CHAPTER VI: HOW TREES ARE MULTIPLIED 



Nature begrudges man all the land he has cleared of forests, 

 and if he relaxes his vigilance — lets a field lie fallow a year or two — 

 the forest begins to encroach, and takes it back. Every year 

 trees flower and fruit, and young saplings come up wherever there 

 is room and a chance in the woods. But here there is crowding 

 and struggling even among the large trees, and the saplings die 

 unless they can live under the shade of larger trees. 



I. THE NATURAL WAY 



The fortunate trees are those with abundant seeds, so light 

 or so winged that they can sail off on the winds and fall in new 

 places less crowded than the forest. The birches have such 

 seeds — little heart-shaped discs with thin, papery webs on their 

 edges all around. The pencil-like cones are packed with hundreds 

 of these seeds, and the trees hang full of cones. What wonder, 

 then, that birches so often follow in the wake of the lumbermen 

 in New England woods. Pines and the other narrow-leaved 

 evergreens are known by their cones. Have you ever shaken or 

 beaten the seeds out of an opening cone of white pine? This is a 

 typical conifer. The heavy brown seed has a wing by which the 

 wind carries it. That very field now grown up to birches was 

 once covered with virgin forests of pine. The neighbouring 

 woods scatter pine seeds with birch and many other kinds. The 

 birch gets the start. But in a few years you will see the little 

 pines coming up in the shade of the birches. The "nurse trees" 

 are short lived; they give way in time, and a pine forest follows 

 the brief sway of the birches. 



Why does poplar follow pine woods in many places? Note 

 the poplar trees in early June. They are discharging seeds from 

 long strings of green beads, burst open and turning brown. A 

 puff of cottony substance, light as down, encloses each minute 

 seed. There are millions on every tree. Wafted forth, these 

 seeds lodge all over the neighbourhood. The cleared ground 



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