History of Rutgers' Department of Entomology - part 25.
The Japanese beetle was first discovered in this country by Harry B. Weiss and Edgar L. Dickerson about the middle of August, 1916, while they were inspecting the nursery of Henry A. Dreer, Inc., about two and one-half miles east of Riverton, New Jersey. A dozen or so specimens were collected because it was recognized as new to New Jersey. No further attention was paid to the specimens until the spring of 1917, when attempts to identify the species as American failed. Specimens were then sent to the United States National Museum and identified as Popillia japonica, by H. S. Barber. As soon as it was recognized as a Japanese species, Weiss looked up the Japanese literature for additional information and concluded that the species was a serious threat to agriculture. On August 8, 1917, the nursery was visited again and the insects were found to be abundant in a rather small area, especially on smart-weed. It was probably imported in the grub stage in iris roots which the nursery had imported from Japan five or six years before. The Federal Bureau of Entomology became interested and A. L. Quaintance sent W. 0. Ellis to Riverton to study its life history. Because it appeared to be a potential pest, David F. Houston, then Secretary of the United States Department of Agriculture, was induced to make $5,000 available during the period ending June 30, 1918, for further study. The State Legislature also made $5,000 available beginning July 1, 1918. From then on increasing attention was given to the insect. W. 11. Goodwin, from the Federal Bureau of Entomology, was sent to Riverton in May, 1918, and after two months of investigation a plan was developed which, it was hoped, would prevent the beetle from spreading.
This plan proposed to limit the spread of the beetle by spraying, with arsenate of lead, a half mile-wide band of non-economic foliage around the heavily infested area, leaving patches of unsprayed grassland for egg deposition. These grassland areas were to be saturated with sodium cyanide in water to kill the immature stages. Twelve light trap stations each of 400 candlepower were to be used to attract beetles to pans of kerosene. All food plants of the beetle were to be dusted with powdered arsenate of lead in a suitable carrier. The beetles were also to be hand-picked and killed. Clean cultivation of farm lands was advocated and infested sod land was to be treated with carbon bisulphide. All green sweet corn in the area was to be removed under quarantine regulations.
An attempt was made to put all these plans into effect from 1918 to 1921. However, adequate funds were lacking, labor was scarce, and it was impossible to keep the protective band of vegetation continuously coated with arsenate of lead. The first applications were washed off by rains before the remainder of the band could be covered. Moreover, the beetles paid no attention to the sprayed foliage and, being strong fliers, they readily found unsprayed foliage upon which, to feed. Goodwin resigned and was succeeded on May 1, 1919, by J. J. Davis. A laboratory and office were established at Riverton and an advisory committee was set up consisting of Headlee and A. L. Quaintance. C. H. Hadley represented the Federal Horticultural Board in the matter of the inspection and certification of green sweet corn and problems of spread.
By 1920 eradication of the beetle was given up and from then on retardation was the aim. This was to be attained by a general quarantine and by suppression of the beetle within the infested area. Scouting was done each year to determine the limits of infestation. Badly infested areas were heavily cyanided and also sprayed with commercial lime-sulphur plus hydrated lime. Seven power sprayers and seven dusting machines operated. Clean-up work was done on headlands, roadsides, etc. Boys and girls were paid for each quart of dead beetles that they had hand-picked and killed. In general these efforts did not make a visible dent in the beetle population, and by 1919-1920 the beetle occupied fifty square miles in New Jersey and had invaded Pennsylvania between Holmesburg and Torresdale.
While these retardation efforts were going on, the laboratory was making life history studies searching for insecticides for use against adults and grubs as well as a method of treating balled earth infested by grubs.
