Organic Farmer October/November 2019

Continued from Page 18
times the cost of using any mating disruption
product. In hindsight across all
research sites, the cost of mating disruption
exceeded the return on investment
if damage without mating disruption
was under 1 percent, broke even if
damage was around 1.5 to 2 percent,
and very quickly turned into a positive
return on investment any time damage
exceeded 2 percent.
Organic growers considering mating
disruption should develop their own
cost-benefit analysis. This is especially
true considering that organic almond
orchards typically have reduced yields,
but higher per-pound prices than the
previous example. Growers should
also consider other benefits of mating
disruption, such as increased crop
exportability due to decreased risk
of aflatoxins, increased ability to sell
in-shell nuts, or the value of marketing
the sustainability of production
practices.
Individual Orchard Conditions
Individual orchard conditions should
also be considered when determining
the fit for a mating disruption system.
This includes the size and orientation
of the orchard as well as the surrounding
landscape. Effective mating disruption
assumes that a solid plume of pheromone
can be maintained within the
orchard. This means that when implementing
mating disruption, bigger is
better. Efficacy is also increased when
orchards are shaped like squares or rectangles.
Efficacy is reduced as orchards
become longer and skinnier, especially
in areas known for high winds that can
blow pheromone off-site.
Orientation of the orchard within the
landscape should also be considered.
This is especially true because mating
Aerosol mating disruption dispenser. Photo
courtesy of Pacific Biocontrol Corporation.
disruption cannot control gravid
moths that fly into the orchard after
mating elsewhere. Mating disruption
works best when the surrounding
landscape does not contain navel
orangeworm hosts, or where the
neighboring growers have effective
sanitation and spray programs. The
ability of navel orangeworm to move
back and forth among neighboring
orchards makes communication with
neighbors essential when trying to
control this pest at a landscape scale. In
an ideal situation, the organic grower
using mating disruption would be
surrounded by neighbors who are also
using mating disruption to contribute
to an even larger, contiguous pheromone
plume.
For more information on mating disruption,
consult with the University of
California Integrated Pest Management
Guidelines found at the UC IPM Web
site (http://ipm.ucanr.edu). Once at
the site, click on Agricultural Pests,
followed by Almonds, Pistachios or
Walnuts. Additional information can
also be provided by your local UC
Cooperative Extension Farm Advisor.
Comments about this article? We want
to hear from you. Feel free to email us at
article@jcsmarketinginc.com
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Organic Farmer October/November 2019