THE MONTHLY BULLETIN. 507 



partially tnu-. When first blighted the blossom cup fills with a milky 

 liquid whii'h is not unlike sap and is, therefore, not distasteful to flower- 

 visiting inseets. 



This gum retains its edible qualities much longer than lateral exudate, 

 prol)ably because of its association with the nectar of the flowers, and is 

 largely sought for several days after the first symptoms of blight. The 

 flower seldom begins to wilt until after the disease has reached the pedicel 

 ])elow the bulbous seed pod, and as it passes through this the entire 

 exudate appears in the cup, Avhich is the most natural outlet on account 

 of its lack of cuticle. There are many other insects that may be classed 

 with the bees, such as the Bombyliids, or bee-Hies and syrphid files, that 

 feed from the nectar of the flowers. 



Where there has been much holdover blight and early spring infection 

 is abundant, these insects do enormous injury in curtailing the crop, as 

 well as in actual damage to the trees themselves, where blight descends 

 into the larger limbs. 



Flies as Pear Blight Carriers. 

 In the ease of pear blight the connnon flies, as we know them about the 

 farm lot, are quite as uuich of an abomination out of doors as they are 

 indoors. Few insects are more responsible than they for the transmis- 

 sion of winter blight to the blossoms. But their depredations do not 

 end with this, for while they are present in the early spring they remain 

 throughout the sunnner. The great injury due to them is largely by 

 reason of their omniverous feeding habits, their diet ranging throughout 

 the animal and vegetable kingdoms, and including almost every type of 

 food that is available to their peculiar mouth structure. They are 

 attracted to gummy exudate as readily as to table syrup, and it is never 

 too badly fermented to l)e distasteful to them. They are fond of the 

 nectar of the flowers. If a blighted pear be cut open it will be found 

 to contain a quantity of milky liquid which has a very marked odor. 

 If the pieces of this be placed on the ground a group of flies will soon 

 collect about them, and a fly is a detective of rare ability. He will find 

 the smallest blighted twig, whether in the tree or cut off and cast upon 

 the ground, and after feeding upon it is ready to go' on his destructive 

 way. The moral is : Do not leave the twig in the tree or on the ground ; 

 cut it off and burn it up. 



Pear Blight Carried by Ants. 

 Formicids or ants are similar to flies in their fondness for blight 

 exudate, and also for the persistent vL-^its to the flowers. Their destruc- 

 tiveness as promulgators of blight is greatly enhanced by their social 

 habits. A solitary ant, finding a case of gumming blight, often notifies 

 others of the colony, and soon there is a perpetual train of them going 

 to and coming from the dangerous gum. Because of their association 

 with the aphids and also because of their habits of feeding from the 

 flower cups, they are always in and about the trees in great numbers. 

 jNIany groAvers have expressed the belief that their twig infection was 

 due to ants, but, with the exception of an occasional gnawing upon the 

 stamens or pistils of the flower in their search for nectar, I have never 

 seen them feeding upon pear foliage except in the situations mentioned 

 above. 

 8—14209 



