3 o THE ANATOMY OF WOODY PLANTS 



the examination of the fibrous structures of the wood of the oak. 

 Fig. 23 gives a general view of the organization of the wood in a 

 red oak (Quercus rubra) . Clearly it shows a much higher degree of 

 complication than is found in the ligneous tissues of a conifer or 



FIG. 23. Wood of the red oak. Explanation in the text 



forms still lower in the scale. The wood is crossed by conspicuous 

 bands of storage tissue, the large rays so characteristic of the 

 organization of oak wood. In the squares bounded by the annual 

 rings and conspicuous rays lie the remaining structures. Of these 

 the vessels are most outstanding and are very large at the beginning 

 of the annual zones, becoming much smaller in caliber in the 

 later-formed wood. The vessels are imbedded in radially directed 



