Off Limits for Beetles

Wi1liam Middleton, Timothy C. Cronin.

Three years after the Japanese beetle was discovered in New Jersey, the Department of Agriculture of that State instituted a quarantine to try to prevent the spread of the beetle. The effort was not successful. By 1919 the beetle had begun its relentless march. In its new home it found many plants it could feed on, extensive turfed areas to breed in, and none of the natural enemies that held it in check in its native Japan.

So the United States Department of Agriculture invoked a Federal quarantine.

The action was taken under the Plant Quarantine Act of 1912, which authorizes the Secretary of Agriculture to quarantine any State, territory, or district when he determines that a quarantine is necessary to prevent the spread of a dangerous insect or plant disease and to cooperate with any State, territory, or district in connection with any quarantine they enact.

Federal quarantines apply only to interstate movement of regulated articles, and hence entire States are quarantined. If it is necessary to prevent or retard the spread of a pest into an uninfested part of a State under Federal quarantine, authority to control movement within the State must be used the Secretary designates the regulated area within the State and a State official issues a quarantine paralleling the Federal instrument as to area, articles, and conditions.

The Secretary's original quarantine order against the Japanese beetle became effective June 1, 1919. It was under the direction of the Federal Horticultural Board, with the Federal Bureau of Entomology and the State of New Jersey as cooperators. The quarantine prohibited the movement of ears of green corn, unless inspected and certified as beetle-free, from three townships in Burlington County, N. J., where the beetle was first found in this country.

As the beetle continued to spread naturally and more was learned about it, changes were made in the areas regulated and additional materials were restricted. In 1920 the area regulated by Federal quarantine was extended to include a small part of adjacent Pennsylvania, and the movement of general farm products, nursery and greenhouse stock, and soil was restricted. In 1924 Delaware was placed under quarantine. In 1926 the quarantine was extended to New York and Connecticut. Meanwhile further changes were made in the regulations pertaining to the movement of materials and in quarantine procedures; under some conditions the shipping of some articles were prohibited entirely. By 1937 the Federal quarantine had been extended to include all the States under regulation by June 30, 1951.

On March 30, 1951, a public hearing was held in Washington, D. C., to determine whether the quarantine should be revoked or continued and extended to other States. The hearing was attended by many State officials and spokesmen of industry. Opinion was unanimous against revocation of the quarantine. The Federal quarantine therefore was extended to include North Carolina, as of August 14, 1951.

The District of Columbia and 15 States were under Federal quarantine in 1952. Entirely under regulation were Connecticut, Delaware, Maryland, Massachusetts, New Jersey, Rhode Island, and the District of Columbia. Maine, New Hampshire, New York, Ohio, Pennsylvania, Vermont, Virginia, West Virginia, and North Carolina were partly regulated. The area under Federal quarantine regulation totaled about 172,000 square miles, about one-twentieth of the total area of the United States. Some localities were under State regulation in Ohio, North Carolina, Virginia, West Virginia, and Missouri.

The regulations of the quarantine in 1952 prohibited shipping live beetles to nonregulated destinations, and regulated the shipments of commodities and materials that might harbor the insects soil, peat, compost and manure, nursery and greenhouse stock, and fresh fruits and vegetables. There also were provisions for cleaning and treating vehicles and aircraft to kill or remove the beetles before the conveyances reached nonregulated areas. There were various exemptions, conditions that determine the applicability of the quarantine restrictions, and methods of compliance.

THE PROBLEM of preventing spread of the beetle and at the same time permitting movement of regulated articles is complex. Because in the beginning little was known about the insect or its control, the first quarantine measures contained few practical methods of permitting movement of regulated materials. Such an embargo type of quarantine produced complaints and demands by shippers of plants and farm products for every possible easement, including extension of regulated areas to which unrestricted shipments could be made. The needs of shippers were viewed sympathetically even at that time, but there was some resistance to rapid expansion of regulated areas, because of a desire to avoid quarantine and a hope for retardation of spread.

