DISCUSSION
 Chemical pest control does not always offer the small farmer
engaged in traditional subsistence farming a sufficient increase in
productivity to compensate for the costs of applying insecticides
over a whole field (Brader, 1982). Pesticide usage has primarily
benefited larger farmers with substantial cash crops. Although
subsistence farming is uncommon in the U.S. Virgin Islands,
there are small home gardens and some small cash crop farms.
The CVIAES and Cooperative Extension Service have encouraged
these endeavors and are continuing to apply simplified integrated
pest management principles where possible.
 Melonworm control on cantaloupe by the ichneumon A. carib-
baeum may be feasible and its future use will depend on ex-
perimental field releases currently planned. Satisfactory aphid
control on cantaloupe from predators and parasites did not occur
and insecticides were needed when the plants were young or leaf-
curling and death would soon follow on these relatively sensitive
plants. Ant control measures such as bait applications or soil
drench treatment of nests may help to delay aphid population
buildup. This would provide more lead time for natural control
agents to establish high populations.
 In contrast to cantaloupe, moderate to good aphid control on
asparagus beans by natural enemies did occur, although there
may be a high degree of risk unless predator populations are
monitored. Asparagus bean seedlings with high initial aphid
populations (50- aphids per entire plant) grew poorly and
mature plants with high populations had inferior quality pods
and aphid masses on the basal portions of the pods. The use of
insecticides for aphid control is warranted in these cases. Plants
with moderate to high aphid populations (6-20 per plant sample)
four to seven weeks after emergence developed severe infestations
as harvest approached but most of the aphids were killed by


predators and parasites over a one- to two-week period. Syrphid
larvae initiated aphid predation followed shortly by lacewing lar-
vae and lady beetle adults. One week before the simultaneous
peaks of these predator populations, the rapidly developing
aphid population reached a plateau apparently because predation
coupled with wasp parasitism were nearly equal to aphid
reproduction. Lady beetle larvae continued the predation
pressure and the aphid population declined dramatically along
with the adult lady beetles and lacewing and syrphid larvae. In
this case it is difficult to determine whether an insecticide should
be used when the aphid infestation becomes severe or whether a
farmer could monitor the natural enemy populations to deter-
mine if they will be effective in controlling the aphids.
 Augmentation of the natural enemy population with releases
of predators (especially lacewings and lady beetles) or perhaps
with parasites when the plants have low to moderate aphid
populations may make insecticide application to asparagus beans
unnecessary. The cost to purchase and apply these natural control
agents, if a source were available, would need to be competitive
with insecticide costs. In addition, encouraging non-pest aphid
species that are specific to plants that border the crop fields would
help maintain higher endemic populations of predators and
parasites that may in turn respond more efficiently to aphid in-
festation of a crop. A survey of the aphid species on local weed
and non-weed plants may be useful in determining what host
plants to seed in border areas or as intercrops. The development
and dissemination of simple, practical methods such as these for
the small farmer are needed. In a recent review, Matteson et al.
(1984) deal with the problems of pest management in small farm-
ing systems and conclude that traditional cropping practices often
supply a basis for improved pest control that can be adapted to
the existing socioeconomic conditions.


Acknowledgements
 The following research entomologists of the Systematic Entomology Laboratory,
U.S.D.A., identified specimens for this study: J.P. Kramer (Cicadellidae), M.B.
Stoetzel (Aphididae), P.M. Marsh (Braconidae), E. Grissell (Chalcididae), M.E.
Schauff (Eulophidae), D.R. Smith (Formicidae), F.C. Thompson (Syrphidae), and
D. Wilder (Tachinidae). H. Townes, American Entomological Institute, and C.
Dasch, Muskingum College, identified the ichneumon wasps.





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