. Circular. Insect pests; Insect pests. area of about 6 acres, mostly in alfalfa. He stated that although the live grasshoppers were vet ver}' thick, many appeared weak and in a dying condition. ^Vhen received the material was simply a mass of decaying bodies of grasshoppers and among them were both maggots and j^upa? of Sareophaga georgina. These flies deposit minute, elongated, ivory-white eggs on the surface of the bodies of the grasshoppers. The young maggots hatching from these make their w^ay directly into the bod}- of their host, and as they grow and develoj) there they feed upon the li
. Circular. Insect pests; Insect pests. area of about 6 acres, mostly in alfalfa. He stated that although the live grasshoppers were vet ver}' thick, many appeared weak and in a dying condition. ^Vhen received the material was simply a mass of decaying bodies of grasshoppers and among them were both maggots and j^upa? of Sareophaga georgina. These flies deposit minute, elongated, ivory-white eggs on the surface of the bodies of the grasshoppers. The young maggots hatching from these make their w^ay directly into the bod}- of their host, and as they grow and develoj) there they feed upon the living insect. "^^Hien full gi'own the maggots go into the ground and within a brown case transform to flies. "^^liile all of these natural enemies do much to hold the pests in check, there are two or three vegetable parasites that also kill otf myriads of them, the dead bodies of the grasshoppers destroyed thereby often being conspicuous objects as they cling to the weeds and grass where death overtook them (see fig. 6). One of these fun- gous i^arasites is the same as that attacking the chinch bug, and is known to science as Bporotrichum glohvli- ferum. A group of grasshoppers that have been killed by this fun- gus is shown in figure 7. While it will be seen that there is no lack of natural enemies of these grasshoppers, and Avhile all of them are of benefit to the farmer, they do not and never will afford absolute protection from the rav- ages of these pests in the alfalfa fields. The reason for this is plain. By growing a single plant over large areas the farmer produces an unnatural condition and offers unnatural advantages for the devel- opment of the enemies of this plant, the grasshoppers. It is really the number of plants that invites insect attack. So, also, it is the great number of grasshoppers congregated together in masses that invites attack from natural enemies, and it is only when this condi- tion is present that these natural enemies become sufficientl
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectinsectp, bookyear1904
