BAITS FOR SCREW-WORMS AND BLOWFLIES UNDER RANGE CONDITIONS
Where rabbits or other wild animals are plentiful they make a very satisfactory bait for use on the ranges; in fact, they are rather better than any other available bait. The animal should be opened up so as to expose the intestines; and when the weather is very dry it is best to keep some water in the pan, as it adds to the attractiveness of the bait. Entrails and other animal refuse may be utilized in a similar way when they are available. In large trapping operations goats or sheep culled from the flock are cut up for bait, from 1 to 2 pounds of meat being used in each bait pan.
The main objection to the use of these meat baits is that some maggots are likely to complete their growth and escape from the bait pans. This can be largely avoided by adding nicotine sulphate to the water in the bait pan in the proportion of one teaspoonful to each gallon of water. This does not check the decomposition enough to reduce the attractiveness of the bait and practically prohibits the escape of any maggots.
As a substitute for wild animals or animal refuse when they are not available, experiments show that fairly satisfactory catches can be secured by utilizing dried "gut slime" or dried whole egg. The former is not generally on the market but can be prepared by packing houses at a moderate cost. Both of these materials are easily carried on a saddle horse, and all that is necessary is to place about one-fourth pound in the bait pan and add 1 gallon of water, after which the mixture should be stirred. The more frequently any of these baits is agitated, the greater the catch which will be secured. If the bait is kept well moistened it will continue attractive for 10 days or longer. These baits should be kept alkaline by the addition, once or twice a week, of a teaspoonful of washing or baking soda.
COMBINATION BAITS
With a number of the baits before mentioned both house flies and blowflies are captured. This is especially true with the "gut slime" and dried egg. Where both of these kinds of flies are abundant such baits are desirable. Certain other mixtures may also be utilized. A packing-house product known as blood tankage is a good fly bait when used before drying and with molasses and water. Fish scraps or meat scraps, especially with molasses and water added, will attract all kinds of flies. Overripe or fermenting fruit such as watermelon rinds or crushed bananas often gives very satisfactory results. A combination of overripe bananas with milk is much more attractive than either one used separately.
[BAIT CONTAINERS]
The size of the bait container in relation to the size of the trap is a very important consideration. It has been found that a small pan or a deep pan of bait set in the center under a trap will catch only a small fraction of the number of flies secured by using larger shallow containers. The best and most convenient pan for baits is a shallow circular tin, such as the cover of a lard bucket. Under range conditions it is advisable to use a more substantial bait pan and preferably one 4 inches deep, so that a greater quantity of bait may be used, thus preventing complete drying out between visits to the trap. Its diameter should be about 4 inches less than that of the base of the trap, thus bringing the edge within 2 inches of the outside edge of the trap. For liquid baits the catch can be increased slightly by placing a piece of sponge or a few chips in the center of the bait pan to provide additional surface upon which the flies may alight.
[CARE AND LOCATION OF TRAPS]
In many cases flytrapping has been rendered ineffectual by the fact that the traps were not properly placed or cared for. In setting traps a location should be chosen where flies naturally congregate. This is usually on the sunny side of a building out of the wind. In hot weather, however, traps should be placed so as to be in shade during midday. It is exceedingly important that the bait containers be kept well filled. This usually requires attention every other day. The bait pans should be washed out at rather frequent intervals. This gives a larger catch and avoids the danger of flies breeding in the material used for bait. Further, it should be borne in mind that traps can not be operated successfully throughout the season without emptying them. Where flies are abundant and the bait pans are properly attended to the traps should be emptied at weekly intervals. Where flies become piled high against the side of the cone, the catching power of the trap is considerably reduced. The destruction of the flies is best accomplished by immersing the trap in hot water or, still better, where a tight barrel is at hand place a few live coals in a pan on the ground, scatter two tablespoonfuls of sulphur over them, place the trap over the coals, and turn the barrel over the trap. All of the flies will be rendered motionless in about five minutes. They may then be killed by using hot water, throwing them into a fire, or burying them. In the operation of flytraps in controlling the screw-worm it has not been found necessary, especially during hot weather, to kill the flies, as they die very rapidly within the traps. In order to empty a trap it may be inverted and the dead flies shaken down. As the living flies will naturally go upward, the door may then be removed and the dead flies shaken out, the door replaced, and the trap set upright without loss of many of the living flies. The location of traps used against the screw-worm fly is briefly discussed on [page 11].
[STICKY FLY PAPERS]
Sticky fly papers are of some value in destroying flies which have gained access to houses, but they have marked limitations and numerous objectionable features. For use out of doors traps are much more effective and economical.
Doctor Crumbine, of the Kansas State Board of Health, gives the following method for preparing fly paper:
"Take 2 pounds of rosin and 1 pint of castor oil; heat together until it looks like molasses. Take an ordinary paintbrush and smear while hot on any kind of paper—an old newspaper is good—and place several about the room. A dozen of these may be made at a cost of 1 cent."
Transcriber Note
Minor typos have been corrected. Illustrations were moved to prevent splitting paragraphs. Produced from files generously made available by USDA through The Internet Archive. All resultant materials are placed in the Public Domain.