Historic, archived document Do not assume content reflects current scientific knowledge, policies, or practices. elle wo ee Liar ie f lease return alias: UNIT Vv, BULLETIN No. 480 Contribution from the Bureau of Entomology L. O. HOWARD, Chief Washington, D. C. A June 30, 1917 SOLID-STREAM SPRAYING AGAINST THE GIPSY MOTH AND THE BROWN-TAIL MOTH IN NEW ENGLAND. By L. H. Wortutiry, Agent in Charge of Scouting and Extermination Work, Gipsy and Brown-Tail Moth Investigations. CONTENTS. Page. Page ACT OCU HOM a= sm cere csiniesiacile an 225 235+ 268 SAE Pilea eee es MOO 2s. 2 225 240— 270 515.0 eae al ei TOO 2 See see 225 240 272 SHO) Se ees oe TS0O! 4a ee 225 240+ 275 SLOA= | poke ne ees | $A Sass ar 225 240+ 278 BOOS Tape AEA 295 245— 280 | i WG EE Ve The tables submitted are actual readings taken in the field, and the nearest to a 5-pound point was taken. Some of the variations can only be explained by the expansion of the rubber hose, which also explains the difference from the friction loss in 1-inch iron pipe. EXPERIMENT TO DETERMINE THE DISTRIBUTION OF POISON ON FOLIAGE. In order to determine how thoroughly trees were being sprayed by using the solid-stream method a number of experiments were conducted during the summer of 1916. For this purpose a series of ferrotype plates, 14 by 10 inches, were secured and treated with black coach paint so that any spray coming in contact with them could be seen. The plates were num- bered and attached to bamboo poles about 12 feet in length. This was done by splitting the small end of the pole, and after inserting the plate it was sewed in place securely with copper wire. The plates were then placed in different positions and at different heights in trees that were to be sprayed and a record secured of the effectiveness of the work. (PI. IX.) This is a methed that can be used by anyone to test the thoroughness of spraying for leaf- eating insects. One test was conducted to determine the time required properly to spray a Shade tree when the solid-stream method is used. The tree selected was 65 feet in height, and excellent results were se- cured by applying the spray for half a minute. A glance at Plates X and XI shows the thoroughness of the treatment im this test and illustrates the value of this method of spraying when properly used. 1 See Engineering Work in Towns and Small Cities, by Ernest McCullough, 1906, p. 359. Pumping Machinery, by William M. Barr, 1908, p. 108. eo he a a i ae ee SOLID-STREAM SPRAYING IN NEW ENGLAND. 11 SHADE-TREE SPRAYING. The spraying of shade trees with arsenate of lead should be ac- complished at as early a date as possible after the foliage has suf- ficiently developed. (Pl. XII.) Early spraying not only applies to the gipsy moth, but will poison many brown-tail caterpillars, as they are much earlier feeders than the gipsy moth. In the case of the elm leaf-beetle (Galerucella luteola Mill.) much is accomplished in pois- oning the adult beetles, which do a small amount of feeding after coming out of hibernation before mating and laying eggs, as they are very easily poisoned at that time. It is often argued that solid- stream spraying on street trees is too expensive and that the work can be done much cheaper with smaller apparatus. The principal reason for this is because of the low first cost of the smaller outfits. (PI. XIII.) This may be true for a single year, but for two or more years the solid-stream method is the cheaper. The total cost of the most expensive high-power apparatus on the market at the present time is approximately $1,500 for a complete equipment. It is safe to figure depreciation at the rate of 20 per cent each year, although there are machines in the field at the present time that have been used 8 years and have only required an annual overhauling and the replace- ment of small worn parts. In 20 days’ spraying one large machine should treat 10,000 shade trees. This would average only 3 cents for each tree in depreciation which is not prohibitive to any munici- pality. Taking everything into consideration, the entire cost of spraying shade trees with the solid stream does not exceed 12 cents per tree if the work is managed properly. The following figures are submitted to show how the cost per day is computed for 20 working days: LOA VOL, MOTSES) alls GIiviene tsa sass he oy a Moca $6. 00 SRIMEH So NOMS Caen Mevetaniad Moe Ven. MVE ORME Ye Fd Glide a 7.50 560 pounds of poison, at 5 cents per pound_______________ 28. 00 OSA M SO RNS AS OL CMe m ogni ae amrerenete) U8 NS Reeaen eit eae lca hone 1. 80 OT AO Ss OUR AEE SNELL SECT ER EON Ey ae ee ame 30 Depreciation per day at 20 per cent per year_____________ 15. 