. Bulletin of the Department of Agriculture. Agriculture. 18 BULLETIN 926, U. S. DEPAKTMENT OF AGRICULTURE. When the thermometer was wrapped in cool,, green leaves it regis- tered 89° F., but when inserted into a square and wrapped in green leaves it registered 81°. The thermometer covered one-fourth inch by hot sand in the sun registered ° to ° F.; under one-half inch of sand it regis- tered 99°, under 1 inch 95°, and under 1| inches of sand 91°, Thus shallow burial of infested squares would merely give the immature weevils more favorable temperatures and almost insure emergenc
. Bulletin of the Department of Agriculture. Agriculture. 18 BULLETIN 926, U. S. DEPAKTMENT OF AGRICULTURE. When the thermometer was wrapped in cool,, green leaves it regis- tered 89° F., but when inserted into a square and wrapped in green leaves it registered 81°. The thermometer covered one-fourth inch by hot sand in the sun registered ° to ° F.; under one-half inch of sand it regis- tered 99°, under 1 inch 95°, and under 1| inches of sand 91°, Thus shallow burial of infested squares would merely give the immature weevils more favorable temperatures and almost insure emergence; while the sun-heated surface soil, even on this moderate day, was heated very close to a fatal -Outdoor insectary, Madison, Pla., wherq the records were secured to check against the field records. Dr. Pierce then studied the temperature in the field breeding cages and found in the oviposition cage an air temperature of 85° F., a soil temperature in the sun of 108° to °, in the shade of the wire screen 90° to °, and in the shade of the plant 92° to 95°. The humidity in the cage was per cent, wet bulb 85, while in the open air it was per cent, wet bulb There is therefore very little difference in the temperature in and out of the cage. The small wire-screen cages used to cover the squares during the last two days before emergence were then measured. In the shade of the plant the temperature was ° to ° F. and in the sun 103° to 106°. The cage, therefore, serves to mitigate slightly the intense heat. In the insectary measurements were made in the breeding tumblers. A temperature of ° F. was recorded for the soil in the tumblers, while above the soil the temperature was ° F. Since the tumblers were only moistened once during the hatching period, a temperature. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearan
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