2022 Quarter 2 Newsletter

Close-up of several onion stalks in a field. They are green with yellow patches.

Staying Alert to Onion and Potato IPM

Regional Vegetable Specialist Tim Waters and colleagues Carrie Wohleb and Lindsey du Toit released two editions of their Onion Alert e-newsletter in June. The June 10 edition provided insight on downy mildew (DM), which was anticipated to be an issue in onion this year due to an unusually wet and cool spring, and reminded growers to scout for and proactively manage thrips. The June 27 edition confirmed the presence of DM in the region and provided information on scouting for and reporting it. It detailed the causal agent of the disease, symptoms and signs of the infection and associated secondary infections, and an overview of managing DM in onion production, including an expanded list of fungicides and advice on rotation to forestall fungicide resistance.

Waters also contributed to the region’s Potato Alert e-newsletter. Seven editions have been released already this growing season, with topics including the latest population dynamics on potato psyllids, beet leafhoppers, aphids, Lygus, and Colorado potato beetles.

Waters also helped spearhead an interactive and hands-on IPM workshop for potato growers and field scouts on June 15 and participated in the WSU Potato Research Group’s potato field day on June 23, where he spoke about Control of Colorado Potato Beetle.

Small oval insect with inset of man speaking

Wine Grape, Mint, Alfalfa Seed, and Hop Outreach

Washington State IPM Coordinator and Extension Entomologist Doug Walsh joined Extension Viticulturist Michelle Moyer in a presentation and panel discussion on grape phylloxera in April as part of the Washington Advancements in Viticulture and Enology (WAVE) educational outreach series sponsored by the Washington State Wine Commission.

Walsh conducted in-person field days in both mint and alfalfa grown for seed this quarter. The alfalfa seed event, held in Touchet, was attended by Derek Sandison, Director of the Washington State Department of Agriculture. Attendees had a productive discussion on the pest management needs of this important seed crop given the revocation of the tolerance for chlorpyrifos on alfalfa.

On behalf of The IR-4 Project, Walsh hosted a Hops Virtual Tour for the US Environmental Protection Agency and other interested parties. Approximately 180 attended this online event in April.

Also in April, Walsh presented at the Pacific Branch Entomological Society of America meeting in Santa Rosa, CA. He moderated a session on Biology, Monitoring, and Management of Disease Vectors in West Coast Vineyards, in which he also presented on grape mealybug. Walsh also presented Insecticide Resistance Management in Specialty Crops in the Yakima Valley and co-authored another presentation on insecticide resistance given by former graduate student Adekunle Adesanya. Current graduate student Stephen Onayemi presented on their grape mealybug mating disruption studies.

A group listening to a presentation in a green field with signs and flags

New Pubs, Field Day, Podcasts and More for Wheat Growers

Small Grains Extension Specialist Drew Lyon released an updated version of Integrated Management of Mayweed Chamomile in Wheat and Pulse Crop Production Systems in May. This publication, co-authored by Ian Burke, Andy Hulting, and Joan Campbell, presents an integrated approach to sustainable, long-term control of this troublesome weed species.

Lyon also organized the WSU Weed Science Field Tour, held on June 8. The first in-person weed science field tour since 2019, the event included discussions on:

  • Broadleaf weed control in winter wheat
  • Italian ryegrass control in spring canola
  • Italian ryegrass control in spring wheat and chickpea
  • Monitoring weed seed banks

As usual, the WSU Wheat & Small Grains website added a wealth of articles and resources this quarter. Lyon’s Wheat Beat Podcasts included IPM-related episodes describing The Latest on Snow Mold Research with Savannah Phipps and Stem Rust Research with Arjun Upadhaya, both with WSU’s Department of Crop and Soil Sciences. And the Weeders of the West Blog included posts on:

  • Aggressor (Quizalofop) Herbicide Application Timing by Oregon State University’s Judit Barroso
  • The Reemergence of Preemergence Herbicides by Lyon
  • Watch Out for Palmer Amaranth in the Pacific Northwest by OSU’s Joel Felix
  • Looking Critically at Harvest Weed Seed Control: What Benefits Can Be Realized in PNW Dryland Cropping Systems? by University of Idaho’s Doug Finkelnburg
Cover of the field guide shows grapes and grape pests

Updated and Expanded Grape IPM Guide Now Available

Research and Extension Communication Specialist Sally O’Neal and fellow Extension IPM team member Michelle Moyer announced the release of the Field Guide for Integrated Pest Management in Pacific Northwest Vineyards, Second Edition. The first edition, also edited by Moyer and O’Neal, was released in 2013 and has since become the go-to reference for Pacific Northwest grape growers and field staff.