00 $58. 60 The average number of shade trees sprayed with each 400 gallons of poison is 35, and 14 tanks (5,600 gallons) in 8 hours is a good average, totaling 490 street trees per day, making the average cost per tree about 113 cents. In treating shade trees, where any consid- erable amount of spraying is to be done, the use of small outfits in mist spraying is much more expensive than the solid-stream method. In an experiment conducted during the summer of 1916 the cost of treatment with a small hand outfit was more than twice the amount per tree that it was when the solid stream was used. While one can 12 BULLETIN 480, U. S. DEPARTMENT OF AGRICULTURE. find considerable variation in the cost of applying the mist spray, either with gasoline or hand outfits, it is more than double the cost of solid-stream spraying, which, in the long run of the season’s work, will equal an amount that will more than two-thirds pay for a high-grade solid-stream machine and equipment. By following the mist method for two seasons a high-grade outfit has practically been thrown away and with no asset shown for money expended. WOODLAND SPRAYING. In woodland or park spraying the solid-stream method is in a class by itself, as the climbing of trees over large areas makes the mist method not only too slow but laborious and expensive. With a high- grade solid-stream machine properly equipped an average of from 12 to 15 acres can be sprayed in a day. ‘This applies to large areas where machines can be operated without the necessity of moving any great distance in the day’s work. Twenty-one acres of woodland, consisting mostly of trees 60 to 70 feet high, is the maximum treated in asingle day. (Pl. XIV.) In this instance the water supply was convenient and easily accessible. ‘The solid-stream machine for wood- land spraying should be equipped with from 1,000 to 1,500 feet of 1-inch hose; 100 feet of 24-inch suction hose, suction strainer, two noz- zles (one long and one short), and with each nozzle one of the fol- lowing tips: #5, 4, #;, 4 inch bores. The nozzles should be equipped with a brass spreader for spraying undergrowth and low foliage. (Pl. XV.) Hose should be provided with couplings that will not blow out—if expensive delays are to be avoided. Spraying in wood- land should be arranged so that whenever possible the location of the hose may be changed while the sprayer is being filled. Much time will be lost if this is not done, and 10 men are usually necessary where long lines of hose are being used, Men should be so located on hose lines that the nozzlemen will not be hindered by the weight of hose. The number of men needed in woodland spraying is determined entirely by the lengths of hose used. One hundred feet of 1-inch 8-ply cotton-covered hose weighs 84 pounds, and carries 4.8 gallons of water weighing 32.64 pounds, making the total weight when spraying 116.64 pounds. This makes it necessary to assign a man to every 100 feet, besides the nozzleman. The cost of woodland spraying where large areas are involved aver- ages about $5.50 per acre. Where only small areas are sprayed the cost is much greater. Six hundred gallons of solution, when prop- erly applied, will usually spray an acre and no climbing should be necessary. In experiments recently conducted, a pine tree 994 feet high was successfully sprayed from the ground. Good results can usually be obtained in woodland spraying by directing the stream through the open places in the foliage in order to minimize damage Bul. 480, U. S. Dept. of Agriculture. PLATE IX. eh WS at BAe TESTING THE DISTRIBUTION OF POISON SPRAY. Spraying elm tree 65 feet high with solid stream. Note the plates at top of tree which were used to secure a record of the distribution of the poison. (Original.) ) PLATE X. al in xX, (Orig Plate I hown in siss ate e pl a f the 10no RESULTS OF TESTS FOR DISTRIBUTION OF POISON SPRAY. tribution of poison. Locati S S Di Bul. 480, U. S. Dept. of Agriculture. PLATE Xl. al.) In - (Origi x in Plate I hown Is $ ates ion of these pl Locat 1son f po > < a a ip) z je) 2 Oo ou LL ie) z ie) FE 2 a a = 2 QO og O LL op) E (op) uu - LL ie) 7p) FE = 2 (72) ul oc Distribution o Bul. 480, U. S. Dept. of Agriculture. Bul. 480, U. S. Dept. of Agriculture. PLATE XII. THE SOLID-STREAM SPRAYER IN OPERATION. Spraying shade trees along the streets with solid stream. (Original.) Bul. 480, U. S. Dept. of Agriculture. PLATE XIII. THE UNSATISFACTORY, OLD-TIME SPRAYING OPERATION WITH A HAND OUTFIT. Spraying shade trees with hand outfit. Those eee to be climbed in order to treat the tops. (Original. Bul. 480, U. S. Dept. of Agriculture. PLATE XIV TESTS FOR DISTRIBUTION OF POISONED SPRAY AT EXTREME HEIGHTS. Spraying oak 85 feet high in woodland. Note the distribution of the poison spray on the plate located at top of tree. (Original.) Bul. 480, U.S. Dept. of Agriculture. PLATE XV. ADAPTATION OF THE SPREADER IN SPRAYING OPERATIONS. Spraying low growth, using spreader. (Original.) PLATE XVI. Bul. 480, U. S. Dept. of Agriculture. (‘{eUuIsIIQ) ‘1epeolds ZuIsn ‘uIveI}S pIfOs TIA preyolo Surkeidg SNOILVYAdO DNIAVYdS -GYVHOYO OL YS0VEYdS JO NOILVidvay SOLID-STREAM SPRAYING IN NEW ENGLAND. 