20 Advantage of Ample Feat. 
Lowest TEMPERATURE AT SEVERAL CALIFORNIA POINTS. 
6 6 é 
Bo a5 oo 
oN : oN : ON 
Coast and Coast Valleys. boy Interior Valleys. bee Foot-hills. bow 
ag as ag 
< < < 
Bure Kaerasatevessre ese 20 [Redding : eebeeerensiees 18 
Cape Mendocino.....| 28 Red Bluff....... sexfi 16 
Hydesville....... 24 Oroville......... san 20 at 
INA Pats cecnceticctosdend 20 Marysville...... v-| 20 16 
San Francisco... 28 Sacramento. 19 12 
San Jose..... 22 |Merced... 20 
GiltOyicseecas: 20 |Fresno........... | 18. 08 
San Miguel.............] 17 Tulare City... 14 22 
Los Angeles............| 28 Colton... 0... 22 ws 
San Diego... .. ..... B32 POWAY seevivers sveasuees 21 |Fall Brook... ........] 27 
These records will show anyone familiar with winter killing 
of the leading orchard fruits that such disasters are not to be 
feared in the chief fruit regions of California. Local tempera- 
ture is largely controlled by local conditions, as has been aiready 
pointed out, and in the districts named in the table there are 
special locations where the lowest temperature probably ditfered 
a few degrees from the figures given. 
NECESSITY OF ADEQUATE SUMMER HEAT. 
Passing beyond the freedom from winter killing, it may be 
remarked that the influence of certain degrees of heat upon the 
growth of the plant and the perfection of its fruit, has been the 
subject of much close observation. Boussingault conducted 
careful experiments, and showed that a temperature above a cer- 
tain minimum of heat is found necessary for gerniination, an- 
other for chemical modification, and a third for flowering, a 
fourth for the ripening of seeds, a fifth for the elaboration of the 
saccharine juices, and a sixth for the development of aroma or 
bouquet. 
Originally the mean annual temperature was alone ob- 
served, and the polar limits of plants, it was presumed, could be 
thereby determined. More recently it was taught that the mean 
temperature of seasons is of more importance than that of the 
year, and it is believed that to the relative distribution of heat 
over the seasons rather than to the absolute amount received 
during the year, we are to attribute the fitness or unfitness of a 
region for the growth of certain kinds of vegetation. 
It is held in Hurope that the mean heat of the cycle of 
vegetation of the vine must be at least 59° Fahr., and that of 
the summer from 65° to 66° Fahr. Jt is stated to be impossi- 
ble, for instance, to cultivate the vine upon the temperate table- 
