GRAPEVINE FLEA-BEETLES. 
23 
Philadelphia vireo {Vireosylva philadelphica) , Carolina wren (Thry- 
othorus ludovicianus) , and hliiehird (Sialia sialis). 
METHODS OF CONTROL. 
As previously stated, no extensive iafestation of either species of 
flea-beetle eame under the writer's observation in the Erie-Chautauqua 
grape belt, and those infestations that did occur were confined to 
vines at the ends of rows or the edges of vineyards/ In such situa- 
tions hand-picking the beetles was the best rneans of control. The 
effect of this method is immediate, which is very desirable against 
so voracious an insect, against which arsenical sprays act comparatively 
slowly. On small areas in a corner or at the edge it is also cheaper 
than the employment of a power sprayer, which must be drawn the 
entire length of each row, of which only a small part may be infested. 
Had an extensive infestation occurred, spraying would have been 
resorted to, but as none was present no sprayiug experiments 
were conducted. 
The application of a spray mixture containing 3 pounds of arsenate 
of lead paste (1^ pounds, powdered) to 50 gallons of Bordeaux mix- 
ture is usually recommended for the control of the typical species. 
One of the recent investigators, Hartzell (24), states that this mixture 
protects the vines from severe injury because it is repellent to the 
beetles and disperses them over the vineyard, but that it does not kill 
them. To kill the beetles he has found that a high dosage of arsenate 
of lead, not less than 4 pounds paste (2 pounds, powdered) to 50 
gallons of water, is most effective. This high dosage is necessary 
to kill the beetles quickly before much damage is done, because of 
their voracity and resistance to poison. He also states that the 
effectiveness of the poison is much increased by the addition of 
one-half gallon of molasses to the foregoing mixture. The addition 
of molasses because of its solubility has the disadvantage, however, 
of making the poison likely to be washed off by rains. Owing to the 
frequency of rains at this season of the year this is a very serious 
disadvantage. Molasses sJiould not he added to a spray solution 
containing Bordeaux mixture, or burning of the foliage is apt to 
result. The- time of application should be on the first warm day 
when the grape buds are swelling, or as soon as the beetles appear. 
The difficulty of destroying the adults makes it important that 
these pests be not allowed to reproduce in a vineyard. The 
1 After this paper had gone to press, in the spring of 1920, the writer's attention was called to extensive 
destructiveness by A. chalybea at Neosho, Mo., by Mr. F. W. Faurot, director of the Missouri State Fruit 
Experiment Station at Mountain Grove, Mo. It was stated that the greater part of the crop in a niamber 
of vineyards had been destroyed by the activities of this beetle during the previous season. In 1920 it was 
apparently much the most destructive grape insect of the region. Spraying experiments for the control 
of beetles emerging from hibernation were conducted by Mr. A. J. Ackerman and the writer, in cooperation 
with the Missouri Fruit Experiment Station. Arsenate of lead at the rate of 3 pounds (powdered) to 50 
gallons of water gave fair control, and this dosage was much more effective than one of 2 pounds to 50 gallons 
of water. 
