. The cereals in America. Grain. THE CEREALS IN AMERICA. spikes when harvested, and are believed to survive in the straw for months without food or moisture. Preventive measures are (i) the burning of chaff and screenings as soon as the wheat is threshed, and (2) deep plowing of stubble field to bury the larvae and pupae. 155. The Wheat Plant-louse.—This insect appears on winter wheat in September, going through several generations in the early fall but doing little damage. If the spring is cool and moist, its natural enemies may fail to hold it in check and it may then cause considerable dama
. The cereals in America. Grain. THE CEREALS IN AMERICA. spikes when harvested, and are believed to survive in the straw for months without food or moisture. Preventive measures are (i) the burning of chaff and screenings as soon as the wheat is threshed, and (2) deep plowing of stubble field to bury the larvae and pupae. 155. The Wheat Plant-louse.—This insect appears on winter wheat in September, going through several generations in the early fall but doing little damage. If the spring is cool and moist, its natural enemies may fail to hold it in check and it may then cause considerable damage. Extensive damage has occurred only at rare intervals, as in 1861 and iSijg. l No effective remedy has yet been suggested. 156. Insects Injurious TO Stored Grain.—While upwards of forty differ- ent species of insects occur in granaries, f*lie following four species are the most injurious: 2 (i) The granary weevil (Calandra granaria L.) (2) The rice weevil (Calandra oryza L.) (3) The Angoumois grain moth (Sitot- roga cerealella Oliv.) (4) The wolf moth (Linca granella L.) The first two are beetles and the last two moths. The larvae of the first three live within the grains, as do the adults of both weevils. This adds very much to their injurious effects, to the ease with which they may be distributed, and the difficulty of eradication. All breed more rapidly in warm than in cold weather and consequently do their greatest damage in the southern sections of the country, where they cause enormous losses. The simplest and best remedy is the use of bisulphide of carbon at the rate of one pound to one ton of grain or in empty rooms for every 1,000 cubic feet. There are a number of insects injurious to flour. The Mediterranean flour moth (Ephestiakxielmiella Zell.) has recently become a most serious pest, requiring the adoption of extensive precautions in flouring mills to guard against its ravages. Beetle and larva of the granary weevil. (After Chittenden.) Adult and larva of t
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Keywords: ., bookauthorhuntthom, bookcentury1900, bookdecade1900, bookyear1904
