PART NINE: FRUIT PROTECTION 



CHAPTER XXXIX 

 CALIFORNIA METHODS WITH INJURIOUS INSECTS 



The California climate, which so favors tree and vine by a long, 

 mild, growing season also enables some insects to multiply much more 

 rapidly than they do in wintry climes ; some having several distinct 

 broods, others carrying on the work of reproduction and destruction of 

 plants nearly the year round. The difficulties of the problem of the 

 control of injurious insects are constantly being increased because 

 new pests, in spite of the most careful efforts to keep them outside 

 our boundaries, occasionally find their way into our orchards and vine- 

 yards. Furthermore native species, feeding, unnoticed perhaps, upon 

 wild growths have found, in certain instances, that cultivated plants 

 offer to them most satisfactory food and then suddenly become a 

 factor in the horticulturists' problem, 



Undoubtedly parasitic and predaceous insects preying upon the 

 injurious species found in the fruit plantations are of assistance, in 

 greater or lesser measure, in reducing the pests, and this service is 

 being promoted by the introduction of beneficial insects from other 

 parts of the world. There are many of our native species of insects, 

 also syrphus and ichneumon flies, ladybirds, etc., that are valuable in 

 this regard. Other factors also, such as untoward weather-conditions 

 at the time of hatching, bacterial and fungous diseases of insects, etc., 

 assist the horticulturist in his warfare against injurious insects. It is 

 also a fact that California conditions have demanded and favored the 

 development of ways and means for the suppression of orchard and 

 vineyard pests, and methods and appliances have been invented which 

 have demonstrated notable efficiency and value. 



While the literature upon the subject of insect pests in California 

 is quite extensive, much of it is beyond the reach of the general 

 reader. Nevertheless there are a number of publications which should 

 be secured and studied by every fruit grower. These are the bulletins 

 and reports of the Agricultural Experiment Station of the University 

 of California, at Berkeley (from which many of the following state- 

 ments are taken) ; of the State Board of Horticulture, at Sacramento; 

 and of the Bureau of Entomology of the United States Department 

 of Agriculture, at Washington. A most useful addition to the horti- 

 culturist's library will be found in Kellogg's "American Insects," pub- 

 lished by Henry Holt and Company, New York. This excellent work 

 of Professor Vernon Kellogg, of Stanford University, is particularly 

 valuable because of its California observations and point of view. The 

 latest and at the same time the most specific and practically valuable 

 review of fruit pests and their control is "Injurious and Beneficial 

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