February 25, 1917 



■&2* Plea for Closer Discrimination 



Editor's Note 



This article was written by Arthur Koehler, expert In wood identification at the government laboratory, Madison, 

 Wis. It Is a plea for more discrimination in the use <St the words "grain" and "texture," with reference to wood. The 

 plea will strike a responsive chord among lumbermen and wood users who have many times been tempted to throw up 

 their hands in despair because of the loose and promiscuous manner In which words are used which should have ex.act 

 meanings when applied to wood. The suggestion that the width of the annual ring should never be confused with 

 grain or texture is to the point and is easy to remember. 



The word "grain" has probably a wider latitude of meaning than 

 auy other term in the lumber trade. It is used to express almost every 

 conceivable characteristic of wood which can be judged with the eye. 

 As commonly used, it is made to include the width of the annual rings 

 — coarse or fine-grained; the size of the pores — open or close grain; 

 the distribution of the denser and softer elements — even and uneven 

 grain ; the figure, which is dependent on color variations and differences 

 in the reflection of light, — beautiful grain, banded grain, silver-grain, 

 or without grain ; the direction of the fibers — straight, spiral, diagonal, 

 cross, wavy, curly, or bird 's-eye grain ; the character of the surface 

 after the wood is dressed — rough or smooth grain; and the plane in 

 which lumber is cut — flat, edge, vertical, or comb grain. "Texture" 

 is often used synonymously with ' ' grain ' ' except where the direction 

 of the fibers, the plane in which the lumber is cut, and the figure are 

 concerned. Obviously, such diversity of meaning leads to confusion, 

 and in fact it leaves the words "grain" and "texture" meaningless 

 unless explained. These terms should be used with greater discrimina- 

 tion so as to give them a more definite meaning. 



The word "grain" is commonly used as indicating the width of the 

 annual rings — wide-ringed wood is called coarse-grained, and uarrow- 

 ringed wood fine-grained, but a little reflection will show that this 

 meaning is inconsistent. For instance, who would call white pine or 

 the gums coarse-grained no matter how wide the annual rings were; 

 or can a wood with large pores like oak, or chestnut, ever be called fine- 



grained? (Compare figures 1 and 2.) If the wide annual rings of lob- 

 lolly pine were composed entirely of either soft springwood or dense 

 summerwood so that the limits of the rings would be obscure it surely 

 would not be called coarse-grained. Furthermore, with this meaning 

 given to grain, a tropical wood without definite annual rings could be 

 neither coarse nor fine-grained. 



It is suggested that the width of the annual rings be expressed as 

 narrow, medium, or wide-ringed, or as slow, medium, or rapid growth, 

 or, to be more definite, as a certain number of rings per inch ; and that 

 the word "grain" be given a more restricted meaning. Surely this 

 could cause no misunderstanding, for anyone familiar with lumber 

 knows what a wide or narrow annual ring is. 



"Grain" is also used with respect to the relative size of the pores 

 or other elements and their distribution, as coarse grain and uneven 

 grain. This would be a good use for the word "grain," but "tex- 

 ture" is also used in the same way, and "grain" is consistently and 

 persistently used with respect to the direction of the wood fibers. It 

 is, therefore, suggested that the relative coarseness or fineness of the 

 structure of wood (not annual rings) be designated as coarse, medium, 

 or fine texture, and the distribution of the coarser and finer elements 

 as even and uneven texture. Oak, accordingly, would have a coarse, 

 uneven texture; mahogany a medium, even texture; and yellow pine a 

 fine, imeven texture. (See figures 1 and 2.) In fact, all coniferous 

 woods have a fine texture, but this may vary; for example, pencil 



FIG. 1— CROSS SECTION BLACK GUM SHOWING TWO WIDE ANNUAL 



RINGS. THIS CANNOT BE CALLED "COARSEGRAINED" 



BUT RATHER WIDE-RINGED, WITH FINE, 



EVEN TEXTURE 



PIG. 2— CROSS SECTION OF WILLOW OAK SHOWING SIX NARROW 

 ANNUAL RINGS. THIS CANNOT BE CALLED "FINE- 

 GRAINED" BUT RATHER NARROW-RINGED WITH 

 COARSE. UNEVEN TEXTURE 



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