A BOX-TYPE TEAP FOE EYE GXATS AXD BLOWFLIES 6 



CARCASS AND GARBAGE DISPOSAL TRAP 



The carcass and garbage disposal trap is essentially the same as the other 

 blowfly trap described except that it is larger, being 6 feet wide, 12 feet long, 

 and 18 feet high, and has a concrete base and septic tank or cesspool con- 

 nected with it, and should have an incinerator. The concrete approach is for 

 sanitary purposes only. The concrete base for the trap is 6 inches deep and the 

 side walls are 18 inches deep. The entrance boards are made to swing up, 

 so that a truck can be backed into the trap and unloaded. A small side door 

 is provided through which to dump small animals or garbage in small quantities. 



COST OF TRAPS 



The cost of traps will differ widely according to size, prices of materials 

 in different localities, the quality of materials used, and the price of labor for 

 construction. The blowfly trap described in the mimeographed circular men- 

 tioned above required 176 board feet of Xo. 1 common pine lumber, 81 square 

 feet of 12 and 14 mesh galvanized screen, and hardware. The total cost of 

 materials was $10.31 at Uvalde, Tex. ; carpenter work required was eight hours, 

 at $1 per hour ; a blacksmith furnished the materials and made the bait agita- 

 tor for $3; and the total cost amounted to $21.31. The cost of applying two 

 coats of paint could not be definitely established. A trap of the same size 

 was constructed on a ranch by two carpenters in three and one-half hours ; 

 they used lumber taken from a building that was being remodeled. The trap 

 has been in use two seasons, and has frequently been moved about over the 

 ranch. It is still in first-class condition and has been very satisfactory to 

 the owner. 



The eye-gnat traps require much more labor than the fly traps, and must 

 be of high-class workmanship to be satisfactory. For this reason they are 

 rather expensive. The materials must be of a grade that can be worked into 

 very close fitting joints and all joints must be thoroughly puttied and painted. 

 The labor required on the trap illustrated in Figure 1, B, was 42.5 hours : the 

 materials cost $29.73 ; and the bait agitator cost $3.40. The total cost of the 

 trap at Coachella. Calif., was $75.63. 



The cost of each item of the carcass and garbage disposal trap is not known, 

 but the total cost of the trap, septic tank, and connections was approximatelv 

 $153 at Menard, Tex. 



LOCATING AND BAITING TRAPS 



The traps are intended to attract insects from a considerable distance and 

 for this reason they should not be located in such situations as closed coves 

 or canyons, places surrounded by high thick hedges, or buildings, or close 

 beside such hedges or buildings. Neither should they be exposed to high 

 winds. The most suitable locations are in open groves or thin plantings of 

 trees or shrubs, such as vineyards, young citrus orchards, date-palm plant- 

 ings, and on range having a moderate low growth or open high timber. The 

 traps must always be set so that one of the two entrances will face away from 

 the prevailing winds and never sidewise to these winds. 



The blowfly traps are intended to be used in conjunction with other remedial 

 measures in the control of the screw-worm flies on ranges. They were designed 

 to accommodate a larger bait than other traps commonly used, in order that 

 whole carcasses of animals could be utilized without the disagreeable task of 

 cutting them into small baits. The trap illustrated in Figure 1,. A, will ac- 

 commodate carcasses of sheep, goats, coyotes, small calves, and other animals 

 up to a maximum weight of 100 pounds. The large concrete-base trap will 

 utilize all sizes of carcasses up to a total weight of about 3,000 pounds or to 

 total contents of 200 cubic feet. The best catches of flies are made when the 

 baits are partly or wholly covered with water ; and where enough water is 

 used to float the baits, the windmill bait agitator has proved advantageous. 

 When water is used it has generally been found advantageous to add, as a 

 larvicide, a tea spoonful of nicotine sulphate per gallon of water. This must 

 not be done if the trap is to be used to breed a continuous supply of parasites 

 of the larvae and pupae of flies. 



The bait for the eye-gnat trap described has usually been 1 pound of beef or 

 hog liver and 2 ounces of urea to 4 gallons of water. From 20 to 30 gallons of 



