August 2023 - 29

GRAPES
time the brown " scorched " leaves indicate the pest has
been in the area, the plant has already been infected for
a year.
" So we've got vines that are infected in the summer,
asymptomatic in the fall, sitting with the disease all
winter and carrying the disease the next summer when
sharphshooters are spreading it to new vines, " Haviland
said. " Then after that's already occurred, we can see the
symptoms and pull (vines) out. "
Citrus trees are popular GWSS hosts but they and
the fruit aren't affected. It's not uncommon, however,
for citrus and grape crops to be in the same area in
California. GWSS adults, which are large for leafhoppers,
are highly mobile and often move between adjacent
orchards and vineyards throughout the day.
" You treat one orchard, they'll fly to a vineyard and then
fly back later, " Haviland said. " It takes a huge industry
coordination. In some areas, all of them (growers) treat
at the same time. Once the movement to grapes start,
typically all growers are applying neonicotinoids for vine
mealybugs as well as glassy-winged sharpshooters and
leafhoppers, so it's three birds with one stone. "
That cooperation between growers, as well as
homeowners who let agents from the state spray trees
and vines in their yards, is one part of California's push to
control GWSS/Pierce's disease. Government programs
that pay for citrus spraying (because GWSS don't kill
citrus, there's no incentive for growers to treat their
groves), traps, surveys and Pierce's disease tracking are
also necessary.
Although a California program releases parasitoid
wasps that attack GWSS eggs, the sharpshooters are hard
to propagate to supply eggs for a breeding program, and
those programs are focused more on urban areas and
not commercial production areas. Because there aren't
pheromones available to attract the GWSS, sticky traps
(the ubiquitous yellow cards) are useful in detecting their
presence, but not as a means to control the population.
The traps should be placed in quarter-mile grids to
chart the pest's movement, Haviland said.
Haviland encourages Washington growers to be vigilant
for signs of Pierce's disease and rely on experts with UC's
Cooperative Extension and California Department of Food
and Agriculture programs for information.
" We are never going to get rid of Xylella and we're never
going to get rid of these sharpshooters where they are
established, " he said. " The exceptions are in satellite
areas, urban areas. Yes, we have had lots of successful
eradications, but once it's in commercial (production)
areas, that's not going to happen. "
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August 2023

