286 BOTANICAL GAZETTE [APRIL 
condition is approximated; of course the proportions are not exactly 
the same in the old and new stands (fig. 20). Granted that any one 
of the species in the young forest grows more rapidly in its youth 
than the others, other things being equal it would gain an ascendancy 
over its neighbors, and in the forest approaching maturity it would 
have more representatives than in the old forest. As already shown, 
lodgepole pine bears exactly that relation to Douglas spruce and 
a clearing Sur- 
Fic. 20.—Young growth of lodgepole pine and western larch in ; i 
rounded by older trees of the same species, both of which have seed-bearing trees; 
other plants are dwarf maple and a willow, both of which sprout from old stumps; 
fireweed is also a characteristic plant.—Photograph by PRAEGER. 
western larch at least, and probably to the other species, though no 
measurements were taken for them. In the new forest thus estab- 
lished, lodgepole pine has made a gain on the other species. How- 
ever, it reaches maturity sooner than the others, and in the old a 
it is the first to drop out in the struggle for existence, So that while in 
the middle-aged forest it may have had some slight advantage, 1 
loses this and often is entirely eliminated from the mature stand. 
