Trees for Todui' Witt Cttij 



must be made between untried native trees and those tested in a city 

 or town under different soil or climatic conditions, it is better to give 

 the native trees the first trial. Many promising native trees have not 

 been planted on a sufficiently large scale or under sufficiently varied 

 conditions to demonstrate their real value for street planting over 

 any considerable area. Many of the trees mentioned in this bulletin 

 may prove valuable far beyond the areas for which they are sug- 

 gested. The bur oak, the swamp white oak, the scarlet oak, the 

 chestnut oak, the white oak, the sour gum, and others may be found 

 on further trial to be as valuable as those already demonstrated to be 

 valuable over largo 

 areas. Those men- 

 tioned have all been 

 tested in a small way. 

 In many parts of 

 the country trees with 

 conspicuous flowers 

 and those with edible 

 fruits or nuts, and 

 even horse-chestnuts, 

 although the nuts are 

 not edible, are badly 

 mutilated by the pub- 

 lic. Every effort 

 should be made to cre- 

 ate a sentiment that 

 will protect these at- 

 tractive additions to 

 street adornment, but 

 where the sentiment 

 does not exist it is bet- 

 ter to avoid the plant- 

 ing of SUch trees ex- FIG. I. Narrow upright trees (Lombardy poplars) on a 



cept in a limited way. 



narrow street. Washington, D. C. ; midsummer. 



Some cities have ordinances against the planting of certain trees 

 because their roots sometimes obstruct sewers. Among these trees 

 are the Eucalyptus and some of the poplars. The silver maple is also 

 bad in this respect. The roots of any tree are liable to find their way 

 into a defective sew r er, but the trees mentioned are especially notice- 

 able because of their vigorous root growth. It may be questioned 

 whether a tree should be condemned for this growth, as it may be 

 better to have a defective sewer thus revealed than to continue a 

 menace to public health. 



The poplars and the silver maple are also objectionable because 

 their shallow roots often interfere with pavements, especially poorly 



