IN CALIFORNIA 53 



cept under similar conditions in forest reserves. 

 The hardiest species that grows to the dignity of a 

 tree is E. Gunnii, but its growth is too slow for pop- 

 ular use. E. coccifera, cordata, urnigera, saligna, 

 resinif era, and viminalis grow in Cornwall, England, 

 but only one, viminalis, thrives well in the colder 

 parts of California. 



Under the stress of great heat other species thrive 

 equally as well as do those of the former list in lands 

 of heavy frosts and snow. At Thermal, California, 

 on our so-called Colorado Desert, twenty-five species 

 were tried out, about one hundred plants of each 

 being used for the test. Of these five species success- 

 fully withstood the heat with a continuation of vig- 

 orous annual growth. These were: E. leucoxylon, 

 the Victoria iron bark; E. polyanthema, the red box; 

 E. rostrata, the red gum; E. rudis, and E. viminalis, 

 the manna gum. Of these five the last-named grew 

 more rapidly and straighter than the others, and 

 during the first year many attained a height of 

 fifteen feet. For extremes of both heat and cold it 

 is the best species of all, a truly wonderful tree in 

 its climatic adaptation. 



TREES FOR ARID REGIONS 



There are many trees quite common, which will 

 endure the heat of these sections, but not all will 

 withstand the cold, and in the appended list care 

 must be taken that frosts are not too severe for some 

 of those named. 



Among the best trees are : Beef -wood or she-oak, 

 casuarina; pepper, Schinus molle; Texas umbrella, 

 melia; black locust, Robinia pseudacacia; honey lo- 

 cust, Gleditschia triacanthos ; several willows ; box 

 elder, Acer negundo; cotton woods, several species; 

 at least five eucalypts rostrata, rudis, tereticornis, 



