thras hers. Thes e and many other bi rds were s harply reduce d els ewhere. Pheas ant hunte rs felt
the effects of the beetle campaign s harply. The numbe r of broods produced on treate d lands
fell off by s ome 50 per cent, and the numbe r of young in a brood declined. Pheas ant hunting,
which had been good in thes e areas in former years , was virtually abandoned as unrewarding.
In s pite of the enormous havoc that had bee n wrought in the name of eradicating the Japanes e
beetle, the treatme nt of more than 100,000 acres in Iroquois County ove r an eight-year period
s eems to have res ulted in only te mporary s uppres s ion of the ins ect, which conti nues its
wes tward move me nt. The full extent of the toll that has been taken by this largely ineffective
prog ram may neve r be kn own, for the results measured by the Illinois biologists are a minimum
figure. If the res earch progra m had bee n adequately financed to permit full coverage, the
des truction revealed would have been even more appalling. But in the eight years of the
prog ram, only about $6000 was provided for biological field studies. Meanwhile the federal
government had s pent about $375,00 0 for c ontrol work and additional thous ands had been
provided by the s tate. The amount s pent for res earch was therefore a s mall fraction of 1 pe r
cent of the outlay for the chemical program.
Thes e midwes tern programs have bee n conducte d in a s pirit of cris is , as though the advance of
the beetle presented an extreme peril justifying any means to combat it. This of course is a
dis tortion of the facts , and if the communities that have endured thes e chemical drenchings
had been familiar with the earlier history of the Japanese beetle in the United States they
would s urely have been les s acquiescent. The eas tern s tates , which had the good fortune to
s us tain their beetle invas ion in the days before the s ynthetic ins ecticides had been invented,
have not only s urvived the invas ion but have brought the ins ect unde r control by means that
represented no threat whatever to other forms of life. There has been nothing comparable to
the Detroit or Sheldon s prayings in the Eas t. The effective methods there involved the bringing
into play of natural forces of control which have the multiple advantages of permanence and
environmental safety. During the firs t dozen years after its entry into the United States , the
beetle increased rapidly, free of the restraints that in its native land hold it in check. But by
1945 it had become a pes t of only mi nor importa nce throughout much of the te rrit ory over
which it had s pread. Its decline was largely a consequence of the importation of parasitic
ins ects from the Far East and of the establishment of disease organisms fatal to it.
Between 1920 and 1933, as a res ult of diligent s earching throughout the native range of the
beetle, some 34 species of predatory or paras itic ins ects had been imported from the Orient in
an effort to establish natural control. Of these, five became well established in the eastern
United States. The most effective and widely distributed is a parasitic was p from Korea and
China, Tiphia vernalis. The female Tiphia, finding a beetle grub in the soil, injects a paralyzing
fluid and attaches a s ingle egg to the unders urface of the grub. The young was p, hatching as a
larva, feeds on the paralyzed grub and destroys it. In s ome 25 years , colonies of Tiphia were
introduced into 14 eastern states in a cooperative prog ram of state and federal agencies. The
wasp became widely established in this area and is generally credited by entomologists with an
important role in bringing the beetle unde r control. An eve n more important role has been
played by a bacterial disease that affects beetles of the family to which the Japanese beetle
belongs—the scarabaeids. It is a highly specific organism, attacking no other type of insects,
harmless to earth wo rms , warm- blooded animals , and plants. The s pores of the dis eas e occur in
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