THE STRUCTUKE OF WOOD. 



29 



some, as ash, the tracheids are wanting; apple and maple have no 

 woody fiber, and oak and plum no fibrous cells. 



This recital is enough to show that the wood of the broad-leaved 

 trees is much more complex in structure than that of the conifers. It 



DWME7ERS 



=*PITM RAYS 



CR055*5ECTfOtt 



l DIAMETERS 



PfTHR 



-PORE 

 RADIAL SECTiOh 



TAN6EMT1AL SECTION 



RING-POROUS WOOD (WHITE ASH) 



Fig. 20. 



is by means of the number and distribution of these elements that 

 particular woods are identified microscopically. See p. 289. 



Ring-porous woods. Looking thru the microscope at a cross-section 

 of ash, a ring-porous wood, Fig. 20 : 



(1) The large round or oval pores or vessels grouped mostly in 

 the spring wood first attract attention. Smaller ones, but still quite 



