in Riparian Buffers
Over a three-year
period, a team of researchers led by Doug
Walsh, Tim Waters, and
Ron Wight from the
Irrigated Agriculture Research and Extension Center (IAREC) in Prosser
investigated the arthropod populations in a variety of riparian
areas in the Yakima Valley. Specifically, the team studied the relationship
between different vegetation regimes and the presence of both pest
and beneficial arthropods. Plant diversity was categorized as pristine
(primarily native plant), rehabilitated (replanted with primarily
native plant species), or weedy (invaded by exotic weed species).
In the lower
Yakima valley, riparian buffers are often near agricultural areas.
The research team hypothesized that arthropods in these buffers
could migrate into the adjacent agricultural areas and contribute—for
better or worse—to the arthropod fauna within the crop system.
The results indicated that riparian areas consisting of invasive
flowering broadleaf weeds hosted significantly more pest arthropods
than the riparian areas that were maintained in a more pristine
condition with a greater number of native plants. In addition, beneficial
arthropods were seen to thrive in the more stable native environments.
have implications for buffer rehabilitation planning and implementation.
Choosing native plant species creates a habitat less likely to harbor
pest arthropods that could potentially migrate into adjacent agroecosystems
and inflict damage to crops. Fewer pests migrating into the adjacent
agroecosystem translates into fewer pesticide applications by farmers
and a safer, healthier environment. This integration of weed management
and insect management is a classic example of using IPM to protect
both crops and the environment.
Walsh, D. B.,
and R. P. Wight. 2000. Riparian
Buffer Zones: Summer 2000 Field Study Results. Agrichemial
and Environmental News. Issue No. 175, November 2000.
Walsh, D. B.
of Buffer Zones on Agricultural Lands: Impacts on Beneficial and
Pest Organisms. Agrichemial and Environmental News.
Issue No. 163, November 1999.