ENTOMOLOGICAL SOCIETY OF ONTARIO. 91 



helpful to fruit growers there. The scale has been almost eradicated from several 

 orchards by means of it. Laboratory and field experiments now in progress promise hope- 

 ful results, but it does not seem probable that this disease will be of value in the northern 

 part of the United States, since warmth and moisture are necessary for its development. 



The next paper, treating of the same insect, was presented by Mr. Barrows : 



THE PRESENT STATUS OF THE SAN JOSE SO ALE IN MICHIGAN. 



So far as we have any knowledge, the San Jose scale first came to the notice of the 

 State Experiment Station May 14, 1896, when it was found on a single fruit tree in 

 Jackson, and the tree was destroyed soon after. The origin of the affected tree was not 

 ascertained, and as no other occurrences were reported from the vicinity it was supposed 

 that no further trouble would result. In December following, however, it became evi- 

 dent from its invasion of the States adjoining Michigan on the south that our own State 

 was in serious danger, and on application to the New Jersey nurserymen who were sup- 

 posed to have sent out infested stock, a list of several hundred Michigan addresses was 

 received by the horticulturist of the station, and a circular letter describing the scale and 

 its work was sent to each address. Comparatively few replies to this letter were 

 received, but among them were some which indicated the presence of the scale, and fur- 

 ther enquiries showed its presence in several places. 



During the winter many different parts of the State were visited in quest of the pest, 

 but the severe weather, the lack of time, and especially the' number and extent of the 

 suspected orchards, made anything like thorough inspection impossible. The scale was 

 located in greater or less abundance at half a dozen widely separated points, and this 

 number has been increased by as many more through correspondence and the transmis- 

 sion of specimens. At present the scale is positively known to have existed in the ten 

 counties, and in no case is there positive proof that it has been entirely eradicated. 



In Ottawa County the infested stock was received from New Jersey in the spring of 

 1890, and thus had been established almost seven years before it came to the knowledge 

 of any entomologist. During this time it had killed all or nearly all the trees on which 

 it was brought, and had spread to all the other fruit trees in the immediate vicinity, some 

 of which also had succumbed. Probably at this place several acres were badly infested, 

 and of course it is to be feared that the scale has been carried to other orchards in the 

 neighborhood. 



In Ingham County one locality was found in the city of Lansing where the fruit 

 trees about two houses and in their gardens were badly affected, and the scale had over- 

 run rose bushes, currant bushes, grape vines, and even one or two shrubs of Spirse*. In 

 this case the scale was originally brought on pear trees which were bought from a resi- 

 dent dealer in 1888 or 1889. The trees were said to have been obtained in New York 

 State, but, as the dealer is known to have been unreliable, and as very few trees were 

 true to name, it is not likely that any dependence can be placed on the statement. It is 

 more than probable that the stock came from New Jersey, and that other parties in the 

 vicinity have introduced the scale through the same dealer. 



In still another case (and county) a dealer is known to have handled stock which 

 was infested with the scale, and that at least five or six years ago, so that it is fair to 

 assume that this pe3t is now pretty widely and thoroughly distributed through the fruit- 

 growing parts of the State, and we may expect to find it in large quantities in all the 

 counties of the four southern tiers, and yet farther north along the west side of the State. 

 Since the scale thrives in Ingham and Ottawa counties it is likely to winter safely still 

 farther north, and as yet the life zones in Michigan are so poorly defined that it is impos- 

 sible to draw any line beyond which we may safely predict that the scale cannot live. * 

 * When we know more of the geographical distribution of life in Michigan, it 



may be possible to define with precision the limits beyond which the San Jose' scale will 



