316 THE CANADIAN NATURALIST. [Vol. X, 



may be of less width, and the 160 acre tract subdivided by sub- 

 stituting inside belts of such width that the land planted may 

 equal J or 4 of the whole area ; or the plantings may be com- 

 meucod two or three rods wide upon the north and west sides of 

 the land, and further extended year by year as the means of 

 the planter will permit until the maximum area is completed. 



The first planting of trees may be profitably composed of such 

 species as are indgenous to the locality, such as box, elder, Cot- 

 tonwood, soft maple, ashes, white and golden willow, European 

 alder, cutalpa, locust, butternut, black walnut, hickory, birches, 

 larch, hardy evergreens and other species of trees as may be 

 adapted to the soil and locality. 



In after years, when the first planted trees become of sufficient 

 size to afford shelter, other species considered of doubtful adap- 

 tation, or too tender to endure the climate without protection, 

 may be planted inside of the shelter belts already established, 

 and perhaps prove useful and remunerative to the planter. 



If it be conceded that all things considered, the shelter-belt 

 form will promote the increase of insectivorous birds; modify 

 electrical conditions; lessen the evaporation of moisture from the 

 soil ; retard the velocity of surface winds ; cool the earth and 

 atmosphere in the summer; raise the winter temperature; in- 

 crease the volume of atmospheric moisture ; lessen blizzards in 

 the north ; lessen the liability to drifting soil and snow and miti- 

 gate the destructive efi"ects of tornadoes and cyclones ; make the 

 soil more uniformly productive, and thus make the great plains 

 the grazing ground of countless flocks and herds, and become the 

 granary of the continent; our obligations to ourselves, to our 

 country and to untold millions of the human race yet unknown, 

 will be fulfilled only where large belts of forests are on these 

 Plains. 



The establishment of a general shelter-belt system of forest 

 planting for the great plans cannot be inaugurated too soon. 



Individual eff'ort in this direction, without the encouragement 

 of wise legislation on the part of the respective Governments, 

 will be isolated and the results too limited and too remote to be 

 appreciably beneficial, hence the necessity of legislative action. 



If history's teachings are true criteria, the wealth, power and 

 prosperity of nations largely depend upon a successful agricul- 

 ture ; but a permanently successful agriculture cannot exist 

 \vithout the aid of a wise system of forest economy. A large part 



