INSECTICIDES AND EQUIPMENT FOR CONTROLLING ENSECTB 29 



quait of bran) is adequate for treating a garden 50 feet by 50 fee4 

 in size. By broadcasting thinly and evenly, pets and birds will be 

 unable to gather up enough of the material to be poisoned. Any par- 

 ticles of the material which adhere to tender plants should be 

 dislodged to avoid injury. 



On soil which has been in sod or which was weedy the previous 

 season, it is well to apply poisoned bait as insurance against cut- 

 worms, especially before setting out plants or before the plants appear 

 above ground. 



To make a poisoned bait for ants, sowbugs, and millipedes, mix 1 

 part (by volume) of paris green with 9 parts of granulated sugar 

 and sprinkle the bait over the soil. Avoid sprinkling it on tender 

 foliage, otherwise severe burning may result. 



An effective poisoned bait to control mole crickets is prepared by 

 mixing — 



For small For large 



quantities quantities 



Wheat bran 12.5 pounds. 100 pounds. 



Sodium fluosilicate 1 pound. 8 pounds. 



Water to moisten. to moisten. 



Apply at the rate of 20 pounds per acre. 



Caution. — These baits are poisonous and must be stored in la- 

 beled containers so that they will not be used for human or animal 

 consumption. 



Bran is usually available locally at feed stores or mills. Some 

 feed stores sell prepared poisoned baits. 



PYRETHRUM, OR INSECT POWDER 



One of our oldest insecticides and one of the most generally useful 

 is pyrethrum. Pyrethrum pow T der is a plant product and is obtained 

 by grinding the flower buds of the plant Pyrethrum cmerariavfolhnn. 

 a plant wmich belongs to the same botanical family as chrysanthe- 

 mums. The source was originally Persia and Dalmatia, and more 

 recently Japan, but now Kenya Colony, Africa, supplies pyrethrum 

 to this country and our allies. The toxic ingredients of the flowers 

 are the pyrethrins I and II, which together occur in Kenya flowers 

 to an average of about 1.3 percent. In the country of origin the 

 unopened flower buds are harvested, dried, and baled for export. 

 In the United- States the flowers are ground and used for making 

 extracts containing the toxic principles, or are ground fine and used 

 as powder. 



Pyrethrum loses part of its toxic ingredients in a few days when 

 exposed to air and light. Even in airtight metal containers there is 

 some loss of pyrethrins after several months. 



Pyrethrum has several distinct advantages; it is comparatively 

 harmless to higher animals, and in dosage sufficient to kill insects 

 leaves no poisonous residue. It is principally a contact insecticide. 

 and one of its chief disadvantages is the lack of residual effect, i. e.. 

 only insects touched with it are killed. For this reason pyrethrum 

 has not proved satisfactory for use against the most important fruit 

 insects, particularly where the period of attack may extend over 

 several months. 



1 Wartime conditions have led to certain restrictions on the use <>r pyrethrum Insecticides. 

 and these restrictions are subject to change dependent upon tho supply. For up-to-date 



information on tho subject consult the War Food Administration. Office of Materials and 

 Facilities, Washington, D. C. 



