8 OKCHAKD GEEEN-MANUEE CEOPS IN CALIFOENIA. 



THE ORCHARD DISTRICTS OF CALIFORNIA. 



The orchard districts of Cahfornia so far as green-manure crops 

 are concerned at once divide themselves into the citrus and the 

 deciduous fruit districts. These are again readily divided into the 

 northern and southern citrus districts and the irrigated and nonirri- 

 gated deciduous sections. 



The two citrus districts have a definite geographical distinction, 

 while with the deciduous orchards water is the differentiating factor, 

 without reference to any geographical distinction. The citrus dis- 

 tricts are quite definite in area. The southern district is confined to 

 what is known as southern California proper and includes the territory 

 south of the Sierra Madre Mountains and north along the coast to 

 Santa Barbara. The northern district includes a narrow strip on the 

 east side of the San Joaquin VaUey from some distance south of 

 Porterville to Lemoncove, Tulare County, on the north; a similar 

 but smaller area in Fresno County; a small area in the Sacramento 

 Valley, centering about Oroville and Palermo; and various small 

 areas in other parts of the valleys and foothills. 



Conditions with regard to water, soil, climatic or seasonal varia- 

 tions, etc., are quite different in these various sections, and the plant 

 best suited to a certain area must be carefully considered in deter- 

 mining the probability of success with a green-manure crop. Prac- 

 tices satisfactory in one locality may be unsuited to another, and the 

 crop best adapted to one section may not be adapted to another. 



SOUTHERN CITRUS SECTION. 



The seasonal conditions of the southern citrus section are such as 

 to maiie this the most favorable part of the State for growing green- 

 manure crops. The locahty and climatic conditions are such that 

 these crops are practically never injured by frosts, and the mild 

 winters favor vegetative growth at that time of the year. 



In contrast with the deciduous sections, where there is usually a 

 heavy rainfall, here the rainfall is usually light. However, as irriga- 

 tion is given throughout the dry season the conditions are favorable 

 to the sowing of a green-manure crop early in the fall, thus giving 

 sufficient time for considerable growth before the cold weather of 

 winter. 



The soils vary considerably in composition and mechanical texture, 

 but as a general rule are of such a nature as to permit working at 

 almost any time during the winter, except after heavy rains, thus 

 favoring the turning under of a green-manure crop. While some 

 soils in this section are a rich loam and contain considerable organic 

 matter, as a rule they are quite deficient in this respect. That green 

 manures need to be more extensively used is evident. 



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