Economic entomology for the farmer and fruit-grower : and for use as a text-book in agricultural schools and colleges . the most serious enemies of wheat,actually inhibiting its cultivation in some localities. The adultis rather large for this family, smoky brown in color, and appearslate in the season, usually after the wheat is well above are laid on the young pjlants, and the larvae work their wayinto the stem at or near the surface, causing a slight gall or swell-ing and a deformity in plant growth. When winter sets in fullsize has been reached, and the flaxseed stage is entere
Economic entomology for the farmer and fruit-grower : and for use as a text-book in agricultural schools and colleges . the most serious enemies of wheat,actually inhibiting its cultivation in some localities. The adultis rather large for this family, smoky brown in color, and appearslate in the season, usually after the wheat is well above are laid on the young pjlants, and the larvae work their wayinto the stem at or near the surface, causing a slight gall or swell-ing and a deformity in plant growth. When winter sets in fullsize has been reached, and the flaxseed stage is enteredupon,—so called because of its superficial appearance, though itis really the brown, dry, and hardened larval skin itself. Inspring the pupa is formed, and soon afterwards the adult appears,ready to oviposit again in the now rapidly growing wheat. Theflaxseed stage is again formed low down in the stalk before har-vest, so that it usually remains in the stubble when the grain iscut. There it rests until the new wheat sprouts in fell, thoughflies may be found all summer, and it is more than likely that Fig. The Hessian-fly, Cecidomyia the left a healthy stalk of wheat and on thrn«ht one . at A by Hessian-fly, showing the galls. .,egg; ^ larva .Saxseed^, pupa, all very much enlarged ; .. fly ovipositing on leaf, natural size }, fen,ale a^.d Imale , enlarged ; .-, the parasite, Mcr^sus destructor, much enlarged 337 338 AN ECONOMIC ENTOMOLOGY. certain grasses also sustain the species in the interval betweenharvest and seeding. The injury is done by stunting and aborting the wheat plantsin the fall, and in dwarfing stalks in the spring or so weaken-ing them that they fall or lodge readily, preventing therebythe development of the ear or of the grain in it. Insecticide applications are hopeless, and modified farm practiceis the only satisfactory measure within our power. Very late sow-ing in the fall—^as late as it is safe to do so—
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectinsectp, bookyear1906
