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(1) Fungicide only-self-boiled lime-sulphur, June 9 and July 14. (2) Self-boiled lime-sulphur plus lead arsenate, plus nicotine sulphate,
plus casein lime, June 9 and July 14; nicotine sulphate plus soap,
June 30, July 28 and August 15. (3) Self-boiled lime-sulphur plus lead arsenate, June 9 and July 14. (4) Sulphur arsenate dust followed by nicotine dust, June 9 and July
14; nicotine dust, June 30, July 15 and August 2. Counts were made of all drop fruits from 10 selected trees in the center of each block and of all fruit from five selected trees in each block, the scoring being done by exterior examination, grading into infested and uninfested lots. A number of each of these lots were then cut open and the correction for infested peaches overlooked in the first grading, applied to those figures. The results are seen in Table 3.
No conclusions will be drawn from these experiments until checked by similar tests, but they are presented here in order to show what was obtained in the way of control measures in 1924.
ORIENTAL PEACH MOTH CONTROL—1924.
Block No. 1
TABLE 1-PICKED FRUIT FROM FIVE SELECTED TREES.
10.8 5 sprays containing nicotine sulphate 2 with lead arsenate 2,528
6.9 Fungicide plus lead arsenate
10.3 5 dusts containing nicotine, 2 with arsenate
1 2 3 4
TABLE 2-ALL FRUIT FROM FIVE SELECTED TREES.
7.8 12.1 6.0
TABLE 3—CORRECTED FIGURES FROM TABLE 1 BASED ON Cut FRUIT. 1
TABLE 4-TWIG COUNTS OF ALL TREES MADE JULY 28, 1924. Block
Injured Twigs Twigs per Tree 1
EFFECT OF VARIOUS INSECTICIDES ON THE EGGS OF THE EUROPEAN RED MITE (P. pilosus C. & F.)
PHILIP GARMAN. Since the publication of Bulletin 252, on the European red mite, a number of tests have been made of the killing power of certain insecticides on the winter eggs. These tests are laboratory tests and results are comparable to what was obtained in previous experiments. For convenience, two proprietary oils now on the market have been compared and the results are shown in Table 2. Results in this table are a total of all tests made to date, including those reported in Bulletin 252.
Total No. of
Hatched Materials Used
Number Per Cent, 1. Niagara dormant dust.
19 15.9 2. Soluble sulphur 1 oz. in 1 quart
29 25.2 3.
32 16.1 4.
98 20.5 5.
99 43.0 6.
49 24.3 7. Sunoco spray oil 1-15.
.4 8. 1-15.
3.7 9. 1-15
.5 10. 1-20.
227 11. Carboleine 1-15..
1.0 12. 1-20..
.6 13. Volcks 3%
1.9 15. Sherwin Williams Free Mulsion 1-15 202
1.9 16. Check--no treatment....
225 46.5 Note. Tests 2-5 were made with fresh soluble sulphur of good yellow color; No. 6 with the same material after standing a year.
The percentage of hatch in the two lots should not necessarily be taken to indicate superiority of either oil, since the experimental error and variation is considerable. The experiments, however, indicate consistently that a dilution of 1 to 20 or 1 to 25 does not greatly reduce the toxicity of miscible oils of this type. As indicated in Table 1, soluble sulphur compounds do not give
as high a mortality in laboratory tests, although they have in common with oils, the property of covering all parts of the twig and "crawling" into spots not actually reached by the spray.
Some criticism of Table 14, Bulletin 252, has been received from manufacturers. Owing to omission of results in Table 11 from the final summary, Sunoco Spraying Oil was placed at the bottom of the list. Revised from the data as summarized in Table 14 from previous records in Bulletin 252, the last five items should read. Exp.
Hatched Possible Kill Number
Per Cent. Eggs Used 10 Wormol...
711 11 Scalecide..
8,154 12 Sunoco Spray Oil..
968 14 Jarvis Compound.
896 The original idea of this table was not to indicate superiority of any particular product especially where percentages are close, since the conditions of experiment varied, but was intended to show the increased kill in the case of certain types of miscible oils over other ovicides, namely lime-sulphur compounds or substitutes. However, in view of the possible harm done to certain manufacturers of spray materials we take pleasure in revising the latter part of this table and presenting it in corrected form. The figures represent a summary of all tests made with different dilutions and obviously should not be used as a direct comparison of different products.
THE ALCOHOL-FORMALIN SOLUTION FOR CONTROL
OF AMERICAN FOUL BROOD.
Dr. J. C. Hutzelman was the first to demonstrate that combs containing American foul brood may be successfully sterilized with a mixture of formalin and alcohol. For this purpose he used a solution of 20 per cent. formalin in alcohol, soaking the combs 48 hours after extracting all honey. He reports the successful sterilization of many combs. These facts together with the recommendation of this treatment by one of the largest manufacturers of bee supplies makes it advisable to explain the methods more fully, examining the constituents of the solution in detail in order to know what may be expected of it.
