PestFacts WA

Final PestFacts WA newsletter for 2022!

A combine harvester harvesting wheat
Harvesting wheat. Photo courtesy of DPIRD.

This is the 21st and final issue of the PestFacts WA newsletter for the 2022 growing season. Extra editions may be circulated if extraordinary circumstances occur after this time.

All of this season’s PestFacts WA newsletters can be found at DPIRD’s PestFacts WA newsletter archive.

2022 PestFacts WA statistics

This year the PestFacts WA team received almost 3,100 reports in total (current to 9 November 2022).

What were the top five reported pests?

The PestFacts WA team received 1,135 invertebrate pest reports. The native budworm was the most reported pest with 416 reports received via the spring trapping program and non-trapping reports. This was followed by the diamondback moth (231) and redlegged earth mite (139). The top five insects reported are listed in Table 1, below.

Table 1 The top five pests and number of reports to the PestFacts WA service during 2022.
Insect Number of reports
Native budworm - trapping and non-trapping reports 416
Diamondback moth 231
Redlegged earth mite 139
Russian wheat aphid 48
Green peach aphid 43










What were the top five reported plant diseases for 2022?

As of 9 November 2022, there were 706 plant disease reports recorded by the PestFacts WA team from a variety of sources. Powdery mildew in wheat was the most reported disease (147 reports), followed by Blackleg in canola (95). Table 2, below, displays the other diseases that were most commonly reported.

Table 2 The top plant diseases and number of reports to the PestFacts WA service during 2022.
Disease Number of reports
Powdery mildew in wheat 147
Blackleg in canola 95
Spot-type net blotch of barley 79
Septoria nodorum blotch in wheat 57
Sclerotinia stem rot in canola 39










2022 PestFacts WA map statistics

The PestFacts WA map displaying occurrences for all disorders reported for the previous two weeks, current to 18 November 2022. Map courtesy of DPIRD.
PestFacts WA map displaying occurrences for all disorders reported for the previous two weeks, current to 18 November 2022. Map courtesy of DPIRD.

The PestFacts WA map provides a visual display of the pests and diseases reported by the industry since 1996. Viewers can choose a host, a disorder and a time period. They can also select a 'Same time as last year' map view to highlight seasonal commonality or differences.

In 2022, an impressive 6,979 maps were generated as of 15 November. This number includes every map generated between each dropdown box selection.

Maps that displayed ‘All’ disorders were generated the most with 4,741 generated.

Russian wheat aphid was the disorder map most specifically generated (499), followed by Diamondback moth maps (245). To see what the other top disorder maps viewed were refer to Table 3 below. These disorders may have been viewed for previous season’s distribution (historical data) as well as this season.

Table 3 The most popular PestFacts WA disorder maps (disease, insects and other) viewed in 2022.
Disorder Number of maps generated
Russian wheat aphid 499
Diamondback moth 245
Sclerotinia stem rot 209
Powdery mildew 175
Native budworm 148












The PestFacts WA team would like to say a big thank you to everyone who took the time to submit insect, plant disease reports and identification requests this year to the PestFacts WA service.

We would also like to acknowledge the following people and projects for sharing their invertebrate and/or plant disease reports;

  • Consenting clients using the Agworld and Back Paddock Adviser apps. For more information on this collaboration refer to the 2022 PestFacts WA Issue 21 article PestFacts WA continues successful collaboration with Agworld and Back Paddock
  • DPIRD and GRDC co-funded project titled: Disease surveillance and related diagnostics for the Australian grain industry (Western region)
  • DPIRD, GRDC & SARDI co-funded project titled: Survey of the Summer/Autumn Brassica Refuges for Diamondback Moth in the Western Region to Predict Early Season Risk of Infestation
  • DPIRD’s subproject in the national Hort Innovation-led project: iMapPESTS, Sentinel surveillance for agriculture
  • DPIRD Boosting Grains Science Partnership surveillance project for Green peach aphid surveillance data.

All reports are greatly appreciated and are vital for PestFacts WA to keep growers and consultants informed and up to date with what is happening across WA.


For more information on the PestFacts WA service please contact PestFacts WA newsletter editor Cindy Webster, Narrogin on +61 (0)8 9881 0201.



