D CIRCULAR 51, U. S. DEPARTMENT OE AGRICULTURE 



householder are the common laundry soaps. These soaps applied at 

 the rate of 1 pound to 5 gallons of water, or a tobacco solution con- 

 taining 40 per cent nicotine, used at the rate of 1 part to 800 parts 

 of water, with 1 pound of soap to 25 gallons of the mixture, will 

 effect complete control if properly applied. These solutions, how- 

 ever, have no effect upon the eggs of the chinch bug. 



It is important that applications of insecticides be made when the^ 

 first sign of injury is noted. As plants which are yellowing, and™ 

 probably the near-by plants, are the ones upon which the bugs are 

 most numerous, these should be very thoroughly treated. Insecti- 

 cides applied to the dead brown grass are largely wasted, as the 

 insects have already left this in search of more attractive food. 

 Usually a strip from 3 to 5 feet wide about the edge of an infested 

 spot contains a large majority of the chinch bugs present, but careful 

 examination of the grass should determine the extent of the surface 

 to be treated. 



Insecticides can be applied with some type of sprayer or with a 

 common garden sprinkling can. The principal emphasis should be 

 placed on the thoroughness of the application, the best method being 

 simply to deluge the plants, since the bugs crawl quickly into trash 

 and loose soil for shelter. The best success has been obtained where 

 the insecticides were applied immediately after a rain or after the 

 affected ground had been well irrigated. One thorough treatment 

 will usually control an outbreak on any particular patch of ground, 

 but another application may be necessary two weeks later if a large 

 number of eggs have hatched. 



A control measure which the Florida Agricultural Experiment 

 Station 2 recommends is the use of calcium cyanide. In applying 

 this, certain precautions must be taken to prevent burning the grass. 

 The insecticide should be applied in the middle of a clear day after 

 evaporation of dew and when there is no immediate likelihood of 

 rain, as it is necessary that the grass remain perfectly dry until the 

 cyanide has dissipated its strength. The cyanide should be applied 

 very evenly, after which it would be desirable to sweep the grass 

 immediately with an old broom so as to brush the insecticide off the 

 green blades down into the mat of dead leaves and stems, in which 

 the insects are present near the ground. This prevents burning the 

 foliage and also places the insecticide in direct contact with the 

 insects. Great caution should be exercised in using the cyanide, 

 as it is a violent poison. Those working with it should keep to 

 the windward of its dust, and the container should be opened only 

 where there is good ventilation. 



CULTURAL METHODS 



St. Augustine grass should be kept in a thrifty condition, by irri-A 

 gation and fertilization if necessary, so that its increased vitality" 

 will enable it better to withstand chinch-bug injury. Kesistance or 

 the grass to injury is increased, also, when the grass is not mowed 

 too closely during dry weather, and where attacks are imminent 

 mowing should be delayed. 



2 Watson. J. R. the chinch bug on st. augustine grass lawns. Fla. Agr. Expt. 

 Sta. Press Bui. 371, [2] p. 1925. 



