IDENTIFICATION OF COMMERCIAL WOODS 



SIDNEY L. JOHNSTON, '18, and WILLIS G. CORBITT, '18 



Purpose 



THE purpose of this study is to determine if possible the relative ac- 

 curacy with which the most common commercial woods can be cor- 

 rectly identified by the average person without previous training in 

 wood identification, and at the same time to learn which species are 

 the most often incorrectly identified and the reason for the mistakes, 

 whether due to a similarity in structure^color, odor or merely gross blunder. 



Method. 



The data for this study were compiled from examination papers turned 

 in by twenty-seven students in wood technology at the University of Wash- 

 ington, representing the work done during the beginning of two different 

 semesters. The students in each class were inexperienced in wood identi- 

 fication, having had no previous systematized training along that line other 

 than a brief laboratory study of type specimens just previous to the exami- 

 nation. 



The specimens were numbered and then given to the students who 

 examined them with a hand lens or the unaided eye and then wrote on 

 the examination papers opposite corresponding numbers what they con- 

 sidered the correct common and scientific names. In many cases un- 

 common woods were passed out with the specimens in order to test the 

 students' ability to distinguish between those that were similar in color 

 and texture. For example, Shii, a foreign species, might easily be mis- 

 taken for maple. These specimens were termed "ringers", and if judged 

 as such by the student the identification was considered correct. In ob- 

 taining the total number of correct and incorrect identifications for each 

 species those due to "ringers" were eliminated from the accompanying 

 table. 



The specimens submitted for examination varied in size and shape 

 from a twelve-inch plank to an empty thread spool. In certain instances 

 the samples were stained or kept in contact with odorous woods previous 

 to examination in order that the student, to judge correctly, would have 

 to examine the structure of the wood carefully. In most cases, specimens 

 once identified by the students were stored away, to avoid the liability of 

 recognition due to students becoming familiar with the physical form or 

 shape of the specimens. 



Results. 



The accompanying table is almost self-explanatory, but a few com- 

 ments on the results as tabulated may help to emphasize the essential fea- 

 tures of the study and make clear the reasons for the conclusions. 



The species as tabulated follow in the order in which they are classi- 

 fied in Record's "Economic Woods of the United States." As in all scien- 

 tific classifications, the woods are grouped according to certain similar 

 characteristics, the details of which need not be explained here. It will be 

 noted, however, that the fifty-three species are divided into three main 

 groups, the non-porous, ring-porous and diffuse-porous woods. These 

 terms are deemed self-explanatory and will therefore receive no further 

 Uscussion. 



A careful study of the accompanying table will disclose many inter- 

 jting facts, only a few of which will be enumerated. Referring to the 

 m-porous woods, one will see that there are seven species having a per- 



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