PLANE TREE 



G.N. 6692 



PLANE TREE 



Platanus orientalis Linn.: synonym, P. acerifolia. Willd. Platanaceae. 



A whitish, ecru or brown wood with a remarkably conspicuous though 

 dull silver-grain. Medium weight and hardness. Sapwood merges 

 gradually into the darker central wood. 



Transverse section. (Note. Under microscope in transverse section, 

 this wood is indistinguishable from Beech.) Boundaries sometimes very 

 clear, but sometimes not traceable over large areas. Contour crenate 

 (i.e. arched outwards) between the rays (lens). 



Parenchyma not visible with lens. 



Vessels just visible? very small, diminishing in size though but little. 

 outwards to the boundary: crowded (lens) throughout the ring. 



Rays large, very numerous and close but inconspicuous (unless wetted) 

 on account of their lack of lustre : nodose where they cross the boundaries. 



Radial section. Silver-grain very conspicuous though dull, occupying 

 a large proportion of the surface. Boundaries hardly traceable. 



Tangential section. A great contrast to the radial : the rays produce a 

 somewhat matt surface, the individual rays being obscure though still 

 quite visible. Small (uniseriate) rays very rare. 



May be confused with : 



Beech (rays in tangential section 

 widely separated, bright and dis- 

 tinct, many small ones: ring- 

 boundaries, sharp in all sections). 



Alder (large rays rare and 

 widely separated. Silver-grain, 

 scanty, pale and straggling). 



Western Plane-tree (boundaries 

 of the rings very sharp every- 

 where). 



May be distinguished by: 



Rays in tangential section, 

 though more abundant and closer 

 together, are dull and produce a 

 matt surface: small rays rare. 

 Ring boundaries obscure in all 

 sections. 



Rays abundant and close to- 

 gether in all sections. 



Boundaries variable, sometimes 

 fairly definite but usually indis- 

 tinguishable over long radial dis- 

 tances. 



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