4 INTRODUCTION. 
but has to do more especially with the genus as it behaves in North 
America. “Only those species that have fruited and by this means 
have been identified are treated. This treatise is based mainly upon 
ten years’ observation and study of the genus in California and Ari- 
zona and three years of experimental work in the latter region. 
Besides the data obtained as a result of this personal work, very 
much of value concerning the genus has been learned through cor- 
respondence with students and growers of Eucalypts in the various 
regions where they grow naturally or have been introduced. In this 
connection I wish to acknowledge especial indebtedness to the follow- 
ing persons for valuable assistance rendered: Hon. Abbot Kinney, 
Los Angeles; Hon. Ellwood Cooper, Santa Barbara; Mr. J. H. Maiden, 
F. L. S., government botanist, Sydney, Australia; Mr. F. Manson 
Bailey, F. L. S., colonial botanist, Brisbane, Australia; Prof. L. 
Trabut, Alger-Mustapha, Algiers; E. R. Holmes, Paris; Nathan W. 
Blanchard, Santa Paula, Cal.; and Col. G. H. Norton and A. K. 
Sanders, Eustis, Fla. 
The purpose of this bulletin is to give information concerning the 
characteristics of the Eucalypts, their climatic requirements, and their 
uses; to give directions and suggestions as to their propagation and 
culture; and to furnish a means of identifying seedlings and mature 
trees, so that as the Eucalypts growing throughout the Southwest 
become identified, such trees may become sources of information con- 
cerning the species they represent, and sources of seed for propaga- 
tion. This Australian group of trees now serves very many useful 
purposes in the Southwest, and gives promise of great future useful- 
ness in the semiarid portions of our continent. It is believed that 
when the merits of these trees are fully understood, and information 
concerning their climatic requirements and their propagation is readily 
available, they will be planted more extensively and with increasing 
intelligence and discrimination. The covering of the now untillable, 
treeless portions of the semitropic section of America with such trees 
as Eucalypts, which will yield fuel, timber, and other useful products, 
and also furnish protection from the sun, from winds, and from floods, 
or otherwise ameliorate existing climatic conditions, is certainly an 
achievement greatly to be desired. 
The illustrations are from photographs made by the writer during 
the past six years. Photographs of most of the seedlings in pots were 
made at a nursery in South Pasadena, Cal., the proprietors of which 
were extensive American growers of Eucalypts. The remainder were 
taken at the experiment station farm near Phoenix, Ariz. Seedlings 4 
to 8 months old, as nearly typical of the respective species as possible, 
were selected for subjects. It is believed that these illustrations will 
prove useful to growers and purchasers in identifying seedlings of these 