The guide contains an introduction to IPM principles and pesticide safety, discusses resistance management, and includes a section on the interaction of various viticulture practices with IPM. Separate photo-filled sections are devoted to insect and mite management, beneficial arthropods (their importance in IPM, monitoring them, and pesticide compatibility), disease management, nematode management, and weed management. A final section illustrates and describes abiotic stresses and disorders as well as nutrient deficiencies and toxicities that can be mistaken for pest damage. This section also includes an expanded discussion and illustration of vertebrate damage in PNW vineyards.  

The guide drew on the expertise and photo libraries of dozens of scientists in Washington, Oregon, Idaho, and California. It includes updated pest management practices for established pests, expanded sections for pests of increasing importance (e.g., spider mites, phylloxera, esca, young vine decline), and new information on emerging pests and diseases (e.g., blister mites, leaffolders, spotted lanternfly, red blotch).

Worm-like creatures crawling around on a vegetable root ball

Small Farm Outreach on Downy Mildew, Millipedes

Regional Horticulture and IPM Specialist Laurel Moulton hosted a Dirt Talk session in April. Dirt Talk is a farmer-to-farmer networking and learning series presented by WSU Regional Small Farms Program in which program staff collaborate with a local farmer willing to share expertise on a given topic. Moulton and Scott Chichester, owner of Chi’s Farm in Sequim, shared helpful information on identification and management of downy mildew. Chichester’s expertise on downy mildew in basil and spinach under greenhouse/high tunnel conditions provided an important perspective on this fungal disease while Moulton moderated the interactive discussion with attendees and discussed resources available through WSU to help small farm owners with integrated pest and disease management.

Moulton also recently published an article on millipedes. Entitled Sometimes it isn’t what it seems (pdf), this article was co-authored by WSU Plant Diagnostician Jenny Glass. Millipedes are segmented, tube-shaped arthropods (not insects), with two legs per segment, hence their name, derived from the Latin for “many feet.” Since their preferred diet is rotting material, they have typically been a problem only as a secondary pest in combination with other species (e.g., root maggots, slugs, wireworms). Moulton and Glass’s article outlines the life cycle of millipedes, discusses their occasional status as a primary pest, and provides non-chemical IPM tactics for monitoring, discouraging, and managing millipedes. This article and other resources are available on the Pests & Plant Disease subpage of the Small Farms website.

Newsletter cover shows 4 photos of plastic mulch in a small farm setting.

Biodegradable Mulch Newsletter Released, Article Published

Vegetable Horticulture Specialist Carol Miles and colleague Lisa DeVetter released the second edition of Sustainable Mulch Management, a free newsletter targeting Extension audiences and those interested in sustainable pest management through the use of agricultural plastic mulches. This newsletter is a joint venture of the WSU Vegetable Horticulture and Small Fruit Horticulture programs. Articles in this edition included:

  • Making the Switch to Soil-Biodegradable Mulches: Lessons Learned from Farmers, by DeVetter and former graduate student Brenda Madrid
  • Building a Better Mulching Industry, a Q & A with agricultural consultant Huan Zhang
  • Introduction to Hydromulch, by graduate student Dakota McFadden
  • An introduction to Miles’ graduate student Srijana Shrestha
  • Information about recent publications and upcoming events

Miles and DeVetter invite interested parties to repurpose the articles in the newsletter for educational use for your own farm or to share with others. This also applies to other information provided on their Plastic Mulches website.

In other plastic mulch news, the American Society for Horticultural Science journal HortTechnology recently published Shrestha and Miles’ article Plastic Mulch and In-row Spacing Effects on Sweetpotato Yield in Northwest Washington, which includes implications for IPM in this crop.

Two women in ball caps and boots examine a grape vine leaf

Newsletter, Webinar, and Boot Camp for Grape Growers

Extension Viticulturist Michelle Moyer edited and released the Spring 2022 Edition (pdf) of Viticulture and Enology Extension News (VEEN), which included articles about management of phylloxera and grape mealybug.

Grape phylloxera was a hot topic this quarter, as Moyer and Extension Entomologist Doug Walsh were asked by the Washington State Wine Commission to present a Phylloxera Update as part of their Washington Advancements in Viticulture and Enology (WAVE) educational outreach series. Topics for this April webinar included how to use the Phylloxera Risk Assessment map, how to sample for phylloxera, and options to manage infestations.

Also this quarter, Moyer organized and conducted the popular Viticulture Intern Boot Camp, an all-day workshop designed to provide a baseline level of knowledge to individuals employed in a Washington State vineyard or allied field. The May 24 workshop included both classroom and in-field training on:

  • Understanding a grape growing season
  • Pest and disease scouting
  • Cold damage and yield estimation
  • Identifying nutrient disorders and understanding fertilization
  • Organizing and planning a productive internship experience

Participants took away valuable hands-on experience as well as reference materials including the hot-off-the-press second edition of the Field Guide for Integrated Pest Management in Pacific Northwest Vineyards. For more information on this guide, see 4th article in this newsletter.

