102 



Trees, Stars, and Birds 



examining patterns in 

 other woods that show 

 distinct annual rings. 



Patterns in oak. In 

 oak the conspicuous 

 patterns in the wood 

 are due to the wide 

 pith rays as well as to 

 the annual rings. The 

 rays appear as light 

 spots, or "mirrors," in 

 the finished wood. 



A tangential section 

 exposes only the edges 

 of the rays, and a board 



mUSt be Cut b Y a radial 



section in order to show 

 the broad sides of the 

 rays. The rays are 

 very thin and the saw usually passes in and out 

 through them as it goes through the wood, so that 

 you will see only irregularly shaped portions of them 

 showing on the surface of the board. In some 

 places, however, you may find a ray running for some 

 distance across or along, the board. In a board 

 that has been given a golden oak finish the large 

 tracheae will show as dark, fine grooves in the wood 

 and the pith rays as light spots and bands. The 

 dense bundles of wood fibers, which form the greater 

 part of the wood, have an intermediate brownish 

 tone. 



U. S. Forest Service 



FIG. 64. Curly cherry. When the knots 

 are cut through, the annual rings in them 

 make patterns like those shown in Figure 63. 



