158 EXPERIMENT STATION EECORD. [Vol.35 



buds. It was found that healthy ll-year-old trees could be sprayed for three 

 consecutive seasons with miscible oil, 1 : 18, without injury to the trees, and 

 that the scale could be controlled by two seasons' sprayings with this oil. It 

 was further found that combining gasoline emulsion and miscible oil added to 

 the efficiency of the oil. The greatest efficiency was obtained when 5 parts of 

 miscible oil were added to 2 parts of gasoline (emulsified) and 92 parts of 

 water. The third group consisted of ten experiments made with cotton-seed oil 

 and combinations with gasoline. The highest efficiency was obtained by using 

 an emulsion containing cotton-seed oil 5 gal., gasoline 3 gal., soap 2 lbs., and 

 water 92 gal. The fourth group consisting of five experiments made with raw 

 linseed oil gave promising results, the oil being very efficient alone as a 10 per 

 cent emulsion and even more so when combined with gasoline. The gasoline 

 component increases the fluidity of the oil, dissolves the protecting wax film, and 

 tends to asphyxiate the scales. The best results were obtained by using an 

 emulsion made up of raw linseed oil 5 gal., gasoline 3 gal., laundry soap 2 lbs., 

 and water 92 gal. This emulsion applied in the spring before the buds burst 

 will control the terrapin scale at a single application, at a cost for material of 

 from 1 to 8 cts. per tree. This was found to be the most effective treatment of 

 any of the remedies tried against this insect. Group 5, consisting of two experi- 

 ments with mixed oils, showed no advantages in mixing linseed and cotton-seed 

 oils. In group 6 nicotin was tested in 14 experiments, proving this substance to 

 be inefficient. Group 7, consisting of 20 experiments with various coating sprays, 

 gave ineffective results. 



In making recommendations for control the author advises the application of 

 the linseed-gasoline emulsion above mentioned, applied in the spring before the 

 buds burst. In order to protect the crop after the trees are in foliage, it is 

 recommended that an application be made, just before the leafward migration, 

 of the formula consisting of flour (in paste) 10 lbs., stone lime 15 lbs., sulphur 

 20 lbs., and water to make 50 gal. 



A 4-page bibliography is included. 



The alfalfa webworm, C. R. Sanborn {OUalioma Sta. Bui. 109 (1916), pp. 

 S-7, ftijs. 4). — Loxostege similalis, which occurs throughout the United States 

 and in South America, passes the winter in Oklahoma in the pupal stage. The 

 adults emerge from these pupal forms and appear about the middle of April. 

 The second generation appears about May 25, the third from June 28 to July 16, 

 the fourth from July 27 to August 2, the fifth about September 16, and adult 

 forms are present as late as November. The adults deposit eggs in masses, 

 generally on the lower side of the leaves of their food plants, each mass con- 

 tainnig from 5 to 42 eggs, or an average of 19, which hatch ordinarily within 

 three or f(»ur days. The larvjjc or webworms develop in about three weeks, and 

 the pupal period during sununer is ordinarily seven or eight days, but in 

 hibernation extends from about the middle of October to the middle of April. 



All broods, except the last or fall brood, are characterized by their web- 

 .<;pinning habit. While the "careless" or pigweed is its natural food plant, it 

 feeds on practically all the common weeds, except the jimson weed and devil's 

 claw. The methods of control mentioned are mowing infested fields, poison- 

 ing fields, renovation, clean culture, and jarring cultivated plants such as corn 

 and cotton. 



A list <»f 21 references is ajtpended. 



A general survey of the May beetles (Phyllophaga) of Illinois, S. A. Forbes 

 (Illinois Stn. ISul. 186 (1916), pp. 215-251, fig. i).— The data here presented 

 relate to a study of the nunil)er of species and specimens, dates of occurrence, 

 f(.od plants, and distribution in Illinois of nearly 119,000 May beetles or June 



