THIRD ANNUAL REPORT OF STATE ENTOMOLOGIST. 213 



GEOGRAPHICAL DISTRIBUTION. 



As indicated by the published records, the plum gouger occurs 

 throughout the north-central portions of the United States. It 

 extends from Montana east to Michigan and New York and south to 

 Texas. It is probable that in the territory here roughly indicated 

 that this beetle has lived in a natural state for centuries before white 

 men came to America. In fact, the beetle is believed to be native 

 to this region. 



In this connection it is interesting to note the geographical 

 distribution of the native plum of America, Primus americana, 

 as given by Waugh in his "Plums and Plum Culture," (1901). He 

 says "In its native forms the species Primus americana ranges from 

 Ohio to Texas and northward to ^linnesota and Montana. Along 

 the northern border of this range and eatsward in New York state 

 it shades away insensibly into Pniiiiis americana nigra, (the nigra 

 group). Thus, in general terms, the distribution of the gouger is 

 the same as Prunus americana. The coincidence of the distribution 

 of the two may or may not indicate that the plum mentioned is the 

 only food of the gouger. The insect is known to feed in the orchard 

 from plums whose origin is other than from the American wild plum 



Professor "\\'augh also states that, horticulturally, the American 

 plums range from Prince Edward Island, IManitoba and A^ancouver 

 to Florida, Louisiana and Texas. 



Over a large area, however, especially in Northern Iowa, Wis- 

 consin, northern ^Michigan, Minnesota to the Dakotas, Montana and 

 that part of Canada between Ontario and Vancouver, they are 

 practically the only plums that can be grown. 



It is apparent, therefore, that this very destructive insect is 

 likely to become very much more widespread in its occurrence than 

 at present, maturing, as it does, in a relatively short period. It will 

 probably be able to thrive in a much more extreme climate than 

 that of the parts of Montana it now occupies and will extend its 

 existence into other localities. 



