. The pear thrips (Taeniothrips inconsequens Uzel) and its control in British Columbia [microform]. Pear thrips; Insect pests; Thrips; Insectes nuisibles, Lutte contre les; Thrips du poirier; Thrips. 29 EMERGKNCE OF ADILT8 IN HELATION TO TEMPERATIRE. The records for the years 191G and 1917 go to prove that the critical temperatures which determine the emergence of the adults from the soil in the spring, are 45 degrees Fahr. for the soil and 50 degrees Fahr. for the air. Should the temperature at any time fall below these figures after the emergence has aetually commenced, the effect will he to
. The pear thrips (Taeniothrips inconsequens Uzel) and its control in British Columbia [microform]. Pear thrips; Insect pests; Thrips; Insectes nuisibles, Lutte contre les; Thrips du poirier; Thrips. 29 EMERGKNCE OF ADILT8 IN HELATION TO TEMPERATIRE. The records for the years 191G and 1917 go to prove that the critical temperatures which determine the emergence of the adults from the soil in the spring, are 45 degrees Fahr. for the soil and 50 degrees Fahr. for the air. Should the temperature at any time fall below these figures after the emergence has aetually commenced, the effect will he to delay the process and to give a double or treble maximum to the curve of emergence. On the other hand, should the temperature Ije maintained above the critical point for some time, a graphical representation of the emergence will show l)ut one maximum. 'i?. Fig, 12,âStraight-liiif cun-t- showiiw cmrrKcnrr of aduit p«ar tliiip:, m trap ciwea under trees in onlmrd, Royal Oak. Vancouver island, March 2S-April 25. Dotted cur\-e is a graphical representation of the average daily mean soil temperature during the same perio;i. ((Jrii?inal). It will be observed that the curve of emergence for 1917 at Royal Oak, Vancouver island, (fig. 12) has three distinct phases, between the dates of March 4 to 10, due to the variations of soil temperature. On March 5, 7, and 9, the emergence was notal)le by reason of the large numbers which deserted the soil when the temperature rose above the â . h. i". 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 Cameron, Alfred Ernest, 1887-1952; Treherne, R. C. (Reginald Charles), 1886-1924; Canada. Division of Entomology. Ottawa : J. de L. Taché
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectinsectpests, bookyear
