﻿THE GRAPE LEAFHOPPER IN THE LAKE ERIE VALLEY. 35 



In 1843 J. F. Allen (see Bibliography) advised syringing or spraying 

 infested vines and also smoking them by burning tobacco stalks. 

 Since this date the use of tobacco in both of the forms mentioned has 

 occupied a prominent place among substances recommended for the 

 control of the grape lcafhopper. The former method, that of fumiga- 

 tion, however, was impracticable for the open vineyard. In fact, it 

 is quite probable that the process of fumigation with tobacco was 

 originally intended for use against the insect when found infesting 

 grapevines growing in hothouses which could be closed during the 

 period of treatment. On the other hand, the use of a liquid tobacco 

 decoction has withstood the test of numerous experiments in com- 

 parison with a large number of liquid spray materials and . at the 

 present time is the insecticide most generally recommended in making 

 spray applications against the nymphs. 



In the following paragraphs is presented a list of substances and 

 mechanical methods either experimented with or recommended by 

 various entomologists (see Bibliography) since this insect has been 

 a pest of economic importance: 



Liquid sprays. — Syringing with tobacco water or soapsuds (W. Saunders, 1870). 

 Spraying with carbolic acid (W. L. Devereaux. Rural New Yorker, 1883). Spraying 

 with kerosene and water, or sheep. dip (O. Lugger, 1896). Spraying the adults 

 with kerosene and water and the nymphs with whale-oil soap (M. V. Slingerland, 1904). 



Dust sprays. — Dusting with lime and sulphur (C. J. S. Bethune, 1868). Dusting 

 with hellebore (W. Saunders, 1870). 



Other mechanical methods. — The use of sticky shields to trap the adults; torches to. 

 attract the adults (C. V. Riley, 1873). Destruction of leaves to destroy adults in 

 hibernation (A. J. Cook, 1875). Sticky shields and cloth wet with kerosene to trap 

 adults (J. A. Lintner, 1887). Sheets of cardboard smeared with tar to trap adults 

 (F. M. Webster, 1893). Burning of leaves and rubbish in and surrounding vineyards 

 to destroy adults in hibernation (O. Lugger, 1896). Sticky fans to catch adults as they 

 fly from vines; collecting nets to catch adults (C. W. Woodworth, 1897). Box or cage 

 having inside smeared with a sticky substance ; the cage is placed over the infested 

 vine and the "hoppers" are caught on the sticky sides and bottom of the cage (H. J. 

 Quayle, 1908). Sticky shields held on both sides of the trellis (M. V. Slingerland, 1904). 



Many of the methods of control mentioned in the foregoing para- 

 graphs have been recommended by various other authors treating 

 this subject. The foregoing simply indicate the date 'of their first 

 mention in literature. 



In his experimental work in vine} 7 ards in Chautauqua County, 

 N. Y., Slingerland carried on quite extensive experiments with 

 sticky shields for catching the adults before the commencement of 

 egg deposition, the most practical shield for trellised vineyards being 

 constructed and used as follows: 



Make a light wooden frame about seven or eight feet long and four feet wide, hav- 

 ing the bottom crosspiece about a foot from the ground and fasten to this stiff wires 

 extending down nearly to the ground and bent inward something like hay-rake teeth. 

 Tack over this a strip of table oilcloth \\ yards wide and let it extend down over the 



