EXPERIMENT STATION REPORTS. 185 



Grape-berry moth. — For several years increasingly insistant complaints 

 have been coming in, accusing the grape-berry moth of causing serious losses, 

 and in response to this demand a special effort was made to determine some 

 more effective method of control or at least to time the customary sprays, 

 so as to obtain the highest efficiency. In cooperation with County Agent 

 W. C. Eckard, and with the aid of Mr. Hain of this section and Mr. T. 

 A. Farrand of the Section of Horticulture, a good deal of publicity was 

 given the matter and quite a measure of success seems to have resulted, at 

 least so far as the first generation of moths goes. 



Grape leaf-hopper. — Following the crusade against the grape-berry moth, 

 in the same part of the State there appeared a wide-spread and serious out- 

 break of leaf-hoppers, Typhlocyha tricincta, and at the present moment the 

 grape growers are just finishing with their spraying in an attempt to gain 

 control over this pest. The proper timing of this spray is important as well, 

 since it is almost useless to apply the spray after the hoppers attain wings 

 and also almost impossi])le to kill tlie eggs, so that the time for optimum 

 results is just before the first nymphs attain their wings, which time will be 

 before all the eggs have hatched. For this purpose a combination of Bordeaux 

 and black-leaf forty with soap, seems to be most effective. 



Pear psylla. — Late in the winter it became apparent that the pear psylla 

 which had for several seasons been getting worse and worse was going to be 

 more troublesome than ever before. This condition had arisen because of 

 the open winter during which the psyllas had spread all over the farms, in 

 orchards and elsewhere. It was apparent that no spraying operations would 

 be effective if applied against the adult insects since they were scattered so 

 widely, but it was reasoned that the eggs would all be laid on the pear trees 

 themselves and that an egg spray would be especially desirable if such a thing 

 existed. At this time Mr. Button of the Department of Horticulture brought 

 in a supply of adult psyllas which were induced to lay their eggs on pear 

 twigs in our cages. These twigs were subsequently treated with several spray- 

 ing materials and the effects noted during the winter time. Finally lime-sul- 

 phur was selected as being the most promising of all the sprays and it was 

 recommended that lime-sulphur, one to seven, be applied just as the blossom 

 buds separate into clusters in the standard varieties. This was accordingly 

 done in a number of cases, through the agency of Mr. Button, and apparently 

 with good results, although in many cases Kiefer buds were killed, being at 

 that time too far along for a spray of such a drastic nature. However, the 

 death of the buds in this one variety seems to be less of an evil than the 

 almost certain loss of the crop and possibly of the trees if no chances were 

 takc;n and no spray applied. 



Fruit tree leaf-roller. — An insect considered as a serious pest in the West and 

 one that has been claiming some attention in Michigan lately, in a few locali- 

 ties, is the fruit tree leaf-roller, Archips argyrospila. In certain orchards near 

 Muir it has been almost impossible to protect the trees. An attempt was 

 made this year to kill the eggs of this pest by a spray of scalccide put on early, 

 just before hatching. The owner was advised to use it at the rate of one part 

 of scalecide to twelve and one-half of water. The spray was applied at the 

 time when the leaf buds burst and with pretty fair success, since the number 

 of living worms was very much reduced over those of previous years. In this 

 case as in others, egg-masses were collected in the winter and treated in cages 

 here in our insectary, with the various washes which seemed most promising 

 and then the one giving best results was selected for treatment. 



