THE IIEMIPTERA 177 



hidden in the grass has destroyed from about 50 to 75 per cent of them 

 in cases where counts of the bugs could be made, including as well, how- 

 ever, areas covered with weeds, fallen leaves and other rubbish. The 

 difficulty with this treatment is to get weather conditions such that the 

 burning can be well done and without injury to the grass. Where 

 thickets, hedges and other excellent hibernating places which cannot be 

 burned out are plenty, this treatment, while of value for the bugs in the 

 areas where this method can be used, will of course fail to reach those in 

 the other locations and thus leave many to appear in the spring. 



Where Chinch Bugs leave one field for another, an old practice 

 has been to plow a furrow across their line of march and dig an occasional 

 hole in the furrow into which the bugs, diverted from their first direction 

 of march, might fall and be destroyed with oil or other material. Bands 

 of tar or of road oil across their line of march have also been used with 

 some success, the difficulty with this plan being in most cases that the 

 band must be placed on firm, hard ground or it will soak in and need 

 frequent renewal, besides forming (with some materials) a surface film 

 on which the bugs can cross. 



Crude creosote similarly applied, has recently been found to work 

 well. Though it soaks into the ground it appears to repel by its odor, 

 and the bugs reaching the band turn away from it. Renewal is necessary 

 only when the odor becomes so slight that it no longer acts as a repellent. 

 In 1914 the average cost for material of maintaining a mile of this band 

 during the migrating period of the bugs was only $16.50 at the then 

 prevailing price of the creosote. 



When the Chinch Bugs are entering fields (usually corn) at this 

 season, spraying the plants with kerosene emulsion. Nicotine sulfate 

 40 per cent and soap solutions has been tested. The former is liable 

 to injure the plants if great care is not given to its application, but the 

 tobacco extracts have proved satisfactory. Soap alone, used at the 

 rate of 3 oz. per gallon of water has given excellent results, and while 

 the Nicotine sulfate, using 3^^ fl. oz. in 1 gal. of water in which ]4, oz. 

 of soap has been dissolved, may be the most effective, soap alone is 

 likely to prove very satisfactory and is less costly. As the bugs enter 

 corn fields from elsewhere, the spray need be applied only to the outer 

 rows if the invasion is observed in time. 



The advice has also been given to cease planting corn in years 

 when the Chinch Bugs are liable to be abundant, raising instead 

 cowpeas, buckwheat, stock beets or soy beans, on which the bugs do 

 not feed. 



In the case of the short-winged form there is little migration, and 

 plowing and the rotation of crops where the insects appear, seems to be 

 about the only treatment available, and probably all that will 

 be necessary. 



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