13. to the leaves, and at the same time thoroughly treat the surrounding foliage. By using a spreader on the nozzles the lower foliage and undergrowth can be properly sprayed with much less damage or loss of solution than if the solid stream is applied. The essential thing in woodland spraying is to keep the nozzleman moving. Poison is sure to be wasted when stops are made for any length of time. Care- ful arrangements for water supply should- be made in advance. Damming of brooks or digging holes in low ground to provide an accumulation of water will reduce the cost of spraying to a great extent. It sometimes becomes advisable in the spraying of large wooded areas to build temporary roads. This is often necessary from an economic standpoint, as the average wood road suitable for spraying machines can be built for 5 cents per square yard, and re- sults in a great saving in the aggregate spraying cost. Especial care should be taken in the spraying of conifers, as the leaf area is very small and the stream must be broken into a fine mist in order to have the solution adhere. WINTER CARE OF SPRAYING MACHINES AND EQUIPMENT. Failure to take proper care of a spraying outfit is responsible for most of the difficulties and delays that result during the spraying season. This is particularly true in regard to the precautions that should be taken when the spraying season is over and the machine is jaid up for the winter. If careful attention is not given to the appa- ratus at this time, many difficulties and delays are likely to result during the following season. Each machine should be taken to a convenient water supply and clear water forced through the pump and hose until both are per- fectly clean. The running gear should be thoroughly washed. After this has been done the hose should be laid away for the winter. Stor- ing hose in coils should be avoided. The machine should be properly drained of water and all metal parts coated with heavy grease. Care should be taken that all valves and petcocks are open, and the plugs and packing in the pump should be removed for the winter to allow the latter to drain. After the water has been properly drained from the engine and the circulating pipes have been disconnected the engine should be started and run for a few minutes so as to force the water out of the pump and check valves into the water jacket of the engine, where the heat will cause it to evaporate. Care should be taken not to allow the engine to become overheated while being run under the above conditions. After this has been done the spark plugs should be removed and wrapped in oiled cloth to prevent rusting. After the spark plugs have been removed, pour a cupful of cylinder oil into each cylinder and turn the engine over a few times, so that the oil may be worked in around the piston rings. Cork stoppers should be placed 14 BULLETIN 480, U. S. DEPARTMENT OF AGRICULTURE. in the spark-plug holes to prevent moisture from entering the cylin- ders. The panels should be taken from both sides of the engine and all oil removed from crank case, after which the crank shaft and connecting rods should be coated with heavy grease. A few drops ef hght oil should be worked into all metal parts of the magneto bearing to prevent rusting. SUMMARY. The subject of spraying, either solid-stream or mist spray, should be given very careful consideration, as the importance of securing good results is imperative. If they are accomplished, much more interest and cooperation may be expected in the problem of con- trolling leaf-eating insects. It often happens that those responsible for the results do not give sufficient attention to important details until it is too late in the season to secure the best results. One should familiarize himself with every phase of spraying, so that he may be able to cope with all conditions. While there are still those at the present time who do not feel that solid-stream spraying with arsenate of lead can be as effective as that done with smaller machines and mist nozzles, all will concede that much good work has been accomplished in the gipsy-moth area in New England with