58 NEW YORK STATE MUSEUM 



unopened buds, and consequently spraying to be effective must be 

 early enough to catch the insects before there has been much dam.age 

 to either buds or leaves. 



Pear psylla (Psylla pyricola Forst.)- There have been 

 comparatively few reports of serious injury by pear psylla during the 

 past summer. The extremely severe weather of last winter following 

 injury by this insect and in some cases reduced vitality due to other 

 causes, has resulted in a great deal of winter injury. This has been 

 particularly marked in a number of pear orchards which have been 

 making an unsatisfactory growth for several years past and have 

 undoubtedly suffered to a greater cr less extent from pear psylla. 

 Trees in these orchards went into the winter in poor condition and 

 were unable to survive the extreme conditions. Small limbs and in 

 exceptional cases large limbs and in a few instances even most of 

 the trunk was practically killed or so badly injured that the trees 

 were unable to recover and slowly died back during the spring and 

 early simimer. Kieffer, Bartlett and Seckle trees fared the worst, 

 while Clapps favorite largely escaped damage. 



The pear psylla, it should be understood, is only one of a number 

 of contributing causes which weakened the trees in earlier seasons 

 so that they were unable to winter successfully. The severe weather 

 has emphasized this injury and fruit growers are coming to realize 

 as never before the need of keeping the trees vigorous if they are to 

 avoid serious damage. 



GARDEN INSECTS 

 White grubs (Phyllophaga fusca Frohl.) . The year for 

 serious white grub injury in Albany, Columbia and Rensselaer 

 counties, as well as some other portions of the State, passed with 

 little damage compared to the losses inflicted in 191 5 and 191 2. 

 There were some reports of local injury here and there but the affected 

 areas were by no means large and the injury could not be classed 

 as severe. 



It was hardly to be expected that these pests would be able to 

 continue in large numbers through a long series of years, though it 

 was not anticipated that there would be such a material diminution 

 of the insects. This favorable outcome is very probably due in 

 large measure to the activities of natural agents, such for example 

 as the predacious maggots of the robber fly, Promachus 

 fitchi 0. S., a species comparatively abundant in infested fields 

 in 1 9 13 and 19 16. Other natural enemies rendered material service 

 in destroying the grubs and even the adult beetles, though the proba- 



