Effect of oil spray on California red scale at various stages of development

Ebeling, W

Effect of oil spray on California red scale at various stages of development

Author

Walter Ebeling

Author Affiliations

Walter Ebeling was Junior Entomologist in the Citrus Experiment Station.

Publication Information

Hilgardia 10(4):95-125. DOI:10.3733/hilg.v10n04p095. April 1936.

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Abstract

Abstract does not appear. First page follows.

Introduction

During several years of field investigation with oil sprays used against the California red scale, Aonidiella aurantii (Mask.), the writer has observed that often some insects may not have received a sufficient amount of oil to cause sudden death and that they may live for two or three weeks after other individuals have been killed. Where the lethal action is thus prolonged, the typical signs of death, such as dryness or discoloration of the body fluids, may not be definitely discernible until six weeks or more after the spray treatment. In many cases examinations of infested citrus groves a month after treatment with oil spray have revealed an unsatisfactory degree of control of the red scale; at the end of six weeks, however, the mortality of the insects was very much higher.

The work of (deOng, Knight, and Chamberlin (1927), p. 372) indicated that the lethal effect of highly refined oil sprays is the result of suffocation of the insect, but (Smith (1932)) has observed that often the oil does not reach the tracheae, and in that case death may be caused by a “prolonged impairment of physiological processes such as might be induced by the presence of oil in the scale covering or in contact with the derm of the insect’s body.” In cases in which the lethal effect is retarded because of incomplete suffocation, the appearance of the insect indicates that it has some oil in its body. Its scale covering is oily, and a certain amount of dust has adhered to the oil film.

Literature Cited

deOng E. R., Knight H., Chamberlin J. C. A preliminary study of petroleum oil as an insecticide for citrus trees. Hilgardia. 1927. 2(9):351-384. DOI: 10.3733/hilg.v02n09p351 [CrossRef]

Ebeling W. Method for determination of the efficiency of sprays and HCN gas used in the control of the red scale. California State Dept. Agr. Mo. Bul. 1931. 20:669-672.

Ebeling W. Experiments with oil sprays used in the control of the California red scale Chrysomphalus aurantii (Mask) (Homoptera: Coccidae) on lemons. Jour. Econ. Ent. 1932. 25:1007-1012.

Haas A. R. C. Relation between the chemical composition of citrus scale insects and their resistance to hydrocyanic acid fumigation. Jour. Agr. Research. 1934. 49:477-492.

Kono M. Chemical studies on coccids produced in Japan. Jour. Agr. Chem. Soc. Japan. 1932-35. 8:1150-60. 9: 458-66, 467-74, 775-82, 1276-83; 10: 360-67, 1228-35; 11: 21-28, 647-58. Abstracted in: Chem. Abstr. 27: 1409, 4312; 28: 2418, 5538; 29: 1168, 3045, 6958.

Metcalf C. L., Hockenyos G. S. The nature and formation of scale insect shells. Illinois State Acad. Sci. Trans. 1930. 22:166-184.

Nel R. G. A comparison of Aonidiella aurantii and Aonidiella citrina including a study of the internal anatomy of the latter. Hilgardia. 1933. 7(11):417-466. DOI: 10.3733/hilg.v07n11p417 [CrossRef]

Smith R. H. Experiments with toxic substances in highly refined spray oils. Jour. Econ. Ent. 1932. 5:988-990.

Smith R. H. The tank-mixture method of using oil spray. California Agr. Exp. Sta. Bul. 1933. 527:1-86.

Woglum R. S. The use of oil spray on citrus trees [Abstract.]. Jour. Econ. Ent. 1926. 19:732-733.

Woglum R. S., La Follette J. R. The double treatment for scale pasts in California citrus orchards. Jour. Econ. Ent. 1934. 27:978-980.

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