SOME SCALE INSECTS. 85 



liable to be iatroducecl into the State upon niirser}' stock, and 

 which will certainly flourish here if once introduced. 



In speaking of the State of Massachusetts as a whole it must 

 be remembered that the same conditions do not prevail over the 

 entire State. Yon have a double watershed from an elevated 

 north and south ridge, passing through the vicinity of Worcester, 

 sloping gradually towards the eastern seacoast in one direction 

 and towards the valley of the Connecticut river in the other. 

 West of the Connecticut river there is a more abrupt rise to the 

 Berkshire hills, and thence a descent of almost equal abruptness 

 to the valley of the Hudson river in New York. It results from 

 this conformation that more southern forms are found in a com- 

 paratively narrow strip up the valley of the Connecticut river 

 and to a lesser extent up the seacoast, than in other and more 

 elevated portions of the State ; and experience has shown that 

 certain insects will establish themselves in these strips which 

 will not continue to reproduce and multiply when accidentally 

 introduced into other Massachusetts localities. This principle, 

 which is now fairly well established, has especial significance in 

 considering the question of the possible future damage in Mas- 

 sachusetts by two of the most important scale insects injurious 

 to fruit trees ; I refer to the San Jose scale and the so-called 

 West Indian peach scale. So far as our experience goes (and this 

 experience may be said to be based upon more than negative evi- 

 dence) neither of these species will prove itself especially injuri- 

 ous in regions Avhich belong to the transition life zone, which 

 includes all of Massachusetts except the strip mentioned. It is 

 even likely that both species will die out if introduced at any 

 point in this life zone. 



The San Jose scale, as you know, was brought from California 

 on the Kelsey plum, to two large nurseries in New Jersey — 

 those of Parry Bros., at Parry ville, and J. T. Lovett, at Little 

 Silver — in 1886 or 1887. The trees were undoubtedly thoroughly 

 infested when received ; did not thrive ; and in both cases most 

 of them were ultimately taken up and destroyed. The stock, how- 

 ever, had been multiplied by nursery methods, and from the origi- 

 nal stock and that subsequently obtained, the scale spread more 

 or less completely through both nurseries in question. Now, 

 from that year until 1893, both these nurseries (and as you 

 know, both, during that period, did an enormous business) sent 



