South P.\cific Mahog.xny,'' 

 Lauans, Tanguile, Bat.^an. 



a^ Woods comparatively heavy, hard and fine-textured. T.\nguile, B.\- 



T.AAN : Shorea polysperina, et al. (Dipterocarpacese ). 

 b^ Woods light, soft and coarse-textured. 



a* Color reddish or pinkish. Red L.^uan : S. ne\groseitsis. 

 b^ Color yellowish, grayish or nearly white. Almon, White Lau.\n : 

 S. cximia, Pentacme spp. (Dipterocarpaceae). 



