SWEET CHESTNUT G.N. 6710 



SWEET, SPANISH OR EDIBLE CHESTNUT 



Castanea saliva Mill.: synonyms, C. vesca Gaertn. ; C. vulgaris Lam. 

 Fagacese. 



A ring-porous, brown w&od of uniform colour, coarse grain and medium 

 hardness and weight. A heartwood tree : sapwood narrow. 



Transverse section. Boundary, the pore-ring. 



Parenchyma of two kinds, (a) (vasicentric) imbedding the vessels at 

 times into radial streams and at others nearly absent. It is usually 

 visible at arm's length, but it is exceedingly capricious in its appearance 

 [for (b) see below]. 



Vessels very large and prominent especially in the pore-ring. In the 

 Autumn wood they are in radial streams, sometimes branching and 

 slightly oblique to the radius: they leave wide, empty spaces between 

 the streams as in the Oak. The vessels diminish very much in size in a 

 regular manner, outwards to the boundary of the ring. Thyloses rare, 

 if any. 



Eays very fine (lens), numerous and regular in size and spacing, at 

 intervals of about the width of a large vessel apart. 



Radial section. Boundaries (pore-rings), very conspicuous as coarse 

 (often sinuous) bands of vessels. Rays very obscure, generally invisible 

 except with lens. Parenchyma (b) concentric in zones of one cell wide 

 visible only in transparent section (microscope). 



Tangential section. Boundaries, the coarsely-fringed loops; rays just 

 perceptible (lens) when wetted. 



May be confused with: May be distinguished by: 



Oak (large rays which show up Rays visible only with lens in 

 as a prominent silver-grain in transverse and tangential sections 

 radial section, and in tangential and doubtfully with the unaided 

 section as brown, spindle-shaped eye in radial section, 

 lines of 1 inch or more in height). 



Ash (vessels in small arcs or Vessels in radial streams nearly 

 angles in the Autumn wood). always shown up by light-coloured 



parenchyma. 



Elms, Robinia, Mulberry, Ail- As above, 

 anthus, Gleditschia (vessels in con- 

 centric lines, arcs, angles, etc., at 

 least in the Autumn wood). 



Teak (vessels isolated in the As above. 

 Autumn wood). 



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