REST OF TREES NOT DUE TO FROSTS 17 



observation and experience, but often varieties of these fruits must 

 be chosen with reference to adaptation to local environment. For 

 this reason it is impossible to compile tables of varieties suited for 

 wide areas and yet it is true that some varieties have shown them- 

 selves hardy and satisfactory under all conditions. These facts will 

 be shown by the discussion which will be given to each of the 

 different fruits. 



REST AND ACTIVITY OF FRUIT TREES 



Indication has already been made of regions adapted to the 

 growth of early and of late fruits. There is, of course, difference 

 in time of rest and of returning activity in blooming. On the 

 mountains under wintry conditions the trees leaf out and bloom 

 late, following more or less the habit of Eastern trees. In the 

 foothills, the valleys, and the coast, there is less difference in time 

 of rest and of leaf and bloom. Even in regions where there may 

 be a month's difference in ripening of fruit, as, for example, in the' 

 Vacaville district, fifty miles inland, and in Berkeley, two miles from 

 the bay shore, trees bloom almost at the same date. The difference 

 in ripening is due to the higher temperature and fuller sunshine of 

 the interior situation, which have a forcing effect, while the low 

 temperature and dull skies of the summer on the coast retard 

 maturity. 



The rest of the tree, in all save the mountain district, is not 

 dependent upon the touch of frost. It comes rather from thirst than 

 from cold. The immense weight of fruit, the vigorous growth of 

 wood, and the exhaustion of moisture from the soil by the draught 

 of the roots to compass this growth, are the chief causes which 

 bring the sere and yellow leaf in California. It is not frost, for the 

 petunias may be blooming and the tomato vines still green in the 

 fields. But the time has come for a rest. The trees sleep ; but merely 

 as a nap at midday ; the early rains wake them soon. The roots 

 are active first, then the buds swell, and the blossoms burst forth 

 sometimes as early as January the almond first heralding the advent 

 of California's springtime. 



Sometimes this season of rest is too short for the good of the 

 tree or vine. The early rains, when followed by a spring-like tem- 

 perature, as sometimes happens, induce activity in the top as well 

 as the root, and the tree is not in condition to withstand cold 

 weather, which may follow. It is probable that such stimulated 

 activity, suddenly checked, is responsible for more ills to tree and 

 vine than are usually attributed to it. Both to insure hardiness and 

 fruitfulness it is important that a tree shall have summer moisture 

 enough to finish its late summer and early autumn growth-processes. 

 Reference to this 'important matter is made in the chapter on 

 irrigation. 



