22 



EXPERIMENT STATION. 



[Jan. 



Avliolc bog-, than there is on a long, narrow one of equal acreage, may 

 also be, to some extent, a factor in favor of this insect. If it 

 gained a foothold on one portion of such a coin2)act bog, it would more 

 readily and (luickly sjjread to all other i)orlions. 



It seems probable, from the various observations made, tliat if a large 

 bog, round or squarish in shape, is by any means wliatever entirely 

 freed from this insect (even by burning or by long-coniinued summer 

 flowage), it will not, as a rule, long remain so if all the following 

 conditions ai'e allowed to exist : — 



1. Winter flowage, especially if it is deep, over a considerable por- 

 tion of the bog. 



2. Not more than one reflowage after the 25th of May. 



3. Conditions favoring heavy vine growth. 



New Pests. — During the season two new insect pests did considera- 

 ble injury in some localities on cranberry bogs. One of these is a scale 

 insect {Aspidiotus oxycoccus Woglum) which superficially resembles 

 the San Jose scale somewhat but is very distinct from that si^eeies. 

 This species did much injury on a bog in Yarmouth and was noted 

 in smaller numbers in a few other places. 



Tiie other insect is a species of white grub (Lachnosterna sp.). It 

 caused the dying of circular areas on several bogs, principally in 

 Carver, these patches varying in diameter from 3 to 30 feet. This 

 injury observed superficially might easily be mistaken for the " ring- 

 worm " injury caused aiJi)arently by fungous disease. 



2. Fungous Diseases. 

 This work, as during the previous season, was done in co-operation 

 witli the Bureau of Plant Industry. Co-operative spraying experi- 

 ments were carried on by several i>ractical growers. In addition 3 plots 

 on the station bog, each 4 rods square, were sprayed with fungicides 

 and the results noted, as shown by the quantity and keei)ing quality 

 of the fruit obtained. The amount of fruit gathered from these plots 

 in every case was somewhat less than that from checks marked on the 

 surrounding bog. This was due, apparently, to the injury done by 

 tramj>ing on the vines while spraying. Loss due to decay up to Decem- 

 ber 4 was reduced, on an average, about one-half by the treatment. 

 One i)lot was sprayed three times and the others twice with mixtures 

 and on dates as follows : — 



