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Show State Hopper Pest Studied By Experts Trained entomologists are now go-' 'ng through the fields of every county coun-ty in Utah to determine the adult living liv-ing grasshopper population now existing, according to Dr. W. W. Henderson Hen-derson of the Utah State Agricultural college. The population now actually in evidence is one reliable indication of what the population will be next year. , i These entomolog'sts art trained to estimate accurately the live population popula-tion in any field. If there are only two or three grasshoppers per square yard, it will be safe to say the grasshopper grass-hopper population next year will be normal and that injury to crops will not be noticeable. If there are six to eight per square yard, there will be a medium infestation of grasshoppers next year, with considerable injury to crops. If there are 12 or 15 or more per square yard, there wil be a heavy infestation next year, which may amount to total destruction of crops. Another check on the possible grasshopper infestation for next year is to make a study of the, egg deposits in the soil. The entomologist recovers the grasshopper egg capsules laid in the soil, by a reliable method of sampling and, after long experience,! is able to use this "shadow" to dis-j cover the coming year's grasshopper; events. To determine the extent of egg-deposition one crosses a field, say of alfalfa, in the fall after harvest har-vest and with a sharp spade takes up a six-inch squre of surface soil every few rods, sifting it through a quarter-inch mesh sieve. Th's sieve will retain the egg capsules if there are any. One crosses, say a ten-acre field, by one route and back by another. Then he examines the borders and roadways in the same way. If by this sampling method a great many, very few, or no egg capsules are found one has a good and reliable index to grasshopper population th next year for that field. If a dozen or two of the most likely fields of the county are thus carefully sun-eyed, this sampling becomes a reliable index. Those who are conducting the survey, sur-vey, which is in cooperation with the federal government, are: Dr. Henderson, Hender-son, Professor C. J. Sorenson and Dr.' George F. Knowlton of the U. S. A. C. |