1923.] PUBLIC DOCUMENT — No. 31. 15a 



Entomology Project 9. "Number of generations of codling moth in Massa- 

 chusetts as related to advisability of spraying for the second generation." 



Assistant Professor Bourne. 



The accumulation of data on the codling moth has now reached a point where, with 

 good fortune, final results may be anticipated in the course of two or three seasons. 

 Co-operative work with a fruit grower in the Nashoba fruit district has added value to 

 the work, giving a broader knowledge of conditions in Massachusetts. 



Entomology Project 10. "Hatching dates for scale insects." 



Assistant Professor Bourne. 



The necessary observations for 1922 have been made and recorded. To be of value, 

 these records should be made over a long period of years, to insure inclusion of years of 

 abnormal conditions as well as normal ones. The behavior of the insects under normal 

 conditions has been determined with considerable accuracy. Their reaction to abnormal 

 seasonal conditions, such as very open, mild winters, or unusually cold winters, makes 

 further study advisable. Records on other points in the life cycle of the.se scales have 

 been secured, with especial reference to the possibilities of their furnishing more accurate 

 data on this problem. 



Cranberry Station Project 1. "Injurious and beneficial insects affecting the 

 cranberry." 



Professor Franklin. 



The more important results of the year's operations were the following: 



A very effective control for the root grub {Amphicoma vulpina Hentz.), by soaking 

 the soil with a solution of sodium cyanide, was developed. 



A satisfactory^ control for the j^ellow-head fireworm {Peronea minula Rob.) by killing 

 the moths with a spray of nicotine sulfate and soap in the dormant season was perfected. 

 Experiments also showed that this pest can be controlled with a lead arsenate spray 

 used at the time and strength to be most effective against the gypsy moth. 



It was found that the red-striped fireworm (Gelechia trialbamaculella Cham.) can be 

 controlled well with a nicotine sulfate and soap spray applied while the worms are in the 

 tips of the vines. 



Dusting with nico-dust to control the black-head fireworm (Rhopobota naevana Hiib- 

 ner) proved effective but not practicable because of the expense. 



Extensive spraying experiments to discover a cheaper control for black-head fireworm 

 were conducted, with mostly negative results. 



A fungus, apparently a new species of Entomopthora, was found causing such an epi- 

 demic among the black-head fireworms on one bog that it seemed an almost perfect 

 control. The fungus was successfully cultured on fish. It presents interesting possi- 

 bilities for further control work. 



Important observations were made on the phenomenon of the occasional marked 

 disappearance of black-head fireworm eggs while covered by the winter flood. 



IVlany new facts were learned concerning the life histories of the following minor cran- 

 berry pests; 



1. Cacoecia parallela Rob. 



2. Sparganoihis sulfureana Clemens. 



3. Noclua c-nigrum L. 



The work of the fruit worm (Mineola vaccinii RUey) was observed to be light in spite 

 of the fact that the egg parasite (Trichogramma minuta) was much less prevalent than 

 normally. The egg hatching of this pest was earlier than usual, so the worms did little 

 harm among stored berries. Further attempts to discover a practicable means of con- 

 trol by wetting the cocoons with chemicals during the dormant season resulted nega- 

 tively. 



Plant Disease Control. 



_ Botany Project 3. "Tobacco investigations and a study of so-called tobacco 

 sick soils." 



Professor Osmun and Professor Anderson. 



This project embraces a study of soil reaction as a means of controlling root-rots of 

 tobacco; also a study of the effects of soil reaction on the growth and development of 



