20 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 82 



value. Satisfactory traps have been evolved and it seems possible that they will 

 have considerable value in reducing the number of beetles in a given orchard. 

 Bran retains odors over long periods if protected from the rain. Geraniol has 

 been satisfactorily incorporated in poison sprays although its odor is not retained 

 for a long enough period. To this end experiments on the absorption of this 

 chemical on charcoal, clays, etc., are under way. The value of geraniol, when 

 used in connection with a contact spray, has been demonstrated. Eugenol, citral, 

 citronellol and citronellal follow geraniol as attractive agents. 



It is further stated (3) that methods have been devised whereby 

 geraniol may be used to concentrate the beetles in a relatively small 

 area. It was found that by spraying less than an acre of orchard 

 with geraniol, beetles could be drawn on the leeward side of the or- 

 chard for a distance of nearly one-half mile within the first 15 minutes 

 after the spray had been applied. This makes it possible to destroy 

 large numbers of beetles with a comparatively small quantity of a 

 coiitact spray. 



Van Leeuwen and others (87, 90) determined that acetic acid, an 

 accumulation of beetles, geraniol, and fermented apple juice attract 

 these beetles. It was discovered that the beetles would gorge them- 

 selves upon foliage sprayed with a mixture of lead arsenate and re- 

 fined sugar, on trees to which they had been attracted by geraniol 

 (pi. I, B). More beetles fed on this foliage than on unsprayed leaves, 

 and consequently the mortality was greater than ever before obtained. 

 Smith (78) more recently reports that a combination of lead arsenate 

 and refined cane-sugar sirup has been found useful as a spray on non- 

 economic plants. The beetles are strongly attracted to it and eat it 

 readily. He says that this preparation is probably one of the most 

 efifective lethal sprays yet devised for the Japanese beetle. Owing to 

 its tendency to injure foliage it is not recommended for use on 

 economic plants. 



Metzger (52) and Richmond and Metzger (68) describe various 

 types of traps, one being called the standard bait trap. Each kilo- 

 gram of the standard bait contains 500 grams of bran, 455 grams 

 (350 cc.) of molasses (refiners' sirup 75 per cent), 44 grams (40 cc.) 

 of glycerine, and a quantity of an attractant. With geraniol as the 

 attractant making 5 per cent of the prepared bait, the bran-glycerine- 

 molasses mixture does not deteriorate to any marked degree when 

 exposed to the weather, and its attractive odor has been retained more 

 than three years in some traps. In practice, baits were renewed twice 

 a month, 150 grams of the prepared bait being put in each trap. The 

 best bait, however, was found to be a technical geraniol, 58.8 per cent 

 pure, used in the proportion of 2.5 per cent with eugenol in the pro- 

 portion of 0.25 per cent of the total material. The total number of 



