30 GRASSHOPPERS AND OTHER INJURIOUS INSECTS OF 1911 AND 1912. 



five rods or so — with Arsenite of Sodium and leave this uncut as a "bait 

 strip." After acting as above, Mr. Marks examined the corn field and reported 

 that he saw numei'ous dead hoppers "even as far as five rods into the corn 

 from the spray," and in the poisoned strip he noted many dead and many 

 "sick." 



While in some cases we found that the spray at the strength given above 

 had a tendency to burn the tips of the leaves somewhat, this was neither 

 general nor serious, and in all cases the grain had normal color a week or so 

 later even though apparently somewhat burned immediately after spraying. 

 We found however that young grain is far less sensitive, and wheat, oats and 

 barley when sprayed when four or five inches high showed no effect even 

 when the spray was used at one-half stronger than the above formula. 



It was found in the experiments that certain plants, notably "Wild 

 Mustard" and "Wild Buckwheat" were badly "burned" by the spray even 

 when the grain was entirely unafl'ected thus there may be somewhat of a 

 secondary value to the use of this spray. 



The question in the minds of the farmers before applying this poison is 

 whether it will kill or seriously afi^ect his stock, should they get into the field 

 so sprayed. No one expects to place his stock upon a steady diet of this 

 poisoned grain for a long period but he wishes to be sure that should the 

 stock get to the sprayed field for a time, they will not be injured. We feel 

 no hesitation in saying that fi'om the amount of poison shown upon the grain 

 by actual analysis and from tests made by the State Entomologist, and quoted 

 above, stock would be liable to no injury unless fed solely upon this poisoned 

 material and even then, unless the feeding was continued for some days. It 

 is of course evident that no such long continued feeding could occur unless 

 purposely carried out as a test. It should always be remembered however in 

 using this poison or any other poison that is strong enough to be of value, that 

 reasonable care and intelligence is imperative in handling such materials. 



Among other poisons which have been used with good eff'ect against grass- 

 hoppers is the well known "Criddle ^Mixture" which is merely a mixture of 

 Paris Green and horse manure — usually the proportion of one part of Paris 

 Green to about one hundred parts by measure. The Paris Green is stirred into 

 a quantity of water and then this aqueous mixture is stirred into the manure, 

 adding enough more water to make the mixture of about the consistency of 

 bran mash. This is an excellent means of killing grasshoppers but owing to 

 the large amount of hoi'se manure required to poison large areas, it is more 

 feasible to use this in small tracts like garden patches. The mixture is simply 

 scattered throughout the garden by means of a paddle. The mixture as nor- 

 mally used is not poisonous to jioultry, although it might be harmful to young- 

 chicks. 



Another device similar and no more efficient is a mixture of bran, Paris 

 Green and water — usually about two parts of Paris Green to about twenty-five 

 parts of bran. In some cases this mixture is sweetened by adding syrup or 

 molasses. Care must be taken not to place this mixture whei'e it will touch the 

 plants. 



Since we found the Arsenite of Sodium so satisfactory in our spray tests 

 it was tried in a mixture somewhat similar to the Criddle described above and 

 tests show the new mixture to be in some ways better than the former and 

 certainly considerably less expensive. The best formula for this mixture so 

 far as we have tested it is as follows: Sodium Arsenite one pound, horse 

 manure one hundred and twenty to one hundred and fifty pounds, molasses 

 (any cheap grade) one pint. Dissolve the arsenite in water and then add to 

 the manure, stirring well. The mixture, which may perhaps be called the 

 "Minnesota Mixture," may be used exactly as the "Criddle," but owing to the 

 cheaper poison used and to the fact that so much poison is not required we 

 have found it more economical. Its attractiveness as a bait is fully as notice- 

 able as with "Criddle" and in fact we feel that the addition of molasses has 

 improved the value as a bait. In oi'der to test its effect on poultry we fed two 

 roosters upon the mixture for some time with no bad effects. We tried also 

 the effect of corn boiled in strong solutions of the Sodium Arsenite and by 

 careful tests found that nearly one-half a gram of the poison was required 