Table of Contents for the Digital Edition of August 2023

Editor's Letter
Grower Profile: Keeping it clean
Biocontrols: Salinas Biological Summit
Organic Grower
Ag Tech: Drone assignment
Grapes: A piercing problem
Great Lakes EXPO News: Connecting growers through the digital market space
Plant & Soil Health: A strawberry threat
Farm Market & Agritourism: The first step is knowing who your customers are
CMI
Ag Labor Review
Classifieds
Advertiser Index
August 2023 - 1
August 2023 - 2
August 2023 - 3
August 2023 - Editor's Letter
August 2023 - 5
August 2023 - Grower Profile: Keeping it clean
August 2023 - 7
August 2023 - 8
August 2023 - 9
August 2023 - Biocontrols: Salinas Biological Summit
August 2023 - 11
August 2023 - 12
August 2023 - Organic Grower
August 2023 - 14
August 2023 - 15
August 2023 - 16
August 2023 - 17
August 2023 - 18
August 2023 - 19
August 2023 - 20
August 2023 - 21
August 2023 - 22
August 2023 - 23
August 2023 - 24
August 2023 - Ag Tech: Drone assignment
August 2023 - 26
August 2023 - 27
August 2023 - Grapes: A piercing problem
August 2023 - 29
August 2023 - Great Lakes EXPO News: Connecting growers through the digital market space
August 2023 - 31
August 2023 - Plant & Soil Health: A strawberry threat
August 2023 - 33
August 2023 - Farm Market & Agritourism: The first step is knowing who your customers are
August 2023 - 35
August 2023 - CMI
August 2023 - 37
August 2023 - Ag Labor Review
August 2023 - 39
August 2023 - Classifieds
August 2023 - 41
August 2023 - Advertiser Index
August 2023 - 43
August 2023 - 44
https://www.nxtbook.com/greatamericanmediaservices/FGN/december-2024
https://www.nxtbook.com/greatamericanmediaservices/FGN/2025-fruit-nut-growers-buyers-guide
https://www.nxtbook.com/greatamericanmediaservices/FGN/november-2024
https://www.nxtbook.com/greatamericanmediaservices/FGN/october-2024
https://www.nxtbook.com/greatamericanmediaservices/FGN/september-2024
https://www.nxtbook.com/greatamericanmediaservices/FGN/august-2024
https://www.nxtbook.com/greatamericanmediaservices/FGN/july-2024
https://www.nxtbook.com/greatamericanmediaservices/FGN/june-2024
https://www.nxtbook.com/greatamericanmediaservices/FGN/may-2024
https://www.nxtbook.com/greatamericanmediaservices/FGN/april-2024
https://www.nxtbook.com/greatamericanmediaservices/FGN/march-2024
https://www.nxtbook.com/greatamericanmediaservices/FGN/february-2024
https://www.nxtbook.com/greatamericanmediaservices/FGN/january-2024
https://www.nxtbook.com/greatamericanmediaservices/FGN/december-fgn
https://www.nxtbook.com/greatamericanmediaservices/FGN/fgn-vgn-40-under-40-class-of-2023
https://www.nxtbook.com/greatamericanmediaservices/FGN/buyers-guide-2024
https://www.nxtbook.com/greatamericanmediaservices/FGN/november-2023
https://www.nxtbook.com/greatamericanmediaservices/FGN/october-2023
https://www.nxtbook.com/greatamericanmediaservices/FGN/september-2023
https://www.nxtbook.com/greatamericanmediaservices/FGN/august-2023
https://www.nxtbook.com/greatamericanmediaservices/FGN/july-2023
https://www.nxtbook.com/greatamericanmediaservices/FGN/june-2023
https://www.nxtbook.com/greatamericanmediaservices/FGN/may-2023
https://www.nxtbook.com/greatamericanmediaservices/FGN/april-2023
https://www.nxtbook.com/greatamericanmediaservices/FGN/march-2023
https://www.nxtbook.com/greatamericanmediaservices/FGN/february-2023
https://www.nxtbook.com/greatamericanmediaservices/FGN/january-2023
https://www.nxtbook.com/greatamericanmediaservices/FGN/december-2022
https://www.nxtbook.com/greatamericanmediaservices/FGN/november-2022
https://www.nxtbook.com/greatamericanmediaservices/FGN/buyers-guide
https://www.nxtbook.com/greatamericanmediaservices/FGN/october-2022
https://www.nxtbook.com/greatamericanmediaservices/FGN/september-2022
https://www.nxtbook.com/greatamericanmediaservices/FGN/august-2022
https://www.nxtbook.com/greatamericanmediaservices/FGN/july-2022
https://www.nxtbook.com/greatamericanmediaservices/FGN/june-2022
https://www.nxtbook.com/greatamericanmediaservices/FGN/may-2022
https://www.nxtbook.com/greatamericanmediaservices/FGN/april-2022
https://www.nxtbook.com/greatamericanmediaservices/FGN/march-2022
https://www.nxtbook.com/greatamericanmediaservices/FGN/february-2022
https://www.nxtbook.com/greatamericanmediaservices/FGN/buyersguide-2022
https://www.nxtbook.com/greatamericanmediaservices/FGN/january-2022
https://www.nxtbook.com/greatamericanmediaservices/FGN/december-2021
https://www.nxtbook.com/greatamericanmediaservices/FGN/november-2021
https://www.nxtbook.com/greatamericanmediaservices/FGN/october-2021
https://www.nxtbook.com/greatamericanmediaservices/FGN/september-2021
https://www.nxtbook.com/greatamericanmediaservices/FGN/august-2021
https://www.nxtbook.com/greatamericanmediaservices/FGN/july-2021
https://www.nxtbook.com/greatamericanmediaservices/FGN/june-2021
https://www.nxtbook.com/greatamericanmediaservices/FGN/may-2021
https://www.nxtbook.com/greatamericanmediaservices/FGN/april-2021
https://www.nxtbook.com/greatamericanmediaservices/FGN/march-2021
https://www.nxtbook.com/greatamericanmediaservices/FGN/february-2021
https://www.nxtbook.com/greatamericanmediaservices/FGN/buyersguide-2021
https://www.nxtbook.com/greatamericanmediaservices/FGN/january-2021
https://www.nxtbook.com/greatamericanmediaservices/FGN/december-2020
https://www.nxtbook.com/greatamericanmediaservices/FGN/november-2020
https://www.nxtbook.com/greatamericanmediaservices/FGN/october-2020
https://www.nxtbook.com/greatamericanmediaservices/FGN/september-2020
https://www.nxtbook.com/greatamericanmediaservices/FGN/august-2020
https://www.nxtbook.com/greatamericanmediaservices/FGN/july-2020
https://www.nxtbook.com/greatamericanmediaservices/FGN/june-2020
https://www.nxtbook.com/greatamericanmediaservices/FGN/may-2020
https://www.nxtbook.com/greatamericanmediaservices/FGN/april-2020
https://www.nxtbook.com/greatamericanmediaservices/FGN/march-2020
https://www.nxtbook.com/greatamericanmediaservices/FGN/february-2020
https://www.nxtbook.com/greatamericanmediaservices/FGN/buyersguide-2020
https://www.nxtbook.com/greatamericanmediaservices/FGN/january-2020
https://www.nxtbook.com/greatamericanmediaservices/FGN/december-2019
https://www.nxtbook.com/greatamericanmediaservices/FGN/november-2019
https://www.nxtbook.com/greatamericanmediaservices/FGN/october-2019
https://www.nxtbook.com/greatamericanmediaservices/FGN/september-2019
https://www.nxtbook.com/greatamericanmediaservices/FGN/august-2019
https://www.nxtbook.com/greatamericanmediaservices/FGN/july-2019
https://www.nxtbook.com/greatamericanmediaservices/FGN/june-2019
https://www.nxtbook.com/greatamericanmediaservices/FGN/may-2019
https://www.nxtbook.com/greatamericanmediaservices/FGN/april-2019
https://www.nxtbook.com/greatamericanmediaservices/FGN/march-2019
https://www.nxtbook.com/greatamericanmediaservices/FGN/february-2019
https://www.nxtbook.com/greatamericanmediaservices/FGN/january-2019
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