SILVER FIR 



G.N. 8315 



SILVER FIR 



Abies pectinate DC. Coniferae. Abietineae. 



A soft wood, light in colour and in weight resembling Spruce, from which 

 it is difficult to distinguish. This is more especially the case when the 

 resin-canals (vertical) are rare in the Spruce. Although plainly striped, 

 the difference in colour of the Spring and Autumn wood is not very 

 great. Smell when worked, none (dry wood). Lustre crystalline or 

 satiny. 



Reaction of watery extract with potash, greenish: with perchloride 

 of iron, brown precipitate (Constant?). 



Structure. Resin-canals absent. Occasionally .traumatic canals occur, 

 but these are then in arcs of some length tangentially and the component 

 canals are of various sizes and irregular in appearance. 



Rays of one kind only (the smaller) uniseriate. In tangential section 

 they are seen to be up to about 30 cells in height or less. At times the 

 rays seem to be superposed one over the other in a vertical direction as 

 though on the point of being split into two or more. No tracheids in the 

 rays. 



Pits in the cross-field, several, small; occupying very little of that 

 area. 



Pith minute. 



The shavings are crisp to the touch. 



May be confused with: 



Spruce (resin-canals, especially 

 the horizontal canals in the rays, 

 present: tracheids in the rays). 



Weymouth Pine (one or two 

 large pits in the cross-field: resin- 

 canals abundant). 



Sapwood of Scots Pine (as Wey- 

 mouth, but only one large pit). 



May be distinguished by: 



Absence of both kinds of resin- 

 canals. No tracheids in the rays. 



Two or several small pits in the 

 cross-field. No resin-canals. 



As above. 



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