288 BOTANICAL GAZETTE [APRIL 
new forest than in the old. So if any other tree, lodgepole pine for 
example, has more seeds than the others, it will increase in numbers 
in the new stand that is formed. So far as its relation to restocking 
a burn is concerned, a tree that does not produce seeds might just 
as well not exist at all. 
This leads naturally to another modification of the hypothetical 
case, in which the forests that surround the burn have only one or 
two species instead of anumber. The result will be that these species 
are likely to be the only ones found in the burn. Such a condition 
is seen in fig. 20, where the forest that surrounds the clearing is com- 
posed mostly of western larch and lodgepole pine, and these species 
are the predominating ones in the new growth. Fig. 21 shows a 
clearing surrounded principally by lodgepole pine and Engelmann 
spruce, which are almost the only trees present in the new stand. 
Again, fig. 22 shows that bull pine, western larch, and Douglas spruce 
are present in an opening in a mature forest of these species. Another 
explanation for this, however, is that the area is situated on the border 
of the meso-xerophytic region where probably no other species could 
exist, even if their seeds were present. 
This leads to still another modification of the hypothetical case. 
Assuming that the seeds of all the species are present, it is highly 
improbable that they would find equally favorable places for germina- 
tion. The case just cited (fig. 22) is an instance of where all except 
western larch, Douglas spruce, and bull pine are ruled out. If the fire 
burnt out an Engelmann spruce stand surrounded by a less swampy 
region in which Engelmann spruce, lowland fir, silver pine, Douglas 
spruce, western larch, and lodgepole pine were present, only Engel- 
mann spruce and lodgepole pine would be able to restock it, for 
these are the only species that could grow in the swampy situations. 
An instance of such restocking was noted near the head of the bay- 
like area of meso-hydrophytic forest southwest of Ross Lake. 
Still other conditions of reforestation remain to be expla 
Taking the hypothetical area that has been restocked with the seed- 
lings of all the trees in the surrounding forest, and assuming that 
the young growth is approximately fifteen years of age, the only 
species of this young growth that would have fruit is lodgepole pine: 
The cones on this pine would be more or less abundant, and on 
ined. 
