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NEW YOUK STATE MUSEUM 



This pest is most easily controlled by thorough spraying with a con- 

 tact insecticide such as a whale oil soap solution or a kerosene emulsion, 

 taking special pains to hit the insects before they can jump out of harm's 

 wa\'. The adults are somewhat difficult to destroy and where thorough 

 work is necessary it may be advisable to knock them to the ground with a 

 weaker spray and then complete the work by drenching them with a stronger 

 solution. Thorough spraying with a powerful jet of water from a hose has 

 been found very effective in keeping this pest in check, and where such 

 is available, recourse to the disagreeable insecticides will probably be 



unnecessary. 



Woolly elm bark aphid 



Scliizonciira rilcyi Thos. 

 Clusters of a white, woolly substance on limbs and tnmks of white elms, accompanied 

 1)V a knotted, unnatural growth of wood, are very likely the work of this species. 



This insect is widely distributed in the State, and here and there badly 

 deformed trees are met with as a result of the operations of this plant louse. 

 It does not, as a rule, cause much injury. The lice are met with on the 

 trees in May, June and possibly later, anil as they are easily seen it is not 

 difficult to control them, since they can be killed, according to Dr Riley, 

 with a weak solution of cresylic acid soap. It is very probable that thor- 

 ough spraying, particularly if a forcible s])ra\' be employed, with either 

 whale oil soap emulsion or a carbolic acid and soap emulsion would destroy 



them as rcailih". 



Pine bark aphid 



Clici Dies piiiicortiiis Fitch 



Patches of flocculent downy matter may be observed on the smooth bark of white 

 jiine and these will be found to conceal minute ])lanl lice. 



This insect appears to be a .somewhat common one on pine growing in 

 parks and under somewhat artificial conditions in New York State. The 

 writer has observed the work of this species for a number of years in 

 Washington park, Albany, where it has frecpienlly been so abimdant as to 

 literally cover the smooth bark of a consideralilc proportion of the trunks 

 of certain young white pine. The presence of large numbers of this insect 



