. Circular. Insect pests; Insect pests. 11 acres. In one of these it was determined to introduce enormous numbers of parasites artificially, keeping records of this field for comparison with the other field in which no introductions were made, thus determining the measure of benefit, if any. which resulted from the artificial introduction. Mr. Ainslie was instructed by wire to sliij) from Wellington, Ivans., (') bushels of the wheat plants that had been. Fl( -Stalk of wheat, the leaves covered with dead " green bugs " killed liy the parasitt LyftiphJehus tritici. About natural size â
. Circular. Insect pests; Insect pests. 11 acres. In one of these it was determined to introduce enormous numbers of parasites artificially, keeping records of this field for comparison with the other field in which no introductions were made, thus determining the measure of benefit, if any. which resulted from the artificial introduction. Mr. Ainslie was instructed by wire to sliij) from Wellington, Ivans., (') bushels of the wheat plants that had been. Fl( -Stalk of wheat, the leaves covered with dead " green bugs " killed liy the parasitt LyftiphJehus tritici. About natural size â (original». destroyed by the " green bug " and which, in some cases, were literally covered with the parasitized bodies of the pest, upward of 500 having been found on a single plant (see fig. 5). Before taking up the experi- ment, however, it Avas desirable to know just what the conditions were under Avhich it was begun. As stated above, one of these oat fields was used for the experiment of introducing parasites, while the other Avas kept as a check. The fields Avere so widely separated that the intro- [Cir. 93]. 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 not perfectly resemble the original United States. Bureau of Entomology. Washington, D. C. : The Bureau
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