PRINCIPLES WHICH GOVERN COMPOSITION OF STAND 69 



age classes depends largely upon the species and the site. Thus 

 European larch and sugar maple form an excellent uneven-aged 

 mixture in southern New England. The regeneration is started 

 as pure larch, and the maple is brought in from 20 to 30 years 

 later or when the stand becomes too broken to maintain an 

 acceptable soil cover. Oak and hemlock, oak and sugar maple 



FIG. 14. An overwood of oak with an underwood of beech. Germany. 



or beech, walnut and sugar maple, ash and beech are often found 

 growing together under natural conditions and should form ex- 

 cellent uneven-aged mixed stands in artificial reproduction when 

 the intolerant species are regenerated some years in advance of 

 the tolerant ones. Oak and beech are frequently grown in un- 

 even-aged mixtures in Europe (Fig. 14). 



11. Special Considerations which may Determine the 

 Species in the Mixture 



In some instances market considerations and the relative 

 freedom of certain species from external sources of injury may 

 overbalance silvicultural considerations and determine the best 

 species for the mixture. An even-aged mixture of white and red 



