APri11969
SETTEPANIET AL.: BORONCHEMOSTERILANT SA NDSCREW-WORMFLIES
383
the actual sterilizing agent when many of the effective
organoboron compounds were administered, boric
compound
Soloway, A. H.
1964.
Boron compounds in cancer
therapy, Chapter 4. In Steinberg, H., and A. L.
McCloskey [ed.] Progress in Boron Chemistry, Vol. 1.
Macmillan, New York.
acid itself would be the most convenient
for such studics.
Steinberg, D. 1964. Organoboron
Chemistry.
Vol. I.
REFERENCES CITED
John Wiley &: Sons, New York, p. 863.
Borkovec, A. B. 1966. Insect Chemosterilants.
Intersci-
1968. Insect
Steinberg, D., and R. J. Brotherton.
1966. Organoboron
cncc Publ., New York.
Chemistry, p. 26, Vol. II. John Wiley &: Sons, New
Borkovec, A. B., and J. A. Settepani.
York.
chemosterilants derived from boron. U.S. Patent Ap-
plication no. 596,727.
Zimmer, D., E. R. Andrews, and A. D. Sill. 1967. Prep-
aration, stability, and biological activity of hetero-
Lee, S., and S. Aronoff. 1967. Boron in plants: A bio-
chemical role. Science 158: 798-9.
cyclic boron compounds.
607-9.
Arzneimittel-Forsch.
17:
Responses of the Pales Weevil to Natural and Synthetic Host Attractants!
H. A. THOMASand G. D. HERTEL"
Forestry Sciences Laboratory, Southeastern Forest Experiment Station, Forest Service, USDA,
Research Triangle Park, North Carolina
ABSTRACT
llylobius pales (Herbst) responds to an attractant pres-
ent in the cut pine stem. From observation of the weevil's
behavior toward the natural attractant, a laboratory bio-
assay was developed in which paired chemicals were
placed in a choice chamber to determine their attractive-
ness to the weevils. Using extracts of stems of loblolly
pine, PintlS taeda L., we found that the principal at-
tractant occurs in the phloem and concluded that it may
be a monoterpenoid.
Bioassays of purified compounds, including some mono-
terpenoids, showed several which were attractive, particu-
larly eugenol, anethole, and d-a-pinene. The response to
the last mentioned, which makes up a large proportion
of pine oleoresin, may explain the attractiveness of the
cut pine stem to the pales weevil.
With the increased cutting and replanting
in the South, concern has developed over the accom-
panying increase in seedling losses cause by the pales
of pines
manner as thc Europeans use in trapping and killing
H. abietis. Our objective was to study the chemical
basis for pales weevil attraction as a 1st step in decid-
weevil, Hylobius pales (Herbst)
(Grady et al. 1967).
ing if it could be uscd to manipulate
the weevil.
'VEEVIL RESPONSESTO CUT PINE.-Pales
traction to cut pine is a vital process, since it is food-
seeking behavior. The basic nature of the process
was considered sufficiently important to warrant spe-
cific study. The results would be used to design
populations
of
The pales weevil problem is reduced if planting does
not follow too soon after cutting.
However,
has become un-
presently observe
after cutting (Segur
967). Undcr such a practice, the planted seedlings
for
weevil at-
economic reasons, delayed replanting
feasible, and forest managers
policy of prompt replanting
a
1
a
may suffer heavy attack from the weevil population
which develops in the roots and stumps left by cut-
laboratory bioassay which utilized normal weevil be-
havior.
ting. As the cutting and replanting
tinues, weevils may become so numerous that control
efforts with insecticides are only partially successful
sequence con-
Simulating
method of Ciesla and Franklin
that freshly cut sections of loblolly pine, Pinus taeda
L., contain an attractant (unpublished). The method
is based upon the behavior noted earlier by Pierson
(1921), whereby the weevils hide beneath the pine
natural
conditions
and
using
the
(1965), we confirmed
in preventing
seedling losses. Consequently,
alterna-
tives are necded to supplement
ling protection.
insecticides for seed-
One promising
alternative
employs either an in-
sections and can then be collected or counted by an
secticide or antifertility
agent with an attractive bait
observer.
or other attractant source (Beroza 1966). In Europe,
for example, a related weevil, Hylobius abietis L., is
caught and killed in pitfall traps before it destroys
Traveling
occurred at dusk or in the dark. By marking and
releasing weevils in plots, we could determine the
distances over which weevils responded to the attrac-
tant. When releases were made 20 ft from the plot
center, an average of 32% of the weevils was recov-
ered at the stem section in the center. A small per-
centage of weevils was recovered after release 100 ft
from the plot center.
by the weevils to the attractant
sections
the pine seedlings
tain fresh pine bark for attraction
(Novak 1965). These traps con-
and an insecticide
which kills the trapped weevils. The adult pales wee-
vil is likewise attracted by odor to cut pine for food
as well as for breeding
material.
This attraction,
observed in America at least as early as 1862 by
Harris, has been utilized to collect weevils by Pierson
This information
together with other observations
(
1921), who set out pine chips, and by Ciesla and
(1965), who used pine stem sections. The
last-mentioned cases suggest that the pales weevil
indicate that after adult weevils migrate into a fresh
cutting by flight, they remain localized, wandering
and foraging on the surface of the ground. From the
Franklin
2
can be manipulated
in the field, perhaps in the same
foregoing we concluded
that:
(1) the cut stem or
trunk of pine is attractive to the pales weevil, (2)
within 20-50 ft or more the weevils reach the attrac-
1
Accepted for publication November 13, 1968.
Entomologist and Associate Entomologist, respectively.
"
Settepani
