58 ARBOR DAY ITS HISTORY AND OBSERVANCE. 



MEDIUM-SIZED *TREES. 



Red maple (Acer rubrum}. 22. 

 Shingle oak (Quercus imbricaria), 21. 

 Willow oak (Quercus phellos), 21. 

 Slippery elm ( Ulmusfulva), 21. 



Horse chestnut (^Esculus Mppocastanum}, 



16. 



Japanese sophora (Sophora japonica), 16. 

 Hardy catalpa (Catalpa spewosa), 16. 



Norway maple (Acer platanoides], 20. \ Ginkgo or maiden hair tree (Ginkgo 



Box elder (Negundo aceroides), 20. biloba}, 16. 



European elm ( Ulmus campestris), 19. 

 Scotch elm ( Ulmus montaiia), 19. 

 Hackberry (Celtis occidentalis), 19. 

 Silver-leaved maple ( Acer dasy car pum), 17. 

 Tree of Heaven (Ailanthusglandulostis), 16. 



Honey locust (Gleditsia triacanthos), 15. 

 Cottonwood (Populu.s moirilifera), 15. 

 Balm of Gilead (Populus balsami/era var. 



candicans}, 15. 

 Black locust (Bobinia pseudacacia) , 14. 



SMALL-SIZED TREES. 



English maple (Acer campestre), 21. 

 Round-top locust (Bobinia pseudacacia- 



form), 18. 

 Red horse-chestnut (^Esculus rubictmda), 



17. 

 Laurel-leaved willow (Salix pentandra), 



17. 



Bay willow (Salix laurifolia), 17. 

 Green ash (Fraxinus viridis), 16. 

 European mountain ash (Sorbus aucupa- 



ria), 15. 

 American mountain ash (Pyrus ameri- 



cana\ 15. 

 Yellow wood (Cladastris tinctoria), 15. 



The rating of trees in this list does not differ essentially from the 

 average rating of the lists already referred to. Such lists can not be 

 taken as authoritative or decisive, but only as helps. Persons of 

 equally good judgment will differ in their estimate of particular trees, 

 and time and trial will be needed in order to reach a final decision as 

 to the trees best adapted for use in any given place. 



It hardly needs to be said that it is only on broad streets or where 

 buildings are set well back from the street that such widespreading 

 trees as some of the oaks are desirable for planting; but the oaks are 

 among our best trees where there is room for them, and they should be 

 planted on our streets, much more than they have been. For ordinary 

 streets, and especially for those which are narrow, such trees should be 

 chosen as do not grow to large size or such as are spiry topped. Of the 

 latter a new comer among us may be favorably mentioned, the ginkgo. 

 This is one of the few trees which it seems desirable to cultivate in addi- 

 tion to the large number of valuable native trees which we have. But 

 the peculiarity of its form and of its leaves, which mark a blending of 

 the broad-leafed and the needle-shaped leaves, and its wonderful golden 

 coloring in autumn, make it very attractive, and it is well adapted for 

 planting on narrow streets as well as singly in open, lawn-like spaces. 

 Whoever has seen the avenue leading up to the main building of the 

 Department of Agriculture, which is bordered with the ginkgo, must 

 feel that it is one of the most desirable trees for similar use. What 

 degree of cold this tree will endure remains to be seen, but it is growing 

 well as far north as Boston. 



A good word should be said also for the ailanthus. It was formerly 

 a favorite tree, but has been discarded on account of its unpleasant 

 odor in its flowering season. This, however, may be avoided by planting 



