ARBORICULTURE 



ARBORICULTURE 



379 



characteristic of arid regions take their place. The 

 reverse of this is true, as one goes north, where many 

 trees of the temperate humid regions also thrive in 

 this state, particularly in the relatively humid climate 

 of the coast, and are offered by our nurserymen. 



I. The Species Heretofore Most Extensively 



Planted in California. 



The following trees are perhaps the coimnonest 

 species found in the plantings: 



1. Eucalyptus ;;lobuliis. 15. Araucaria Bidwillli. 



2. Cupres.sus raaerocarpa. 16. Araucaria excelsa. 



3. Pinus radiata. 17. Populus deltoides var. 



4. Robinia Pseudacacia. carolinensis. 



5. Acacia melanoxylon. 18. Juglans californica and 



6. Schinus Molle. species. 



7. Acacia decurrena var. 19. Salix babylonica. 



dealbata. 20. Acer saccharinum. 



8. Acacia decurrena var. 21. Eucalyptus robusta. 



mollis. 22. Eucalyptus virainalia. 



9. Melia Azedarach var. 23. Eucalyptus rostrata 



umbraculiformis. (Fig. 360). 



10. Phcenix canariensis 24. Acer macrophyllum. 



(Fig. 358). 25. Pittosporum species. 



11. Magnolia grandiflora. 26. Cedrus Deodara and 



12. Ulmus racemosa and species. 



species. 27. Betula alba. 



13. Cordyline australia (Fig. 28. Grevillea robusta. 



359) and species. 29. Washingtonia filifera. 



14. Acer Negundo, and var. 30, Cinnamomum Camphora 



californica. 



II. Trees Being Most Extensively Planted in 



California at the Present Time. 



The following hst, arranged in sequence according 

 to the actual number of sales made during the sea- 

 son of 1911-12, is compiled from data furnished by 

 W. B. Clarke, of the California Nursery Company, 

 at Niles. The percentages refer only to the twelve 

 species here enumerated, and not to the total number 

 of trees sold by the nursery, which has a large and 

 varied assortment of species, many of which aie more 

 suitable and more effective than those for which there 

 is, at present, the greatest demand. 



Per cent. 



Eucalyptus globulus 40.8 



Cupressus macroearpa 12.0 



Platanus orientaiis 11.4 



Eucalyptus rostrata 10.2 



Populus nigra italics 6.2 



Pinus radiata i^.0 



Acacia decurrens dealbata 3.5 



Acacia melanoxylon 3.0 



Populus deltoides var. carolinensis 2.2 



Robinia Pseudacacia var. Decaisneana 2.0 



Acer saccharinum 2.0 



Schinus Molle 1.7 



III. Selections for Special Purposes. 



The following lists are from species now offered in 

 the California trade and are intended to be suggestive 

 only, and not by any means complete. New species and 

 varieties are constantly being added to the nursery 

 stocks, some of which will be found particularly well 

 adapted to certain conditions of climate and soU, and 

 will doubtless replace others now in use. 



1. For subtropical effect. 



That there is in California strong appreciation of 

 subtropical effects in gardening is shown by the great 

 demand for dracenas and such large-leaved plants as 

 palms, magnolias, bananas and rubber trees. That the 

 effect produced by the planting of such trees so often 

 fails to be satisfatoiy^ is largely due to one or both of 

 two causes, — either unsuitable location of the speci- 

 mens, or choice and association of unsuitable species. 

 To prevent a repetition of the first-named error, the 

 piospective tree planter is recommended to consult the 

 article on Landscape Gardening; and to avoid the 

 second, a selection from the following hst is suggested, 

 with the addition of such large-leaved herbaceous 

 plants as cannas, colocasia, cynaras, funkias, Guyinera 

 scabra, pampas grass, veratrunos, agaves, yuccas, aloes, 



Woodwardia radicans and Rodgersia podophylla, to- 

 gether with such shiubby plants as bamboos, giant reed, 

 the choicer varieties of castor-bean, Senecio grandi- 

 folius, Polygonum sachalinense and P. Sieboldii. 



A. Sviall trees or tall shrubs. 



Acanthopanax ricinifolium. 



Aralia chinensis. 



Aralia chinensis var. mand- 



schurica. 

 Aralia spinosa. 

 Arundinaria falcata. 

 Chamterops hurailis. 

 Dicksonia antarctica. 

 Eriobotrya japonica. 



Erythea armata. 

 Musa Ensete. 

 Prunus Laurocerasus. 

 Ricinus cambodgensig. 

 Ricinus macrophyllus. 

 Ricinus sanguineus. 

 Ricinus zanzibarensis, 

 Tetrapanax papyrifera. 



Catalpa bignonioides. 

 Catalpa ovata. 

 Catalpa speciosa. 

 Cordyline australia. 

 Cordyline Banksii. 

 Cordyline indivisa. 

 Cordyline stricta. 

 Corynocarpus. 

 Er>*thea edulis. 

 Eucalyptus calophylla. 

 Eucalyptus ficifolia. 

 Ficus Carica. 

 Ficus macrophylla. 

 Gymnocladus canadensis. 

 JubEea spectabilis. 



AA. Larger trees. 



Livistonia australia. 



Magnolia grandiflora, 



Paulownia tomentosa. 



Phcenix canariensis. 



Phcenix dactylifera. 



Phcenix reclinata. 



Phcenix Rcebelenii (P. humilis 



var.) 

 Phcenix sylvestris. 

 Phytolacca dioica. 

 Trachycarpus exeelsus. 

 Tris'.ania conferta. 

 Washingtonia filifera. 

 Washingtonia robusta. 



Eucalyptus globulus can also be used effectively if cut 

 down periodically when the falcate leaves begin to ap- 

 pear; it will continue to shoot up vigorously from the 

 same root for several years. E. robusta is useful for 

 screen purposes if cut do^Ti before it becomes strag- 

 gUng. This can also be said for E. polyanlhemos, E. rudiSj 

 E. Risdouii, and many others. E. polyanthemos is cer- 

 tainly more beautiful than E. globulus and would not 

 need to be cut down so frequently. 



2. Trees with ornamental flowers (for California) 



In making the following grouping, arranged accord- 

 ing to relative hardiness, it has been impossible to give 

 precise information as to the exact degree of frost- 

 tolerance of the several species, as only meager pub- 

 lished data on the subject are to be found. 



A. Susceptible to light frost. 

 The following would probably succumb to a temper- 

 ature of 28° F. : 



Eucalyptus calophylla. Jacaranda ovalifolia. 



Eucalyptus ficifolia. 



AA. Susceptible to heavy frost. 



The following are not likely to stand a temperature 

 of 20° F. Some of them may succumb at 25° F., particu- 

 larly when young. 



