328 TRANSACTIONS OF THE 



proof of conditions of temperature similar to those of the valley. Wherever, 

 he declared, the oaks, digger pine, buckeye, and chemisal, or any of them, 

 constitute the preponderant arboreal vegetation, plants that can be success- 

 fully grown in the valley, can be successfully grown upon the hills. The 

 experience of practical horticulturists has amply corroborated these con- 

 clusions by Mr. Redding, whose keenness of observation and powers of 

 generalization were alike remarkable. To this general rule, however, some 

 exceptions may be found, as in the case of the orange, with which the dif- 

 ference of a dozen or half dozen degrees of minimum temperature may be 

 a matter of life and death. There are places in the foothills, of an eleva- 

 tion of 2,000 feet or more, whose average temperature corresponds closely 

 with that of the Sacramento Valley, but which are, however, liable to be 

 occasionally visited by more severe cold than is ever experienced in the 

 valley. 



For the purpose of illustrating the similarity of the climate of the foot- 

 hills and the valley in respect to temperature, the "Appeal" has made a 

 comparison of the records of Auburn and Marysville for the month of Jan- 

 uary just passed. The data for the comparison are found in the local 

 weather table published by the " Republican," at Auburn, and that of the 

 "Appeal" for this place. Both records show the readings of self-register- 

 ing instruments, and the results are as follows: 



Auburn. Marysville. 



: , 



Highest temperature 65.0 67.0 



Lowest temperature 13.0 18.0 



Average of thirty-one maximum readings 50.5 49.7 



Average of thirty-one minimum readings 33.5 35.3 



Average temperature for month 42.0 42.5 



The altitude of Auburn, according to the Smithsonian tables, is 1,176 

 feet, and of Marysville 80 feet. Yet, despite this difference of about 1,100 

 feet in elevation, the comparison above made indicates that the conditions 

 of temperature are substantially uniform at the two places, Marysville hav- 

 ing but little advantage over -the foothill town. 



It might be supposed, from the dense growth of native trees and bushes 

 found in most portions of the foothills, compared with the relatively tree- 

 less condition of the valleys, that there is a radical difference in the climate 

 of the two regions. But the difference of vegetation is probably due mainly 

 to the dissimilarity of soil and drainage. The red soil of the foothills is 

 always more or less gravelly, and, from both its chemical and mechanical 

 composition, is warmer and more friable than the comparatively heavy soils 

 of the valley. So far as the abundant tree growth in the foothills may be 

 due to difference of climate, as compared with the valley, the chief factor 

 must be greater rainfall. The dense native growth of trees and bushes in 

 the foothills is nature's testimony to the adaptability of the region to the 

 culture of fruit trees and vines. And who can doubt that where trees and 

 bushes spring up and thrive from seed sown by the winds upon the unfilled 

 earth, with no other aid than the rain and sunshine, the same soil, under 

 deep tillage and thorough cultivation, will give vigorous growth and rapid 

 maturity to fruit trees and the vine, without irrigation? There is probably 

 no tree or bush, native to the hills, needing less moisture than the olive tree 

 and grapevine, and it is entirely safe to undertake the culture of these two 

 upon any land in the hills that has sustained the digger pine, any descrip- 

 tion of oak, or the familiar "chaparral." Even the luscious peach and 



