February, '14] matheson: nova scotia scale conditions 143- 



is no data regarding the winter mortality. Experiments have been 

 started at Truro, N. S., on the effects of climatic conditions on this 

 scale but no results are as yet available. During the past summer 

 scale-infested trees were under constant observation and the number 

 of generations up to the first of October was carefully observed. The 

 first adult male was taken in our outdoor breeding cage, which consisted 

 of four partially infested young apple trees enclosed in wire netting 

 so as to prevent distribution, on June 23. The spring was cold and 

 backward but the female scales were growing rapidly and many male 

 pupse were ready to transform. On July 26 the first living young were 

 observed and within the next ten days many of the young lice could 

 be seen crawling over the trees and settling down. The weather 

 during the latter part of June was very cold, a severe frost on the 22d 

 having destroyed many tender plants and here and there young potato 

 plants. The first generation were hatching in abundance about 

 August 7. The trees were now becoming well covered with the matur- 

 ing scales. On August 22 we had another sharp frost kilhng such 

 plants as tomatoes, squash, cucumber, corn, and in some places black- 

 ening fields of maturing potatoes. However, the scale seemed to 

 thrive and the second generation began moving about September 3 and 

 continued abundantly for the next four weeks. On October 12 young 

 lice were still hatching but whether this was the last of the second 

 generation or beginning of the third I^ could not determine. How- 

 ever, the season of 1913 was an exceptionally cool and backward one 

 in Nova Scotia, a similar one not having been experienced for many 

 years previously. The spring was late and cold Avhile severe frosts 

 occurred late in June and rather early in August, a condition seldom 

 occurring. Yet despite this there were two full generations of the 

 San Jose scale and I feel that under normal conditions there will always 

 be at least a partial third generation. As to whether the majority of 

 the scale will winter or not is yet to be learned. The minimum tem- 

 perature at Truro, N. S., rarely goes to — 25° F. though during the 

 winter of 1912-1913 the lowest recorded was- 27° F. 



Following the discovery of living San Jose scale, active measures 

 were at once taken by M. Gumming, Secretary for Agriculture. For- 

 tunately an insect pest law, drawn in broad terms, had been enacted 

 in 1911 and under its provisions a thorough inspection of all nursery 

 stock imported during the years 1910, 1911 and 1912 was begun. 

 Lists of consignees were obtained from nearly all the nursery firms that 

 had done business in the province. These lists furnished a basis for 

 the work. Mr. George E. Sanders, of the Dominion Entomological 

 Staff, took charge of the work and pushed it energetically. The 

 results of this work are shown in the following pages. 



