68 STREET AND HIGHWAY PLANTING. 



with few exceptions, as the dust conditions are particularly trying to 

 them. 



2. If the water supply is slight (i. e. the natural supply after trees 

 are established), do not select species needing abundant soil moisture. 



3. If there is alkali, use trees which will tolerate such amounts as 

 may be present. 



4. Select trees which will harmonize with native vegetation. Do 

 not plant species characteristic of arid regions in the semi-humid parts 

 of the State and do not plant trees characteristic of humid regions in 

 the arid portions of the State. While all street work must be artificial 

 to a slight degree, there is a certain fitness of things which is essential. 



Trees causing considerable litter all the year. 



Albizzia lopantha. Magnolia grandiflora. 



Eucalyptus species. Melia azadarach. 



Eriobotrya japonica. Morus alba. 



Ficus macrophylla. Morus rubra. 



Grevillea robusta. Sterculia diversifolia. 

 Lagunaria patersonii. 



Trees causing litter from fruit. 



Albizzia lopantha. Olea europea. 



Castanea sp. Pistacia terebinthus. 



Eriobotrya japonica. Primus' ilicifolia. 



Eucalyptus. Prunus integrifolia. 



Ficus species. Robinia pseudacacia. 



Ginkgo biloba. Schinus molle. 



Grevillea robusta. Tilia europea. 



Melia azadarach. Ulmus species. 



Morus species. Umbellularia californica. 

 Conifers useful only on widest roads where wide parking space is available. 



Araucaria species. Cupressus guadelupensis. 



Cedrus atlantica. Cupressus macrocarpa. 



Cedrus deodara. Pinus species. 

 Cupressus arizonica. 



Trees especially short-lived in good form. 



Acacia Baileyana. Albizzia lopantha. 



Acacia pycnantha. Betula alba and its varieties. 



Acacia lopantha. Cupressus macrocarpa. 



Acer saccharinum and its Pinus radiata. 



varieties. Platanus occidentalis. 



Trees needing abundant soil moisture. 



Acer species. Magnolia grandiflora. 



Betula alba. Quercus suber. 



Ginkgo biloba. Sequoia sempervirens. 



Liquidambar styraciflua. Taxodium species. 



Liriodendron tulipifera. Umbellularia californica. 



