Fox and Ludwig (1937), in their discussion of methods for the rearing of scarabaeid larvae, stated that the medium used in the rearing boxes may be varied in nature and composition, the main considerations being its capacity to hold moisture and supply food. For this purpose, the use of a vegetable mold, sifted plant detritus, was advocated because it has a high water-holding capacity, losing moisture more slowly than mineral soils and becoming wet less readily when water is added. They stated further that vegetable mold is readily consumed by scarabaeid larvae, Japanese beetles having been reared from egg to adult in this medium alone, although development is more rapid if other food, such as grains of wheat, is added. With this species they report that the best results were obtained when several grains of wheat were added to the plant mold at intervals of about a week during the growing period, the larvae feeding on the grain itself and on the growing rootlets as well as on the mold.
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