THE GROUND SQUIRRELS OF CALIFORNIA. 



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teaspoonful of saccharin has been added. When the solution is cool as many trimmed 

 barley heads should be put into it as the liquid will cover and they should be allowed 

 to soak for twenty-four hours. The poisoned heads should be distributed in the early 

 morning so that they may be eaten before drying. Two or three should be placed 

 near each hole inhabited by adult squirrels and six to eight in the case of families 

 of young as each squirrel is likely to eat an entire head before the poison takes effect. 



Caution — Care should be taken in distributing in places accessible to stock, 

 particularly if feed is scarce. 



Poisoning Fresh Fruits, Etc. Strychnin sulphate is freely soluble in fruit juices 

 and these seem to conceal, to some degree at least, the bitterness of the strychnin. 

 Cull fruits of various kinds have been used successfully. Oranges cut in halves, 

 watermelon rinds cut into pieces about three inches square and poisoned by sprinkling 

 with powdered strychnin sulphate make excellent baits. It seems to be the moisture 

 contained in these baits that makes them particularly acceptable during the exces- 

 sively dry season. Powdered strychnin inserted into prunes and raisins by means 

 of a knife blade is very effective. 



Carbon Disulphid. Carbon disulphid is one of the best agents to be used as a 

 follow-up method to get the squirrels that fail to take poisoned grain. It should 

 only be used when the soil is sufficiently wet to keep the gas from escaping. 



Method of Application. Balls made of cotton waste, old sacking or other absorptive 

 material should be made large enough to hold at least two ounces of the fluid when 

 saturated. Ready-made balls can be purchased from firms selling carbon disulphid. 

 A number of these balls are placed in a covered pail to prevent the gas from escaping 

 and over these is poured sufficient carbon disulphid to cover entirely after saturation. 



To Load the Burrows the saturated balls are taken from the pail by means of a 

 wire hook and placed into the burrows as far down as possible. It is well to load 

 all holes in a colony before exploding. This will overcome the danger of being burned 

 when loading a communicating burrow. The explosion of the gas is recommended 

 because vaporization under normal conditions would not occur so quickly. 



When the gas in the burrow is exploded a chemical reaction takes place which 

 produces a volume of gas three times that of the carbon disulphid itself. The 

 gases produced in addition to carbon dioxide are carbon monoxide and sulphur 

 clioxid which are in themselves quite poisonous. The explosion forces these gases 

 to the farthest recesses of the burrow. After exploding, the mouth of the burrow 

 should be stopped up with a clump of earth or sod well mounded and tamped. 



FORMULA 1 FOR POISONING CALIFORNIA DIGGER GROUND SQUIRRELS. 



Whole barley (recleaned grain) 1 sack or SO quarts 



Strychnin (powdered alkaloid) 5 ounces 



Baking soda (bicarbonate of soda) 5 ounces 



Heavy corn syrup 1 pint 



Thin starch paste 3 pints 



Saccharin 1 ounce 



Pure glycerin 5 tablespoons 



1 Quantities for a one-sack mixing. 



Mix the strychnin, soda, and saccharin together and crush all lumps with the 

 mixing spoon. Add the corn sirup and stir to a smooth creamy paste. Add the 

 starch solution and stir well to free all of the sirup paste that may have adhered to 

 the bottom of the container. Lastly add the glycerin. The above mixing ought to 

 be done in a vessel no smaller than a small dishpan. 



Pour the mixture over the amount of grain called for and mix thoroughly until 

 every grain is coated. If mixed in a large box, with shovels, the batch should be 

 turned back and forth at least 8 times. 



FORMULA 1 FOR POISONING "CALIFORNIA DIGGER GROUND SQUIRREL." 



Whole barley (recleaned) 320 quarts or 80 gallons 



Strychnin (powdered alkaloid) 20 ounces 



Bicarbonate of soda (baking soda) 20 ounces 



Heavy corn sirup 2 quarts 



Starch paste (medium consistency) — 3 quarts 



Glycerin 20 tablespoons 



Saccharin , r 2 ounces 



% J?or large mixings, 4 sacks. 



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