PLANTING AND CAKE OF TREES 133 



be left unpaved around each tree unless the roots may extend 

 beneath the sidewalk and make use of the adjacent lawn or yard 

 as a feeding ground. Sometimes trees have been planted in soil 

 that has-come from excavations and the only means of correcting 

 such a condition is to remove as much of the soil as possible from 

 around the roots and substitute for it some rich garden soil, or a 

 liberal supply of well-rotted stable manure may be mixed with the 

 soil already about the roots. 



Poor drainage is often responsible for much injury. Where the 

 soil-water comes near the surface, the roots are prevented from 

 entering deeply into the soil. Trees that have been blown down 

 and those having crooked and leaning trunks, usally have been 

 grown under such conditions. Such trouble can be avoided only 

 by proper under-draining. 



RENOVATION OF TREES 



The natural age limit — Knowing that some trees have reached 

 the age of several thousand years, it is surprising that so many of 

 our shade trees should die so young. The age of a dragon tree 

 (Dracaena Draco) on one of the Canary Islands is said to be over 

 6,000 years; that of a Bald Cypress (Taxodium mucronatum) in 

 Mexico is believed to be over 4,000 years; and that of an English 

 Oak (Quercus pediwculata) in Europe and a ''big tree" (Sequoia 

 gigantea) in California is known to be over 2,000 years. Many 

 trees also have attained an enormous size, both in height and diam- 

 eter. The Eucalyptus in Australia is known to reach a height of 

 470 feet and the "Big Tree," the Redwood, and the Douglas Fir of 

 California often grow to a height of 300 feet. The Sycamore and 

 the Tulip Tree in the eastern states sometimes reach a height of 

 150 feet. The tree of largest diameter is found at the base of 

 Mt. Etna in Sicily. It is a species of Chestnut (Castanea vcsca) 

 and its trunk is over 60 feet in diameter. Some people claim that 

 this remarkable tree is the result of the union of several individuals. 

 The Oriental Sycamore comes next with a diameter of about 40 

 feet. 



These remarkable measurements are attained by trees growing 

 under favorable conditions. The most of our shade trees are not 

 growing under conditions most favorable to their development. It 

 is easy to find something wrong with the environment of almost 

 every tree, and this accounts for the failure or weakening of so 