Article author: Cindy Webster (DPIRD Narrogin).

Green bridge management over summer

Volunteer cereals forming a green bridge in a paddock
Volunteer cereal plants forming a green bridge. Photo courtesy of DPIRD.

Growers need to consider potential disease carryover into the 2023 season if wet conditions are experienced during summer resulting in weed and crop regrowth. This vegetation can serve as a ‘green bridge’ for diseases and pests which need a living plant to survive, such as cereal rusts and powdery mildew, root diseases and aphids. If weeds and/or volunteers are present at the start of the new cropping season, particularly in or adjacent to cropping paddocks, there is a greater risk of early spread of pests, viruses and diseases to newly emerging crops.

Rust spores are wind dispersed and can easily spread from one end of the grainbelt to the other. This year, wheat powdery mildew was prevalent across the wheatbelt and wheat leaf rust in many parts of the Geraldton port zone. If there is a wet summer and autumn in 2023 then inoculum of these diseases may be carried into the new cropping season.

Disease management strategies for 2023

To minimise this risk growers are encouraged to monitor:

  • This year’s crops before harvest to see what diseases are present
  • Any green bridge that is present in summer and autumn for disease, so that timely action can be taken to identify the pathogen and limit the spread and build-up of inoculum.

It is crucial that growers eradicate weeds and crop volunteers, including those along fence lines, prior to the start of the cropping program to reduce potential pest and disease outbreaks.

Ideally there needs to be a break (a fallow period) of at least two weeks free of vegetation capable of hosting disease or pests prior to sowing. To achieve this the weeds and volunteers should be sprayed with a herbicide at least four to six weeks before sowing, to ensure weeds are completely dead at planting.

Alternatives to herbicides are to heavily graze or cultivate weeds and crop volunteers which will reduce their potential as a ‘green bridge’ or host of diseases and pests.

When managing the green bridge growers need to consider retaining at least 50% ground cover to reduce the risk of erosion during crop establishment. Especially on susceptible soils that are prone to erosion.

In addition to managing the green bridge growers can;

•           Sow clean seed. Use certified seed treated with seed dressing fungicide that provides protection from at least smuts and bunts. Seed can be tested for fungal pathogens and virus infection through the Department’s Diagnostic Laboratory Services – Plant pathology services.

•           Know the latest disease ratings of your varieties and plan accordingly. Use adult plant resistant varieties. The 2023 WA Crop Sowing Guide is available on the DPIRD website, which details the disease susceptibility for each variety.

•           Consider applying in-furrow or seed dressing fungicides to reduce your risk of early infection of diseases such as rusts, net blotches and powdery mildew in susceptible varieties, and rhizoctonia, crown rot and take-all.  For more information see the Department's Seed dressing and in-furrow fungicides for cereals in Western Australia.

•           In case of early disease outbreak, budget for early foliar fungicide sprays where upfront fungicides are not used. For more information visit the department's Registered foliar fungicides for cereals in Western Australia.

•           Reduce exposure to stubble borne diseases through rotation and careful paddock planning (to avoid sowing on or adjacent to infected stubble) or stubble management (such as grazing, windrowing, baling, incorporating or burning).

•           Earlier sown crops may be more at risk of some foliar diseases such as powdery mildew, net blotches of barley, nodorum blotch and yellow spot of wheat so consider later sowing of susceptible varieties and at risk paddocks, or at least plan to monitor earliest sown paddocks closely for disease.

For more information see the Department's Control of green bridge for pest and disease management and the Grains Research and Development Corporation's (GRDC) Green Bridge fact sheet.

Sclerotinia in lupin and canola

Sclerotinia stem rot in lupins and canola is caused by the same fungus (Sclerotinia sclerotiorum) and both diseases were found across the WA grainbelt in 2022 though at much lower levels than 2021. Sclerotinia can also infect most broad leaf crop and pasture species but not cereals, making them a suitable break crop for the disease.

The disease inoculum, sclerotia, that are not harvested with seed, can survive for up to six years in soil and stubble. Growers are advised to carefully consider paddock rotations and use clean lupin and canola seed in 2023.


