HANDBOOK OX INSECT ENEMIES OF FLOWERS AXD SHRUBS 97 



Fluorine Compounds 



Fluorine compounds have limited use 

 as substitutes for arsenicals in the con- 

 trol of flower-garden insects, especially 

 certain beetles and weevils. Cryolite 

 (sodium fluoaluminate') in both the 

 natural and the synthetic forms, is used 

 against blister beetles, flea beetles. 

 Fuller's rose beetle, and the imported 

 cabbageworm. For spraying, it is used 

 at the rate of 2 to 3 pounds in 50 gal- 

 lons of water. In small quantities use 

 2 3 to 1 ounce, or 5 to 8 level teaspoon- 

 fuls. to 1 gallon of water. For ducting. 

 2 parts of cryolite is mixed with 1 part 

 of tobacco dust. clay. talc, pyrophyllite. 

 sulfur, or cheap flour. Lime should 

 not be used as a diluent for the fluorine 

 compounds. 



Barium fluosilicate and sodium fluo- 

 silicate are other fluorine compounds. 

 The former is used in the same manner 

 a- cryolite. Sodium fluosilicate, how- 

 ever, is more likely to burn the plants 

 unless used in very dilute form, con- 

 sequently it has more limited use. It 

 is chiefly used as a poison in cutworm, 

 mole, cricket, or gasshopper baits. 



Caution. — All fluorine compounds 

 are poisonous and should be handled 

 with care and kept away from food. 



Bordeaux Mixture 



Bordeaux mixture is chiefly used as a 

 fungicide for controlling certain fungus 

 diseases. It is also employed, however 

 as a repellent against attack by flea 

 beetles, the potato leafhopper, plant 

 bugs, and a few other pests, and as an 

 emulsifying agent for oil sprays. 



Home-made bordeaux mixture may 

 readily be prepared with the following 

 ingredients: 



For small For large 



quantities quantities 



Bluestone ( copper sulfate).. 4 ounces. 2 pounds. 



Hydrated lime 6 ounces. 3 pounds. 



Water 3 gallons. 25 pounds. 



Dissolve the bluestone crystals in hot 

 water in a wooden, earthenware, or glass 

 vessel (never in metal). Dilute with 

 half the total water specified. Then 

 make a paste of the lime in a small quan- 

 tity of water, and add the rest of the 

 water to this. Next pour the diluted 

 bluestone and lime solution together 

 and mix thoroughly. Finally, strain the 

 mixture through fine cheesecloth di- 

 rectly into the sprayer. This mixture 

 should be made fresh each time it is 

 used. 



Manufactured products, both pastes 

 and powders, are also available for 

 making up bordeaux mixture. They 



are especially convenient for use in small 

 gardens and are satisfactory under most 

 conditions of moderate infection. The 

 manufacturer's directions should be 

 followed in preparing and applying this 

 material. 



Lead arsenate, calcium arsenate, and 

 nicotine sulfate may be combined with 

 the prepared bordeaux mixture. 



Caution. — Bordeaux mixture may 

 cause gastric disturbances if taken in- 

 ternally. All unused portions should be 

 disposed of or covered so that they will 

 be inaccessible to children and animals. 

 It is also somewhat irritative to the eyes 

 and skin. 



CONTACT INSECTICIDES 



Nicotine Sulfate as a Spray 



Nicotine, in various forms, is one of 

 the most generally used of the standard 

 contact sprays because of its effective- 

 ness and the ease with which a spray 

 can be prepared. It is used against 

 many sucking and other soft-bodied 

 insects. Besides being available in the 

 form of tobacco extracts, it can be pur- 

 chased under a number of proprietary 

 names as a liquid containing nicotine 

 sulfate or nicotine itself. Both these 

 liquids, as commercially sold, contain 

 not less than the equivalent of 40 per- 

 cent of nicotine by weight. Since the 

 concentrations of the commercial prod- 

 ucts vary, the directions for their dilu- 

 tion, which are usually given on the 

 labels of the containers, should be fol- 

 lowed. Concentrates containing 40 per- 

 cent of nicotine sulfate should be diluted 

 with soapy water as follows: 



For small quantities. 1 to \\i teaspoonfuls to 1 

 gallon of water. 



For larger quantities. 1 fluid ounce to 8 gallons of 

 water. 



For more resistant insects it may be 

 necessary to use a little more of the 

 nicotine sulfate. 



The solution is prepared by dissolving 

 about 2 rounded tablespoonfuls of soap 

 flakes, or the shavings of a 1-inch cube 

 of some hard but cheap soap, in each 

 gallon of water and adding the nicotine 

 sulfate immediately before spraying. 

 If the prepared spray has stood for some 

 time, it should be mixed thoroughly 

 before being used. For plants with a 

 waxy or glossy surface it may be neces- 

 sary to add more soap. This is easily 

 determined by looking at the freshly 

 sprayed plant*. If the spray draws to- 

 gether in drops, more soap is needed. 

 Fish-oil soap or some of the newer wet- 

 ting agents (p. 103) may be substituted 

 for the laundry soap. The insects must 



