PRACTICAL ARBORICULTURE 285 
Basswood has averaged a gain of 3.28 inches circumference per annum. 
Yellow poplar, 2.7 gain per annum. Silver maple, 5.8 gain, growing in four- 
teen years to be 25.8 inches in diameter. 
The Cottonwood has gained 7 inches girth each year since it was planted. 
Birches have gained from 3 to 4’ inches per annum. Ash, 2% inches gain. 
Mulberry, 4 inches gain, the same as Locust. The Catalpa is 15 inches 
diameter, a gain of 3.4 girth each year. 
The Oaks have gained 2.4 each year. Sweet gum in twenty years gained 
2.6 inches. White Elm gained 3.2 inches girth, Hickory gained 2.4 inches per 
annum in the twenty years, while Chestnut made 3 inches additional each 
year. 
The foregoing tables prove beyond a question that almost every species 
of our American woods can be grown to a merchantable size, and become 
a profitable investment within a quarter of a century, many trees increas- 
ing one inch diameter each year of its existence under most unfavorable situ- 
ation and conditions. 
With fairly good soils and thorough cultivation, planted more closely 
to prevent the formation of turf, and more especially if it be a renewal of 
an old forest, these records should be greatly exceeded. 
