EXPERIMENTS WITH TREE SEEDS. - 141 
is likely — the vigour of the original seedling materially in- 
fluences the vigour of the resultant tree, the careful selection of 
the seed, as regards size, becomes a matter of the very highest 
importance, 
For a pure wood, selection of seed is of less importance, so long 
as the seed employed contains a fair proportion of large individuals. 
Fie. 4.—Plants produced by large, medium, small, and very small Acorns, 
in the order given. 
When a wood is stocked with seedlings all of the same species 
and of similar age, though varying somewhat as regards size and 
vigour, competition for air, light, and growing space generally, 
will at once begin, with the result that in a few years the vigorous 
plants will be spreading their crowns more or less above the level 
of their neighbours, while the weaker ones will be partially over- 
