. Citrus fruits; an account of the citrus fruit industry, with special reference to California requirements and practices and similar conditions . months for the female. After theproduction of eggs, the female soon dies. During the ordinary season, there are from three to fourgenerations. The young seem to be more able to adapt them-selves to unfavorable feeding conditions than either the redor the black scales, and the percentage which become estab-lished is much greater. Several species of ladybird beetles prey upon the purple 41G Cifnift m «;?? Fig. 142. — Tho purple scale. (Enlarge
. Citrus fruits; an account of the citrus fruit industry, with special reference to California requirements and practices and similar conditions . months for the female. After theproduction of eggs, the female soon dies. During the ordinary season, there are from three to fourgenerations. The young seem to be more able to adapt them-selves to unfavorable feeding conditions than either the redor the black scales, and the percentage which become estab-lished is much greater. Several species of ladybird beetles prey upon the purple 41G Cifnift m «;?? Fig. 142. — Tho purple scale. (Enlarged.) scale, but only one internal parasite has so far been parasite is not very widely distributed and is only Citrus Insects and their Control 417 partially effective wherever it is found. In orchards wherethe red, black, and purple scales occur together, fumigation ismainly directed against the purple; if it is killed, the dosageis usually fatal to the other two. Cottony Cushion Scale (Iccrya purchasi) The account of the introduction, spread, and final controlof the cottony cushion scale forms one of the most interesting. chapters in the history of California horticulture. Havingbeen introduced from Australia in 1868 (see Chapter I)it spread so rapidly tluring the next twenty years that itsravages proved a very serious menace to the citrus industryof the southern part of the state. The Australian ladybirdbeetle which was introduced into California from Australiain 1889 for the purpose of controlling this scale was so success-ful, to all appearances, that except for occasional outbreaksit ceased to be considered as a serious citrus pest, and fumi-gation or other measures of repression are no longer 418 Citrus Fruits The mature scale is very easily distinguished from otherscales. When mature, they are about one-fourth of an inchlong and consist of the red or yellowish body and a largefluted cottony white mass which serves as the five to e
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectcitrusfruits, bookyea
