62 STATE HOUTH'L LTLUAL StX'IETY. 



The dormant application should be followed after the blossoms fall by 

 another application of nicotine sulphate in order to get any that escaped 

 the first application. The nymphs of the first summer brood will be 

 on the trees at this time. 



Another schedule treatment has been used in some districts and was 

 recommended in this state last spring by the Entomological and Horti- 

 cultural Departments. This schedule consists of an application of 

 strong lime-sulphur when the blossom buds are read}' to separate in 

 the cluster and is directed at the eggs which are mostly laid at this time. 

 In order to determine just what strength of material was necessary and 

 safe to use, I secured from Fennville during the winter a large number 

 of hibernating psylla and took them to Professor Pettit who put them in 

 cages with pear twigs in the insectar3^ He made conditions as much 

 like spring as possible and the psylla laid great numbers of eggs on the 

 pear twigs. These twigs were separated into several groups and each 

 group was dipped in a different material. Some of the materials used 

 were lime-sulphur at different strengths, lime-sulphur and lime, lime- 

 sulphur and starch, lime-sulphur and Black Leaf 40, Scalacide, and 

 dry lime-sulphur. 



Lime-sulphur at the rate of 6}4 gallons in 50 or at a slightly weaker 

 strength with hydrated lime added, gave the best results. Dry lime- 

 sulphur, Scalecide and lime-sulphur with Black Leaf 40 were not so 

 successful. I may say now that Professor Pettit and I expect to con- 

 tinue this work this winter and get all the information possible. 



The exact time to make this application might vary under differ- 

 ent conditions; but considering the entire spraying schedule for pears, it 

 seems that the best time is w4ien the blossom buds are in what we may 

 call the "pre-pink" stage. This is specially true where pear scab is 

 serious as I have been recommending a prepink application for scab 

 control and the strong lime-sulphur put on at this time is an excellent 

 scab preventive. It is also an excellent time to spray for scale insects 

 and pear leaf blister mite should be reduced by it also. This applica- 

 tion would, if made a little later when the buds have separated in the 

 cluster be effective against more eggs as they are not all laid at the earlier 

 stage and in fact they may not all be laid before full bloom and it is 

 because of this that the application after the blossoms fall is necessarj'. 



Some growers have asked if the strong lime-sulphur at this time will 

 injure the buds. It wdll burn the small first leaves which come out 

 around the blossom cluster but the loss of these has never been serious 

 and the trees will not show^ any permanent injury. With normal weather 

 conditions it is not probable that it would injure the buds even in full 

 pink but with frequent frosts as we had last spring, there seemed to be 

 a combination of spray and frost injur3^ This was particularly true with 

 Kieffer. They open earlier and seem to be more tender than other 

 varieties and if the application were timed for an average of all varie- 

 ties the Kieffer would be too far out. The best practice then, is to 

 spray each variety according to its bud development. 



There should then be another application after the blossoms fall with 

 nicotine sulphate and soap or it may be used in combination with limo- 

 sulphur and lead arsenate without the soap. When used in combina- 

 tion with lime-sulphur and lead arsenate the addition of ten pountls of 

 hydrated Ume to each one hundred gallons has been helpful in some 

 instances. 