Fly with large red eyes dropping eggs on the skin of a fruit

Nationwide SWD Group Reviews Progress, Charts Course

Tree Fruit IPM Extension Specialist Betsy Beers and WSU colleague Tobin Northfield are co-PIs on a nationwide Sustainable Spotted Wing Drosophila Management project funded by the USDA NIFA Specialty Crop Research Initiative. Northfield serves as Washington State lead on this project, which seeks to advance the development of sustainable, integrated management strategies for spotted wing drosophila, SWD, based on biology. The project team held an outreach meeting with its stakeholder advisory group on April 27 via Zoom. The advisory group includes researchers, regulators, farm advisors, industry representatives, growers, and agronomists impacted by SWD.

Co-presented by WSU Extension Specialist Gwen Hoheisel and postdoctoral researcher Dylan Beal from the Beers lab, the meeting included a slide show summarizing past, ongoing, and proposed research by the entire SCRI group, which includes participants from University of Georgia, Washington State University, University of California at Davis, Cornell University, Rutgers University, University of California at Berkeley, Oregon State University, University of Maine, Michigan State University, North Carolina State University, University of California Agriculture and Natural Resources, and USDA-ARS.

Stakeholder attendees were surveyed (via real-time Qualtrics) as to which projects / subobjectives were most important to them. The resulting 4 objectives will be the focus of the team’s ongoing efforts:

  1. Chemical control and resistance management
  2. Behavioral controls including baits/attracticides
  3. Refining monitoring of blueberries to determine infestation levels
  4. Rearing/release of the Asian parasitoid, Ganaspis brasiliensis
11 winged insects with largest, Asian giant hornet, in the middle

Exotic Hornet ID Training

Urban IPM Coordinator Carrie Foss partnered with Cassie Cichorz (pdf), Outreach and Education Specialist at the Washington State Department of Agriculture, on an Exotic Hornet Identification Workshop held May 19 and 26.

The featured speaker on May 19 was WSU Entomologist Elizabeth Murray, who presented on taxonomic relationships between insects in general, with an emphasis on groups of insects confused with hornets such as wasps and bees. This first day’s session ended with practicing identification of the species of concern.

The May 26 session included WSDA presenters Cichorz, Jessica La Belle, and Robert Ambriz presenting on a variety of topics including detecting and responding to falsified submissions of giant hornet sightings, deescalating a concerned citizen, and using the North American Hornet Screening Tool. Cichorz was joined by USDA Entomologist Chris Looney in a second session where participants practiced identification. Dr. Looney manages the WSDA’s Olympia Entomology Laboratory, providing identification services for Washington stakeholders, supporting exotic pest surveys, and conducting research on exotic insect species.

An audience of 114 registered for the two-day workshop. All were given the information and tools needed to be an informed citizen scientist and report an Asian giant hornet sighting via the WSDA reporting web page.

(Ed. Note: Outreach in this newsletter took place prior to June 30, 2022. On July 25, the Entomological Society of America announced “northern giant hornet” as the official common name for Vespa mandarinia, previously known colloquially as “Asian giant hornet.”)

hornet’s face, title of new publication, and photo of a hornet and a honey bee facing one another

Helping Beekeepers Understand Asian Giant Hornets

While Urban IPM Coordinator Foss was educating Washington State citizens and agency representatives about Asian giant hornets (above), Honey Bee Health Specialist Brandon Hopkins and his team were conducting Asian giant hornet (AGH) outreach to our state’s beekeepers. Hopkins and postdoctoral researcher Kelly Kulhanek wrote and published Distinguishing Asian Giant Hornet Damage to Honey Bee Colonies (pdf) to help beekeepers (especially those in northwestern Washington and adjacent British Columbia) determine whether this exotic species has been a problem in their hives.

The 4-page publication, WSU Extension Fact Sheet FS370E, provides an introduction to AGH, which first appeared in Washington State in 2019, and information on how this exotic pest might prove harmful to commercially reared European honey bees, the variety kept in the United States. This publication outlines the 3 distinct phases of AGH predation on hives (hunting, slaughter, and occupation), and provides detailed descriptions of each phase, as well as how the damage differs from pesticide kills or rodent predation. The fact sheet also offers a decision tree schematic to help determine whether hive damage should be attributed to AGH and, if so, how to report it.

(Ed. Note: Outreach in this newsletter took place prior to June 30, 2022. On July 25, the Entomological Society of America announced “northern giant hornet” as the official common name for Vespa mandarinia, previously known colloquially as “Asian giant hornet.”)