The procedure in general* is as follows.-Infected hives are removed to a "hospital yard" away from the main apiary, the bees shaken, hives disinfected and the combs treated according to the following method. The cells are uncapped, honey extracted and the combs are then placed in warm water which is later thrown out in the extractor. This treatment is necessary in order to remove all traces of honey which might remain in the combs and interfere with the disinfection. The combs are then placed in the alcohol-formalin solution and allowed to remain 48 hours after which the formalin solution is extracted and the combs allowed to dry. After these operations are complete, the bees are given a new queen and returned to the disinfected hive and combs.
1 See references at the end of this article.
Some workers state that it is not necessary to uncap all cells before immersion in the solution, but the advisability or inadvisability of this method has not been fully demonstrated. Knowing, however, the nature of the disease, that is, its bacterial origin, and the difficulty in getting rid of such diseases, it seems necessary to omit no precautions and to exercise the greatest care in treating the combs, It is known, moreover, that spores of American foul brood may remain without germination for many years and the inadvisability of basing conclusions on one season's work seems undesirable, unless of course the disease reappears within that time.
The minimum amount of the solution required is not less than five gallons and for practical purposes not less than 10 gallons should be purchased. For larger amounts special tanks should be constructed and special equipment obtained"The material may be used repeatedly according to the manufacturer's recommendations.
Alcohol-formalin solution is very irritating and troublesome to handle. The fumes given off are stifling especially if confined to a closed room. We therefore recommend that it be handled in the open or in a place where there is plenty of ventilation. If the contents of each comb after soaking in the solution, are shaken back into the treating tank, fumes will be produced which will cause much discomfort to the operator. It is best to place the combs in the extractor direct, cover same and extract under cover; and it is especially desirable to handle the combs being treated with rubber gloves or some tool which will prevent the solution from coming into contact with the hands.
Formaldehyde gas dissolved in water is known commercially as formalin, and contains about 40 per cent. formaldehyde gas. Information about the process of manufacture reveals that formaldehyde is made from methyl or wood alcohol and the solution usually contains some of this chemical as a stabilizer. In nearly all formalin solutions obtained on the market there is also some paraformaldehyde, a white insoluble substance derived from formaldehyde. If this substance remains in the combs they will smell of formaldehyde long after the combs have been dried. The best way to remove para formaldehyde should enough remain to be noticeable, is apparently by the use of sodium sulphite*
*A chemical used in photography costing about 25 cents a pound.
solution. Combs containing a large amount of paraformaldehyde were successfully treated at the Experiment Station by soaking after drying in a solution of this material containing 1 pound in 8 gallons of water.
The question very naturally arises whether it will pay the average small beekeeper to disinfect with alcohol-formalin solution. The minimum amount of the solution which may be used is about 10 gallons. At present prices this will cost about $15.00. It will
follow that should the value of the stock or combs infected rise greatly above this initial cost, it would be to the advantage of the person interested to make use of the solution: otherwise it would seem better economy to destroy completely the infected bees and equipment. For the larger beekeeper who is liable to encounter the disease year after year, it should be of more value. Reports from other states seem to be favorable, but the opinion of Connecticut beekeepers is not definitely formed regarding the economic value of the treatment and several years will probably elapse before we shall know whether it will receive the endorsement or condemnation of beekeepers in general.
So far our experiments have not demonstrated conclusively whether the solution will or will not control American foul brood. Work along this line is to be continued.
REFERENCES. 1. Hutzelman, J. C. Gleanings in Bee Culture, 50: 764-766: 1922. 2. Gleanings in Bee Culture, 51: 773: 1923. 3. White, G. F. American Foul Brood, U. S. Dept. Agr. Bull. 809:1920. 4. Demuth, G. S. Gleanings in Bee Culture, 51: 712-717: 1923. 5. White, G. F. Gleanings in Bee Culture, 52: 284-288: 1924. 6. Gleanings in Bee Culture, 52: 9:
1924 (editorial). 7. Root, E. R. Gleanings in Bee Culture, 52: 86-89: 1924. 8. Root, E. R. Gleanings in Bee Culture, 52: 212-214: 1924. 9. Byer, J. L. Gleanings in Bee Culture, 52: 230-231: 1924. 10. Byer, J. L. Gleanings in Bee Culture, 52: 584: 1924. 11. Gleanings in Bee Culture, 52:
43: 1924 (Gleaned by Asking). 12. Barber, 0. E. Gleanings in Bee Culture, 52: 716: 1924. 13. Gleanings in Bee Culture, 52: 138: 1924 (editorial). 14. Jones, Dan. H. Gleanings in Bee Culture, 52: 364-6: 1924.
THE EGG OF THE BLUEBERRY SPITTLE-BUG,
Clastoptera proteus Fitch.
PHILIP GARMAN. Eggs of this species were obtained in 1924 from bugs kept in, confinement on growing plants. A search during the winter brought to light many old egg punctures and some live eggs in a similar position on wild bushes. Since the eggs of the species have not been recorded it seems advisable to describe their general form and location.