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 vineyards. Furthermore native species, feeding, 

 unnoticed perhaps, upon wild growths have found, in certain in- 

 stances, 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, lady birds, etc., that are 

 valuable in this regard. Other factors also, such as untoward weath- 

 er-conditions at the time of hatching, bacterial and fungous diseases 

 of insects, etc., assist the horticulturist in his warfare against inju- 

 rious insects. It is also a fact that California conditions have de- 

 manded and favored the development of ways and means for the 

 suppression of orchard and vineyard pests, and methods and ap- 

 pliances have been invented which have demonstrated notable effi- 

 ciency 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 ; of the State Board of 



*I am indebted to Mr. W. T. Clarke, assistant professor of Horticulture of the 

 University of California, Berkeley, for careful revision and extension of this chapter. 



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