For more information on crop diseases contact Plant pathologists Geoff Thomas, South Perth on +61 (0)8 9368 3262, Ciara Beard, Geraldton on +61 (0)8 9956 8504, Andrea Hills, Esperance on +61 (0)8 9083 1144 or Kithsiri Jayasena, Albany on +61 (0)8 9892 8477.  

For more information on crop viruses contact Virologist Benjamin Congdon, South Perth on +61 (0)8 9368 3499.



Article authors: Ciara Beard (DPIRD Geraldton) and Geoff Thomas (DPIRD South Perth).

Article input: Benjamin Congdon (DPIRD South Perth).

PestFacts WA continues successful collaboration with Agworld and Back Paddock


As an alternative method of collecting field data the PestFacts WA team has been successfully collaborating with companies Agworld and Back Paddock, since 2018 and 2019 respectively, to automatically receive pest, disease and weed occurrence reports from their platforms into our database.

The PestFacts WA service relies on the WA grains industry to notify us of the invertebrates and diseases that they are finding in broadacre crops and pastures – whether they know what the insect or disease is or not. In return we provide diagnoses and management advice and alert the grains industry to potential incursions via our PestFacts WA newsletter and other communications. This allows growers and consultants to monitor for specific disorders and respond quickly.

Occurrences are also visually displayed on DPIRD’s PestFacts WA map.

The greater the number of pest, weed and disease reports that DPIRD’s PestFacts WA receives, the more information can be compiled over time to return valuable insights to the WA grains industry.

This reporting system also helps to validate the absence of certain invertebrates, diseases and weeds for Australian grain markets.

The PestFacts WA database is sharing its Application Programming Interface (API) endpoints with Agworld and Back Paddock. For consenting clients, any records entered in the Agworld and Back Paddock Adviser apps that contain pests, weeds or diseases and match a predetermined set of crop/pest/disease combinations are sent as anonymous reports to PestFacts WA.

To address and allay privacy concerns, data is anonymised.

The successful collaboration with Agworld and Back Paddock has seen this season, up to the end of October, a total of 3,799 reports (a combination of weeds, insects, plant disease).

Since beginning this collaboration in 2018, Agworld users have sent more than 6,100 reports (pests, plant diseases and weeds) to the PestFacts WA database. Agworld’s general manager for Australia, Simon Foley, says: “Our aim has been, from the very beginning, to offer a collaborative solution to farmers and their trusted partners. There has been widespread grower adoption which has resulted in large volumes of quality farm data being added to Agworld daily, enabling Agworld and our customers to create these types of synergies for the industry. We firmly believe that this is still only the beginning; the amount of data driven solutions that Agworld can offer to the agricultural sector is really endless”.

Since 2019 Back Paddock Adviser app users have sent almost 3,000 reports in total to the PestFacts WA database. Back Paddock CEO Chris Geeves commented about this collaboration: “We see this collaboration with DPIRD as important for the industry. Sharing aggregated information to enable agronomic advisers and farmers to better track the movement of pests, weeds and diseases, to make better strategic decisions and hopefully reduce the impact on yield, is something we want to be a part of. It’s a further example of the value of digitalisation in agriculture that delivers insights for better farm management, and improved productivity.”

Not all Agworld and Back Paddock reports have been displayed on the PestFacts WA map, but they have assisted the team with gaining a better idea of what pests, plant diseases and weeds were being found across the state by app users.

This collaboration was made possible through a competitive grant process by DPIRD’s eConnected Grainbelt project that was initiated in 2017.

The PestFacts WA team is excited to continue this collaboration and build upon this initiative in the future.

DPIRD’s disease modelling project is also working with Agworld and Back Paddock to deliver the suite of GRDC/DPIRD decision support tools on their platforms.  

For more information, or if you are interested in being involved in this collaboration, contact Senior research scientist Adam Sparks, Perth on +61 (0)8 9368 3689 or PestFacts WA newsletter editor Cindy Webster, Narrogin on +61 (0)8 9881 0201.



Article author: Cindy Webster (DPIRD Narrogin).

Article input: Jean Galloway (DPIRD Northam), Adam Sparks, (DPIRD Perth), Simon Foley (Agworld) and Chris Geeves (Back Paddock).