THE TIMBERS OF COMMERCE 



p. 68. Hartig (42), pp. 28, 41. Schwartz, p. 479. Wester- 

 meier, p. 59. Holtzapffel, p. 86. De Mornay (70), p. 98. 

 Mathieu (69), p. 392. Wiesner (131), L. 12, p. 887. 



Colour. White or reddish-white. A sap-wood tree. Heart- 

 wood only in old trees and then apparently caused by disease. 



Anatomical Characters. Transverse section : — 



Pores. Need lens, size 5-6, some variation, decreasing to- 

 wards the outer side of the ring, in which they occupy less space : 

 numerous, 160-180 per sq. mm. : many subdivided or in radial 

 groups of as many as 12 : they are collected into a tree-like 

 arrangement. 



Rays. Clear, two sizes. The larger compound, size 2, broad, 

 rarely less than 1 mm. apart : swelled apparently at the junction 

 with the ring-boundaries : very long, tapering inwards only : 

 tissue dense and lax alternately, as though fine rays were com- 

 pacted into a large one by softer tissue : brown. Small rays 

 very fine, dense and slightly avoiding the pores. 



Rings. Very clear. Boundary, a line of contrast between the 

 dense Autumn wood poor in pores and the porous Spring wood : 

 contour convex outwards between the rays (crenate). 



Soft-tissue. Not visible with lens : fine wavy concentric 

 lines. 



Flecks. Rare : brown : in the late Autumn wood. 



Pith. Three-lobed: brown: i-i| mm. wide. 



Radial Section. Pores needs lens : fine, isolated scratches 

 except where a radial group is cut exposing several together. 

 Rays, inconspicuous, almost without contrast with the ground. 

 Rings appear as faint fine lines and the pith as a soft brown 

 band. 



Tangential Section. As the Radial, but the pores are much 

 less prominent and the rays appear as lines of considerable 

 height, about f inch : they can best be estimated immediately 

 under the bark. 



Type specimens from trees known before felling. 



No. 196. OAK (European). Quercus Robur, var. 



sessiliflora, Sm. and var. pedunculata. Ehrh. 



Plate XIV. Fig. 125. 



Natural Order. Cupuliferse. 



Alternative Names. Many, derived from the place of origin 

 or port of shipment, such as Memel, Riga, Stettin, 

 Danzig, etc. European White Oak in the U.S.A. (12). In 

 France Q. pedunculata is called variously Chene blanc (Gironde, 

 Landes, Picardy) : Chene a grappes, C. femelle, Gravelin : Chagne 

 (in the South) : C. noir (Blasois). Q. sessiliflora is called Chene 



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