Both Federal and State quarantines were made effective during 1920-1921, and the enforcement of the State regulations was delegated to the joint agent-in-charge under the supervision of C. W. Stockwell. Inspection and certification were required on all farm, nursery, and greenhouse products. At that time the quarantine work required thirty-seven men, two Ford trucks and a number of bicycles. In the spring of 1920 C. P. Clausen went to Japan for parasites and was followed later by J. L. King. During 19201921 the State spent $15,000 and the Federal Government $100,000 on the project. A part of the state appropriation was allotted to the Federal laboratory because the Department was anxious to further any work leading to the discovery of better control methods for the beetle that could be used by New Jersey producers. John J. Davis resigned in 1920, and was succeeded by Charles H. Hadley, who directed the project as a joint agent. After Hadley resigned in October, 1923, he was succeeded by Loren B. Smith, who had been connected with the laboratory since 1921. Smith remained until 1928, at which time Hadley returned and continued until 1952 when he was succeeded by Walter E. Fleming who is now in charge of the Japanese and Asiatic beetle investigations for the Federal Government.
By 1921 approximately 213 square miles of territory were infested in New Jersey, in comparison with one-half square mile in 1916. Studies of the beetle had developed the fact that it had more than 200 food plants, including practically all the economic crops grown in the state. In addition to the foliage that was destroyed by the adults, the grubs were a serious pest in lawns, golf courses, and pastures. Some pastures had as many as 700 to a square yard.
Scouting was continued each year in connection with the quarantine regulations and also to determine the general spread of the beetle. Each year the quarantined area increased and each year it was necessary to scout the sand, moss, peat, salt hay, marl, and nursery and greenhouse surroundings in connection with the enforcement of the quarantine. In 1921-1922 tachinid parasites were received from Japan, also a predaceous beetle which did not survive in New Jersey. Good results were reported at this time from the use of arsenate of lead with flour as a sticker and spreader. This gave protection to the foliage but the kill of beetles was not so good.
Research and quarantine work were carried on intensively in succeeding years and every angle that promised improved methods of beetle control was investigated. In 1923-1924, the refrigeration of soil-balls for killing grubs on the roots of evergreens was tried. Carbon bisulphide emulsion was found effective in killing grubs in lawns and in the soil around the roots of rhododendrons, azaleas, blueberries, etc. Seven thousand adults of the parasite Centeter cinera were released between Riverton and Moorestown. Studies of the fungus and bacterial diseases of the beetle were carried on and chemotropic studies were made on the adult beetles. Various attractants were studied and geraniol was found to be distinctly attractive. A process of coating arsenate of lead with an insoluble soap such as lead oleate was devised. This gave more protection to the foliage and killed more beetles. A pyrethrum soap was also developed.
By 1924-1925 the Federal Government was spending $241,000 on the beetle, and New Jersey $45,000, and the heavily infested area in the state had increased to 500 square miles. Nine hundred thousand packages of farm products were being certified for shipment to points outside the quarantine area and over 11,000 trucks of produce were being stopped at the boundaries of the regulated area to determine if the contents had been properly certified. Seventeen thousand carloads and 400 boatloads of sand were certified and, in many cases, treated before certification,
The next year, the commercial use of geraniol was developed and traps were built and baited that were capable of capturing from three to four quarts of beetles daily. A hot water treatment for nursery stock was devised. Improvements were later made in the beetle traps and a mixture of geraniol, eugenol, bran, molasses, and glycerin was used as bait. The liberation of parasites continued. The Japanese beetle laboratory was moved to Moorestown in 1926.
By 1929 the laboratory was making ecological studies of the beetle and testing the effect of a high frequency electrostatic field on insects and plants. Various fumigants were looked into and ethylene oxide gave promise. Carbon bisulphide vapor was used in treating baskets of fresh fruit to kill beetles.
During the latter part of 1927, the quarantine headquarters were moved to White Horse, New Jersey. After the beetle had spread naturally over the entire state, scouting to determine spread was discontinued, but it was still necessary for many years to scout the premises and surroundings of nurseries and greenhouses in order to determine their status with respect to infestation and compliance with quarantine regulations.
