PEAR TREE G.N. 2074 



PEAR TREE 



Pyrus communis Linn. Rosaceae (Pomoideae.) 



A diffuse-porous wood of uniform structure : colour, brown to reddish- 

 brown: rather hard and heavy. Sapwood not clearly differentiated 

 from the heart. 



Transverse section. Boundary a line of contrast in the density of 

 successive rings. 



Parenchyma not visible with lens: dispersed amongst the fibres. 



Vessels small (lens), apparently crowded throughout the ring: dimin- 

 ishing considerably and regularly in size from the Spring to the Autumn 

 wood. They occupy practically the major part of the section. 



Rays fine but yet visible, numerous, at nearly regular intervals of the 

 width of a large vessel apart: brown and lighter in colour and brighter 

 than the fibres: multiseriate. 



Radial section. Boundaries scarcely visible as are the vessels also. 

 Rays, rather prominent, narrow, brown flakes occupying about half the 

 surface. No spiral thickenings nor grids. 



Tangential section. As the radial, but the boundaries are rather clearer 

 yet inconspicuous. They are feebly fringed indicating slightly larger 

 vessels at this point. Rays indistinguishable even with lens when wetted. 



Watery extract, rich red. more intense than the colour of the wood. 



May be confused with : May be distinguished by: 



White Poplars (P. alba} (grain Grain very fine: rays multi- 

 medium coarse, lustre silky, rays seriate, 

 uniseriate). 



Willows when dark-coloured and Medium heavy weight: great 



dense (much lighter in weight, rays solidity: multiseriate rays: vessels 



uniseriate: reaction of watery ex- occupy practically the whole of 



tract with perchloride of iron, the ring uniformly. Reaction with 



brown). perchloride of iron, olive. 



Alder when wide rays are absent As above. Watery extract, rich 



( weight rather light : vessels tending red . 

 to a radial arrangement and dis- 

 tinctly less numerous in the Autumn 

 wood. Watery extract pale brown 

 or nearly colourless^. 



Mountain Ash and Apple [watery Watery extract rich red. 

 extract pale yellow (citron)]. 



Other species of Pyrus. No certain characters beyond 



general appearance. 



12 



