THE ROMANCE OF OUR TREES 



low, scrubby growth. On seacoasts the wind has 

 full play and the same effects are seen; also on broad 

 plains and plateaux. In short, the effect of strong 

 winds everywhere is to retard tree-growth, and so it 

 comes about that on the coasts, open plains, plateaux, 

 and on the summits of mountains dwarf, stunted 

 forms of tree-growth are common. These adapta- 

 tions to environment, or ecological forms, as they are 

 technically called, are often very distinct from the 

 parent types, but if raised from seeds and cultivated 

 under normal conditions they usually revert to their 

 ancestral forms. For example, the upper slopes of 

 Mt. Fuji in Japan are clothed almost exclusively with 

 dwarf Larch which is merely an ecological form of the 

 type that in the forests which cover the base and lower 

 slopes of the mountains grows fully 80 feet tall. Near 

 its altitudinal limits the gnarled stems of this dwarf 

 Larch fairly hug the lava and cinders. Some twenty- 

 eight years ago seeds from this prostrate form were 

 sown in the Arnold Arboretum but the plants raised 

 from them have rapidly grown into tall trees, and are 

 now quite indistinguishable from others raised at the 

 same time from the typical Larch-tree of the lower 

 forest-zone. Of course there are genuine dwarf 

 Larches which cannot be persuaded to grow into any- 

 thing else, no matter how they are propagated; but in 

 general the stunted forms of tree-types have to be 

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