By 1932, Japanese beetle traps were supplanting manual scouting in the northwestern part of the State, but after 1934 such trapping activities were discontinued. Paradichlorobenzene, carbon bisulphide, arsenate of lead, and steam were in use as soil treatments at this time. Farmland scouting as a basis for granting certification was also discontinued around 1935. Fumigation of refrigerator cars was started in 1936 with liquid cyanide, but the following year, because of damage from the use of cyanide, close inspections were substituted and shippers were allowed to use prefumigated empty cars after the potatoes had been run over a mechanical grader in a warehouse. In 1938 methyl bromide began to be used as a fumigant, and by 1942 the use of methyl bromide had replaced the manual inspection of white potatoes, peppers, blueberries, and apples. At that time balled nursery stock was being treated with an ethylene dichloride emulsion and the areas in the nurseries treated with arsenicals began to decrease. Beginning with 1943-1944, truckloads of farm products were fumigated with methyl bromide.
After the entire state became infested, the state quarantine was repealed. Over the years the Federal quarantine has been modified to permit the use of new insecticides and changed to conform with changes in infestations. As the infested territory in the United States increased in size, many shippers who did not consign theirproducts to points outside of the quarantine area experienced relief from compliance with regulations and treatments. In 1947-1948 DDT treatments were approved for the certification of white potatoes shipped in refrigerator cars and closed trucks. Two dosages are required, one before and one after loading. In many other instances DDT has replaced methyl bromide as a fumigant and ethylene dichloride-dibromide has replaced carbon bisulphide as a surface treatment for small areas.
From 1921 to the present, the Federal Japanese beetle quarantine, designed to retard the artificial spread of the insect, has involved the inspection, treatment and certification of millions of items including farm, nursery, and greenhouse products, soil, sand, moss, etc. Although the regulations have been the subject of much criticism and although shippers have experienced additional expense and inconvenience in varying degrees, the fact remains that New Jersey's markets have been and are being kept open as a result. From 1921 to 1923, when the infested area was small, barely a half million packages of farm products were certified each year. As the area increased in size, so did the number of certified articles. From 1924 to 1930, inclusive, well over a million packages of farm produce were certified yearly for shipment to points outside the infested area. In addition, the yearly number of nursery plants certified varied from thirteen to twenty-eight million. Certified bales of hay, straw, and moss varied from eighteen to eighty thousand annually, and boxes of cut flowers from one to seven thousand. From six to twelve thousand carloads of sand, soil, and peat were certified yearly during that period.
Since 1931 there has been a gradual decline from the high figures of previous years, but from 700,000 to a million packages of farm products are being certified each year, along with from four to six million nursery and greenhouse plants. Hay, straw, and moss have not needed certification since 1935. Boxes of cut flowers now range from 200 to 400, and practically no sand or large soil shipments are certified at present. However, the recent sales of small packages of soil to city dwellers for house plants has made it necessary to certify about a thousand packages annually. In addition to the inspection and certification, various soil treatments are supervised.
At present, nursery stock may be certified in various ways, such as by freeing the roots from soil, growing the plants in certified areas which have been chemically treated, fumigation with gaseous insecticides, treatment with liquid insecticides, and using an insecticide with potting soil. Cyanide, methyl bromide, ethylene dibromide, ethylene dichloride, carbon disulphide, chloropicrin, arsenate of lead, and DDT are used in the certification work. Farm products are given certification after approved methods of grading and packing have been met, after fumigation or after manual examination, depending upon beetle conditions.
Immediate supervision of the quarantine work in the state has usually been by a joint agent of both state and Federal governments. George K. Handle was this agent from 1927, until his resignation in 1934. John H. Harman succeeded Mr. Handle in 1934, and remained until transferred to Ohio in 1949. Since then Leon D. Gray has been in immediate charge. In 1943, Edgar G. Rex was given charge of the grounds, buildings and, automotive equipment at White Horse, and since 1947, Frank A. Soraci has looked after the department's interests in quarantine matters. J. Gilbert Sholin had charge of the Japanese beetle office from 1928 to 1941, after which he was succeeded by Charles B. Robinson.