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UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. 



should not be submerged, but they should be wetted sufficiently to 

 prevent any danger of the drying out of the scions. This is accom- 

 plished by lateral seepage, if the water is run slowly along the hollows 

 between the ridges. A cultivator should be run between the rows 

 as soon as possible after the irrigation, but the ridges should not 

 be disturbed, if it is possible to avoid it, until the scions start. 



If the soil has a tendency to form a crust, however, it will be 

 necessary to break this crust after any rain that may occur at this 

 time. This is one of the most fruitful causes of failure. If the crust 

 is not broken the buds will have difficulty in pushing their way 

 through and the hard soil will dry down rapidly and many scions 

 be killed. The breaking of the crust must be done with great care, 



;* - : - * 



f 



FIG. 21. Irrigating the nursery. 



or the scions will be disturbed and make poor unions. If 2 inches 

 of soil have been placed over the scions a careful man can go over 

 the ridges with a short-toothed rake without injuring any grafts. 

 This should be done as soon as the soil is dry enough not to form 

 clods and before a crust has formed. It is better in this way to 

 prevent the formation of a crust than to break it up after it has 

 formed. This requires very prompt and rapid action, for in some 

 soils a crust forms in less than twenty-four hours after a rain. 



Until about the first or middle of July there is nothing to do to 

 the nursery but to keep the weeds down, and to see that the scions 

 do not become dry before they are supplied with water by the new 

 roots. 



The shoots from the scions should begin to appear above the ground 

 in one to two weeks after planting. These shoots are at first yellowish 



