REPORT OF THE STATE ENTOMOLOGIST Hjl6 5'j 



As a result the twigs and buds were very satisfactorily coated with 

 a Lime-sulphur wash; in some instances the crevices between the 



bud scales were full of the mixture. 



An examination of this orchard on May ist showed that the trees 

 were very well covered with the wash, the trunks and branches 

 being markedly whiter than those sprayed with an ordinary lime- 

 sulphur wash and the buds were mostly well covered and decidedly 

 later than was the case with unsprayed trees. There were a few 

 dead buds on the treated trees, this being especially true of the 

 smaller buds containing a single blossom. One or two insects were 

 not uncommon in blossom clusters here and there, though the 

 infestation was not nearly so serious as in a nearby orchard sprayed 

 later with a lime-sulphur wash containing decidedly less lime. Later, 

 May ioth, it was estimated that there was very little injury in this 

 experimental orchard, probably 5 per cent of the buds being killed, 

 certainly not over 10 per cent. Near a large apple tree and close 

 to the experimental plot, there was one pear tree which, it was stated, 

 had been sprayed as thoroughly as the others, though its appearance 

 hardly bore out the contention. This tree showed a very serious 

 infestation by thrips, over 90 per cent and perhaps 95 per cent of 

 the buds having been killed. This tree was, however, hardly repre- 

 sentative of the infestation of the experimental area. 



Other experiments with this wash were started but the results 

 were not decisive owing to the appearance of but small numbers 

 of thrips. 



Early spraying with a lime-sulphur wash containing a considerable 

 excess of lime is one of the most promising methods of controlling 

 pear thrips by one application. The treatment should be given 

 before the buds have started or " cracked " to any extent, and an 

 effort made to cover every bud thickly with the lime-sulphur wash. 

 This seems not only to exclude the insects but to check the develop- 

 ment of the buds until with w T armer weather they unfold very rapidly 

 and thus, in a measure at least, are«able to outgrow thrip injury. 

 An important advantage of this treatment is that it also controls 

 San Jose scale though it is a little early for pear psylla. It can be 

 supplemented, however, in case thrips are extremely abundant, by 

 the application of the tobacco-soap preparation at the time the 

 blossom clusters have separated. 



