. Agriculture [microform]. Agriculture; Agriculture. §4 AGRICULTURE, ) â : Fig. 39.âCaterpillar covered with parasites. In tlie case of house plants, garden plants and orchard trees we can wash and spray with solutions that destroy the lice, but with lice that injure the grain such means are not yet practi- cable. Why then do not the lice nuilti[)ly so as to eat u[) everything in the fields? Simply because there are other insects that keep them in check. There are some tiny flies that atiack the lice and lay their eggs right in the bodies of the lice. These parasites soon kill the lice. Other
. Agriculture [microform]. Agriculture; Agriculture. §4 AGRICULTURE, ) â : Fig. 39.âCaterpillar covered with parasites. In tlie case of house plants, garden plants and orchard trees we can wash and spray with solutions that destroy the lice, but with lice that injure the grain such means are not yet practi- cable. Why then do not the lice nuilti[)ly so as to eat u[) everything in the fields? Simply because there are other insects that keep them in check. There are some tiny flies that atiack the lice and lay their eggs right in the bodies of the lice. These parasites soon kill the lice. Other insects are destroyed in the same way, such as cater- pillars and grasshoppers. If we carefully examine the leaves of trees or other plants infested with lice we may find some of the beautiful little lady-beetles and their larva3 feeding upon the lice. Another enemy of lice is the aphis-lion, the larva of a lace-wing fly. FliesâIf you examine a common house-fly or a mosijuito, you observe that it has only two wings. Here then we have another order, that of the "two winged" flies, known as diptera. The Hessian fly, the wheat midge, the many flies of root plants, moscjuitoes, fleas, and many of the flies that annoy stockâall have two wings only and belong to this order. The Hessian fly a[)j)ears in spring as a small winged insect with long legs. 'I'he female lays about twenty eggs in the fold or crease of the leaf of the young wheat plant. After a few days the larva) hatch and gi't down between the stem and k-af-sluath. I Icre they feed on the plant and wtakeii it so that the heavy head soon altii" loppKs osi-r antl the grain is iKslroNcd. The eggs may bi- laid either in the spring or in the early fall. When the latter is the. FiR. 40 â'I'lio Hessian lly, a two-winged insect. i I:. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may
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Keywords: ., bookauth, bookcentury1800, bookdecade1890, booksubjectagriculture
