HERMAN H. CHAPMAN 35 



or tolerance. Such species are forever on the move. As- 

 pen almost never succeeds itself, unless the old stand of 

 aspen is burned off. In the spruce regions, much of the 

 spruce on mountain slopes gets started under aspen and 

 birch which are the first trees to spring up on burns, and 

 this birch and aspen grows old and dies, leaving the young 

 spruce, almost as old as they are, to live for 200 years 

 longer. But in the meantime another burn or blow down 

 has occurred within a mile or two, and is at once seeded 

 up to aspen from the first stand. 



The Seed Bed and the Seedling. Many times we find 

 seed trees and seed, but very few seedlings. There is 

 always a reason for this to be found in the condition of 

 the seed bed. The seed will not germinate without mois- 

 ture, and it must be able to take root. Very dry soils, 

 exposed to the sun, prevent the starting of tender seed- 

 lings like hemlock. Hard-baked soils make it impossible 

 for the root to penetrate, and we find acorns with a long 

 radicle, rolling about on the surface, and soon drying up, 

 while amongst leaf litter they find easy access to the soil. 

 But pine seeds cannot grow at all on leaf litter, and very 

 seldom in grass, which holds the seed up off the soil and 

 dries it out. So it is an accepted fact that for most pines 

 we must burn the ground in order to get good reproduc- 

 tion of seedlings. Some such considerations always ex- 

 plain the lack of seedlings if seed is present. But the mere 

 starting of seedlings does not insure their survival. Here 

 is where the needs of the species for light come into play. 

 Many more seedlings die for lack of light under old trees, 

 than survive. A seedling will live a year or two in shade, 

 but if this shade continues, it will succumb. Trees be- 

 gin to bear seed at ages varying from 6 to 7 years in the 

 case of Jack pine to 50 and 60 years and the seed is al- 

 ways borne most abundantly by the trees with the great- 

 est opportunity of distributing it to good advantage the 

 open grown trees or those on the edges of stands, or over- 



