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MISC. PUBLICATION 62 6, IT. S. DEPT. OF AGRICULTURE 



be wetted bv the spray or thev will not 

 be killed. 



Nicotine sulfate may be safely com- 

 bined with most other insecticides. 



Caution. — Nicotine and its com- 

 pounds are violent poisons, and care 

 should be exercised in their use. Ex- 

 posure to fumes or sprays for any length 

 of time causes acute nausea in some 

 persons. Combinations other than nico- 

 tine bentonite are most likely to give 

 this effect. Susceptible persons should 

 protect themselves with a respirator 

 provided with pads saturated with a 

 solution of citric acid. 



Acute illness can be caused by the 

 absorption of nicotine through the skin. 

 If concentrated solutions of nicotine are 

 spilled on the skin, they should be im- 

 mediately washed off with water. The 

 operator should not continue working 

 in outer clothing which has become wet 

 with nicotine-containing sprays, as the 

 body will take up the nicotine from the 

 clothing. 



Nicotine Sulfate as a Dust 



Nicotine sulfate combined with a 

 dry carrier makes a dust which is useful 

 whenever it is preferable to apply a 

 dust rather than a spray. It can be 

 obtained as a commercially prepared 

 product ready to apply to the plants. 

 For home use, it may be prepared 

 by adding the required proportion of 

 nicotine sulfate to hydrated lime. 

 These dusts are generally used for the 

 control of aphids and other soft-bodied 

 insects, where the temporary whitish 

 deposit on the plants is not objection- 

 able. Strengths varying from 2 to 4 

 percent of actual nicotine are generally 

 used, depending on the resistance of the 

 insects. 



To make a dust containing approxi- 

 mately 2 percent of nicotine (allowing 

 for a slight loss by evaporation), the 

 following formula may be used: 



Nicotine sulfate, 1 to 1H ounces, or 5 to 8 tea- 

 spoonfuls. 

 Hydrated lime, 1 pound. 



For more resistant insects the pro- 

 portion of nicotine sulfate should be 

 doubled to make a 4-percent nicotine 

 dust. 



The mixture may be prepared by 

 pouring the nicotine sulfate over the 

 dust and then passing it through an 

 ordinary household flour sifter. Be 

 sure that all lumps are broken up and 

 passed through the sifter. Resift at 

 least three times to insure a thorough 

 mixture. Or, place a quart of fresh 



hydrated lime in a container which can 

 be tightly closed, add a handful of 

 small stones or marbles, pour in 1 fluid 

 ounce of nicotine sulfate, close the lid, 

 and shake well for several minutes. 

 Remove the stones by passing the mix- 

 ture through a sifter or screen. Larger 

 quantities may be prepared by placing 

 the lime and nicotine sulfate in a keg 

 or metal drum with a tight-fitting 

 cover, together with several sizable 

 stones or pebbles, and then rolling the 

 drum for about 20 minutes to insure 

 thorough mixing. 



A single application is often successful, 

 but the treatment may be repeated as 

 often as is required. It is best to use 

 the dust promptly, otherwise it should 

 be stored in tight metal or glass con- 

 tainers, as it loses its strength rapidly 

 when exposed to the air. The dust 

 should be applied by means of a hand 

 duster, and the application should 

 preferably be made when the tempera- 

 ture is about 65° F., the foliage dry, and 

 the air still. 



Caution. — In mixing and applying 

 the dust the operator should be careful 

 to avoid inhaling much of it, for it may 

 cause irritation in the nose and throat. 

 See also caution on this page. 



Pyrethrum 



Pyrethrum is a contact insecticide 

 that may be safely used as a spray or 

 dust in the flower garden. It is effective 

 against such sucking insects as aphids, 

 thrips, plant bugs, and leafhoppers. It 

 is also effective against certain chewing 

 insects, including the caterpillars and 

 adults of leaf tiers or leaf rollers, and 

 the adults of the Japanese beetle, black 

 blister beetle, Fuller's rose beetle, rose 

 chafer, cucumber beetles, and probably 

 others. The insecticide must come in 

 contact with the body of the insect. 



Pyrethrum powder is made from the 

 flower heads of several species of Chrysan- 

 themum. The active ingredients or insect 

 poisons are two oily substances known 

 as pyrethrin I and pyrethrin II. The 

 strength of a spray or dust, therefore, 

 depends on the percentage of total 

 pyrethrins contained in the final mix- 

 tures. For spraying garden plants the 

 liquid alcoholic extract, containing about 

 2 to 3 percent of pyrethrins, and diluted 

 according to the manufacturer's direc- 

 | tions, is preferable. For dusting, the 

 i pure, fresh pyrethrum powder, con- 

 taining approximately 1.3 percent of 

 pyrethrins may be diluted with 3 parts 

 , of such nonalkaline material as tobacco 



