March/April 2023 - 16

PEST MANAGEMENT
A growing
problem
Leaffooted plant bugs posing
bigger threat to tree nuts
BY CRYSTAL NAY
CONTRIBUTING WRITER
couple of species of leaffooted plant bugs are
commonly found in California tree nuts, Leptoglossus
zonatus and Leptoglasses clypealis. Historically, they
have not been that big of a problem, at least not in comparison
to other pressures that growers face.
A
During the last decade, however, there has been an
increase in reports of damage by leaffooted plant bugs, and
now it is becoming an issue.
From crop to crop
Broadly speaking, in California, these insects overwinter as
adults in large aggregations, typically in sheltered locations, such
as riparian habitats, residential areas, brush piles or citrus. When
it gets warmer in the spring, and days get longer again, they move
into native vegetation. As nuts and fruit develop, they colonize
nut orchards and other crops such as pomegranates.
They feed by inserting their tube-like mouthparts into
plant tissues and inject saliva, which helps break down the
tissue, and they suck up the resulting liquid. The nutrientrich
developing almonds provide a good food source. The
insects feed until the shells start to harden and become more
difficult to penetrate.
Then the insects move on to the next crop. These bugs
will feed on pistachio, roughly around June, until the same
sequence of events occurs: the shell hardens, and the insects
cannot penetrate it to feed.
Photos: Dr. Sean Halloran,
Department of Entomology,
University of California
16 MARCH/APRIL 2023
The insects then move on to the next crop: pomegranate,
where they will likely finish out the season before returning
to overwintering in large aggregations.
Researchers at University of California-Riverside's
Department of Entomology and European collaborators have
been researching the chemical signals used by leaffooted
plant bugs, specifically the species Leptoglossus zonatus and
Leptoglossus occidentalis.

March/April 2023

Table of Contents for the Digital Edition of March/April 2023

March/April 2023 - 1
March/April 2023 - 2
March/April 2023 - 3
March/April 2023 - 4
March/April 2023 - 5
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https://www.nxtbook.com/greatamericanmediaservices/NNG/march-april-2024
https://www.nxtbook.com/greatamericanmediaservices/NNG/january-february-2024
https://www.nxtbook.com/greatamericanmediaservices/NNG/november-december-2023
https://www.nxtbook.com/greatamericanmediaservices/NNG/september-october-2023
https://www.nxtbook.com/greatamericanmediaservices/NNG/july-august-2023
https://www.nxtbook.com/greatamericanmediaservices/NNG/may-june-2023
https://www.nxtbook.com/greatamericanmediaservices/NNG/march-april-2023
https://www.nxtbook.com/greatamericanmediaservices/NNG/january-february-2023
https://www.nxtbook.com/greatamericanmediaservices/NNG/november-december-2022
https://www.nxtbook.com/greatamericanmediaservices/NNG/september-october-2022
https://www.nxtbook.com/greatamericanmediaservices/NNG/july-august-2022
https://www.nxtbook.com/greatamericanmediaservices/NNG/may-june-2022
https://www.nxtbook.com/greatamericanmediaservices/NNG/march-april-2022
https://www.nxtbook.com/greatamericanmediaservices/NNG/january-february-2022
https://www.nxtbook.com/greatamericanmediaservices/NNG/winter-2022
https://www.nxtbook.com/greatamericanmediaservices/NNG/fall-2021
https://www.nxtbook.com/greatamericanmediaservices/NNG/summer-2021
https://www.nxtbook.com/greatamericanmediaservices/NNG/winter-2021
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