322 CALIFORNIA VEGETABLES. 



must be made for even distribution of the water. To allow 

 low places to fill up with water is injurious and to allow 

 the water to come in contact with the plant stems is also 

 dangerous. A good, thorough, and uniform wetting of the 

 soil is often enough to finish the crop and it is seldom de- 

 sirable to irrigate after the bloom appears. Thorough sur- 

 face cultivation should quickly follow the irrigation, for 

 the reasons stated in the chapter on that subject. 



Mulching. For the last 35 years the practice of grow- 

 ing potatoes on the interior plains by the help of a straw 

 mulch has been followed to some extent. It has recently 

 been proposed at the east as a new method, but it is really 

 quite old. The seed is plowed in with a shallow furrow 

 so as to cover about three or four inches, then cover the 

 whole surface with partly decayed straw from an old 

 stack or with coarse manure. The mulch will retain 

 moisture enough to mature a crop. There need be no plow- 

 ing, hoeing, nor weeding, and it is held by those who ad- 

 vocate the method, that the labor of putting on straw is 

 compensated for the saving of hoeing and weeding. It is 

 also a safe way to grow early potatoes in frosty places be- 

 cause the mulch protects the dormant buds at the base of 

 the stems and new foliage quickly grows if the old is 

 nipped by frost. 



Harvesting. Potato diggers or plows are used to some 

 extent in California, but the common method of gathering 

 is by means of a long-handled shovel which is dexterously 

 pushed beneath the plant so that all the tubers are thrown 

 out at one operation. The yield of potatoes varies from 

 five to nine tons per acre on good soil, properly cultivated. 



Storing. As the summer and fall climate of California 

 is almost rainless and the frosts seldom severe enough to 

 freeze a potato in a sack, the tubers are generally sacked 

 and piled in the field for weeks and months. This advan- 

 tage is turned by careless growers into a disadvantage, be- 

 cause the potatoes are often seriously injured by heat and 

 light and shriveled by dry, hot winds, or the moth places 

 her eggs upon them and wormy and worthless potatoes is 



