The tortoise wax scale, Ceroplastes japonicus Green, is important injurious insect to garden trees.
This paper present results of a some ecological study, with especialy host plant made during 1965-1968 on the tortoise wax scale, Ceroplastes japonicus Green in Setagaya, Tokyo, Japan.
The results obtained are as follows:
The natural host plants of the tortoise wax scale amounted to total of over 40 families 118 species (including varieties) were reported.
In the list, Fam. Rosaceae takes rank as the fi rst in number of species (including varieties), Moraceae as the second, and Fagaceae as the third, followed by Rutaceae, Theaceae, and Ericaceae.
This insect is one generation in a year, and the winter is passed as a fertilized female.
The female deposite her eggs beneath the body, and wich is filled by the mass of eggs. The number of eggs laid by a single female is variable, our record ranging from 23 to 1917.