The conflicting interests had to be considered in the development of a sound policy. The immediate policy was to extend the regulated areas and to find out more about the beetle itself. Large areas in quarantined States were placed under regulation because relatively small numbers of beetles were found in scattered localities. A force of Federal and State entomologists and other workers cooperated with quarantine officials and industry in the research; the nature and the amount of the information required made extensive study necessary. Desired changes in the quarantine procedures and methods of compliance consequently were delayed. The basic needs were to determine the hazards of artificial spread, the methods of determining the presence and distribution of the insect, and safe, effective, and cheap methods of control and certification.

Early in the development of the quarantine the regulations divided certification activities into two parts. One phase dealt with grubs, eggs, and pupae, which were found about plant roots and in soil. That was a year-round problem. The other involved only the adult beetle, which might be transported with farm products and flowers a problem only when adults were present. That division of activities persisted, but the part dealing with the adult beetle was divided later to include a study of dissemination by vehicles, including aircraft.

The affected producers and shippers of plants and farm products were handicapped by quarantines, but most seriously affected were the nursery and greenhouse establishments. They were under regulation throughout the year and in the entire regulated area. Among them were large commercial organizations, which produce many varieties of plants under different conditions, as well as small specialists. They had shipped their products throughout the country. Certification of plants at first was almost entirely on a free-from-soil basis, but that was not always practical. Hence alternative methods under the varying conditions were needed.

A practical certification treatment requires a minimum of chemical, time, equipment, and labor, and reasonable temperature limitations. The procedures also have to be adaptable to the routine work in the industry. In the early period, the development of treatments was limited by the quarantine requirement that complete insect mortality occur before certification, a requirement that narrowed the margin of safety between insect mortality and plant injury. Few effective insecticides were available.

During the next years, treatments with carbon disulfide, lead arsenate, heat, paradichlorobenzene, and naphthalene were approved. Many plant producers used the treatments, but the regulated establishments were still under a handicap in competing with unregulated establishments.

Beginning in the late 1930's, the development of insecticides having residual action made it possible to authorize more practical treatments as a basis for certification. The development had an important effect on the quarantine program. It made available to large and small plant producers and shippers alternative methods of treating their products. While there is no cure-all treatment, they now have a choice of 16 low-cost and effective treatments, which may be applied safely to most regulated articles. Treatment may be done before or at shipping time. Methyl bromide, ethylene dichloride, ethylene dibromide, DDT, and chlordane are some of the chemicals used. All treatments for certification must be applied under the observation of a quarantine inspector. The establishment provides all material and labor and assumes all risk of injury. Before subjecting large numbers of plants to treatment, a plant owner is urged to treat sample quantities to ascertain plant tolerance.

An accompanying table shows the quantities of plants, potting soil, and plant-growing areas treated for quarantine certification from 1924 through 1950. It illustrates the volume of materials certified after treatment with the newer chemicals since the late 1930's. In 1950 more than 400 commercial plant growers in 15 States and the District of Columbia used one or more of the treatments to make plants eligible for shipment under quarantine certification. Although the treatments were used for the purpose of certifying material under the quarantine, growers who found it necessary to use them had important side benefits including control of injury by the Japanese beetle and of many other insects, weeds, and fungi. For example, chlordane soil treatment is reported to control the Taxus weevil; DDT and methyl bromide, many other soil-inhabiting insects; chloropicrin, fungi; and carbon disulfide, weeds.

SPECIAL QUARANTINE regulations are required for farm products. They apply only during the summer in areas where the abundance and activity of the adult beetles present a hazard of spread through movement of those commodities. In general, only commercial shipments are involved. Coincidental with the development of treatments for plants and soil, practical methods of treating the commodities for shipment under certification were developed. Methyl bromide fumigation was the treatment most generally used in 1951.

Before these later, more efficient, treatments became available, certification methods required the services of many inspectors for volume plant inspection on a piece-by-piece basis or treatment and for other certification activities. Because of the progress in methods, materials, and equipment, industry generally has found the quarantine regulations less burdensome, and fewer men are needed for inspection services.

So today, despite a larger regulated area, more establishments, a larger volume of certification, and higher costs, reasonable protection is being given to uninfested parts of the United States. Present operations permit the decentralization of the inspection force, which is distributed at convenient locations on a work-load basis.