. Bulletin of the Department of Agriculture. Agriculture. CODLING MOTH IN COLORADO. 11 pupation of 320 larvse are given in Table III and illustrated in fi<2:ure 1. It will be noted that the earliest pupation occurred April 14, when two larvse transformed, and that the last of the wintering larvae pupated June 8 or approximately 8 weeks later. On April 26 there was a marked increase in the rate of pupation and a still greater increase two days later, owing to higher temperatures, as shown in figure 1. Following this activity the temperatures became abnor- mally low, reaching in the inse
. Bulletin of the Department of Agriculture. Agriculture. CODLING MOTH IN COLORADO. 11 pupation of 320 larvse are given in Table III and illustrated in fi<2:ure 1. It will be noted that the earliest pupation occurred April 14, when two larvse transformed, and that the last of the wintering larvae pupated June 8 or approximately 8 weeks later. On April 26 there was a marked increase in the rate of pupation and a still greater increase two days later, owing to higher temperatures, as shown in figure 1. Following this activity the temperatures became abnor- mally low, reaching in the insect- ary a minimum of 27° F, on May 2, on this date only one larva pupating. This freeze contributed largely to the destruction of prac- tically the entire fruit crop of the Grand Valley west of the Pali- sade district. Freezing tempera- tures recurred on the mornings of May 3, 4, and 7, but on the latter maximum of 70° F., and, as a result, 18 larvse pupated. Pupation thereafter continued quite regularly (except on May 10) and reached its maximum on May 12. During the period of one week, May 7 to 13, inclusive, approximately 40 per cent of the wintering larvae pupated. Following this crest of activitj^ the rate of pupation gradu- ally diminished in the normal 'I J J/ y I i\b5B Fig. 1.—Time of pupation of spring- brood pupsB of the codling moth,. Grand Junction, Colo., 1915. date the temperature reached a Table III.—Time of pupation of lointering larx^cB of the codling moth, Grand Junction, Colo., 1915. Date of Num- Date of Num- Date of Num- Date of Num- Date of Num- pupa- ber of pupa- ber of pupa- ber of pupa- ber of pupa- ber of tion. pupse. tion. pupae. tion. pupse. tion. pupae. tion. pupip. Apr. 14 2 Apr. 26 13 May 8 19 May 20 1 June 1 1 15 0 27 8 9 13 21 1 2 1 16 1 28 25 10 4 22 1 3 0 17 0 29 13 11 26 23 5 4 1 18 2 30 11 12 30 24 4 5 0 19 2 May 1 4 13 20 25 2 6 0 20 3 2 1 14 12 26 2 1 21 7 3 3 15 10 27 2 8 2 22 23 0 1 4 5 3 1 16 17 8 7 28 29 4 2 320 24
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