solid-stream spraying. While the solid-stream method is confined almost entirely to shade- tree and forest spraying it has been used successfully in orchards (Pl. XVI). Solid-stream work is not necessarily confined to the highest-power machines, as good results may be obtained on a small scale with medium-power machines capable of delivering a solid stream of smaller size, and which at the same time may be easily converted to mist-spray work. This also applies to the larger machines. The problem of fighting the gipsy moth and the brown-tail moth 1s of such magnitude and general economic importance that it would be impossible to do the necessary spraying in the infested area with mist spray and small machines. During part of many seasons the weather is not suitable for spraying, and when conditions are right a large amount of spraying must be accomplished in a short time. The work of several boring insects which have riddled our shade trees in the past few years has also made chmbing of them much more hazardous, but this must be done if the mist spray is used. If climbing is resorted to, the expense is prohibitive, especially in wooded areas. Many times the question is asked, “ Why pursue other methods of fighting the gipsy moth and the brown-tail moth; why not confine it entirely to spraying?” There are several reasons; the nature and severity of the infestation must be taken into consideration, — and the proximity and danger of spread to noninfested regions. If extermination is to be expected it would not be wise to confine all SOLID-STREAM SPRAYING IN NEW ENGLAND. 15 efforts to spraying. If the infestation is severe and egg clusters are very numerous they should be treated with creosote prior to spraying. What is termed “rough creosoting” consists of treating the egg clusters, which can be easily reached in areas to be sprayed. In rare cases infested shade trees are located near buildings where it is impossible to spray without defacing the buildings to some extent. This can be avoided, however, if buildings are first wet with clear water. If the infestations are located in pasture lands, prope precaution should be exercised so that live stock will not be poisoned. Poison notices should be placed in conspicuous places in all locations where spraying is done. From 800 to 1,000 tons of arsenate of lead and about 500 high- power solid-stream machines are being used each year in the New England States in fighting the gipsy moth. Thousands of acres of park and orchard trees and woodland in addition to approxi- mately 20,000 miles of street trees are being sprayed. When spray- ing 1s properly done to control the gipsy moth, very little trouble is experienced with other leaf-eating insects. PUBLICATIONS OF THE U. S. DEPARTMENT OF AGRICULTURE RELATING TO THE GIPSY MOTH AND THE BROWN-TAIL MOTH. AVAILABLE FOR FREE DISTRIBUTION. The Gipsy Moth and the Brown-tail Moth, with Suggestions for their Control. (Farmers’ Bulletin 564.) Report on the Gipsy Moth Work in New England. (Department Bulletin 204.) Control of the Gipsy Moth by Forest Management. (Department Bulletin 484.) FOR SALE BY THE SUPERINTENDENT OF DOCUMENTS, GOVERNMENT PRINTING OFFICE, WASHINGTON, D. C. Danger of General Spread of the Gipsy pad Brown-tail Moths through Im- ported Nursery Stock. (Farmers’ Bulletin 453.) Price, 5 cents. Food Plants of the Gipsy Moth in America. (Department Bulletin 250.) Price, 10 cents. Z The Calosoma Beetle in New England. (Department Bulletin 251.) Price, 15 cents. Dispersion of Gipsy Moth Larvze by the Wind. (Department Bulletin 273.) Price, 15 cents The Gipsy Moth as a Forest Insect. (Entomology Circular 164.) Price, 5 cents. : The Gipsy Moth in America: An Account of the Introduction and Spread of Porthetria Dispar in Massachusetts and of Efforts made by the State to Repress and Exterminate It. (Entomology Bulletin li, n. s.). Price, 5 cents. Report on Field Work Against the Gipsy Moth and the Brown-tail Moth. (Entomology Bulletin 87.) Price, 35 cents. Importation Into the United States of Parasites of the Gipsy Moth and the Brown-tail Moth: A Report of Progress, with Some Considerations of Pre- vious and Concurrent Efforts of this Kind. (Entomology Bulletin 91.) Price, 65 cents. Calosoma Sycophanta, Its Life History, Behavior, and Successful Colonization in New Engiand. (Entomoiogy Bulletin 101. Price, 25 cents. The Dispersion of the Gipsy Moth. (Entomology Bulletin 119.) Price, 20 cenis. 16 ADDITIONAL COPIES OF THIS PUBLICATION MAY BE PROCURED FROM THE SUPERINTENDENT OF DOCUMENTS GOVERNMENT PRINTING OFFICE WASHINGTON, D. C. AT 15 CENTS PER COPY V WASHINGTON : GOVERNMENT PRINTING OFFICE : 1917 ——_— a a ee