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A large seod establishment at Bristol, Pa«, announced a new and 
natural control for the Japanese beetle. T/fhen castor-beans were plant- 
ed a short distance from the flowers, the beetles left the flowers and 
swarraed over to the castor-beans, eating the large leaves. These 
plants caused slow but sure death, and great piles of beetles were 
swept up from under them each morning. Ten cents worth of castor- 
bean seed planted a short distance from a gsurden was considered to 
help solve the Japanese beetle problem.—Landreth (31, 32) • 
Owing to the publicity given to this discovery, a series of 
tests was conducted by the Bureau of Entomology and Plant Quarantine 
at its Japanese beetle laboratoxy in 1932 to determine the attrao*!- 
tiveness and toxicity of the castor-bean plant to the Japanese beetle. 
Tests were made on 6 varieties of this plant— 'cambodgensis , panor - 
mitanus , gibsoni . Red Spire, sanguineus, and zanzibarens is— grown at 
lioorestoTin, N« J. The beetles fed on the foliage of sanguineus and 
Zanzibar ensis, but the other varieties were practically immune. 
Large numbers of dead beetles were foxind under these plants, but they 
could also be found under other plcmts heavily infested by this in- 
sect. Under certain field conditions, however, castor-bean foliage 
appeared to be toxic to the beetles. In cage tests they fed on the 
foliage to a limited extent. However, no tested variety of castor- 
bean ¥ras sufficiently attractive to indue© the beetles to leave fa- 
vorite food plants nearby. It was concluded that the castor-bean 
plant was of little or no value as a trap plsmt for the beetles 
under usual field conditions.— Metzger (34) » 
Japanese beetles do not feed on all varieties of castor-beans, 
and the toxic property of varieties fed on it not at all uniform. 
Certain varieties do have some killing power, but it is not nearly 
so great as has been alleged by those advocating the use of this 
plant to destroy the insect.— Hawley and Metzger (27). 
An extension horticulturist received a letter from a gardener 
in northern New Jersey requesting an immediate visit to see what 
he had discovered concerning beetles on his lima beans. About 100 
feet from the beans the gardener had planted a row of castor-beans j 
on inspection, he found the ground beneath the castor-beans covered 
with hundreds of dead beetles, probably Asiatic garden beetles ( Auto - 
8 erica cast an ea (Arrow)). The leaves showed evidence of feeding by 
the beetles. — Nissley (37) . 
In some parts of Manchuria the castor-bean plant was cultivated 
with other plants to prevent in.iury to the latter by insects. Adult 
beetles ( Autoserica orientalis (Motsoh.)') that had fed on these 
leaves for 24 minutes in the lail)oratory became p€a*alyzed in 56 minutes 
and died after 157 hours; outdoors, 94 percent died in 4 days. 
Recovery from the paralysis was 6 percent outdoors and 35 percent in 
the laboratory. — Tsuchiyaroa (48) . 
