Watchlist: Black keeled slug, Russian wheat aphid (RWA) and redlegged earth mite (RLEM)
Wednesday 27 May 2026 SARDIPestFacts
While some pests such as Russian wheat aphid (RWA) and redlegged earth mite (RLEM) are currently at low levels, recent rainfall and forecast cooler temperatures may trigger increased activity in coming weeks.
Ongoing monitoring of crops, volunteer hosts and weeds will be important to detect emerging risks and support timely management decisions.
Pest | Status | Current situation | Action |
|---|---|---|---|
Moderate | Recent rainfall events have triggered increased movement and feeding activity of black keeled slugs, particularly in paddocks with a history of slug damage. Slugs prefer cool, moist conditions and are commonly associated with heavy stubble retention and high soil moisture. Feeding damage typically occurs overnight on germinating seeds and emerging seedlings. Slugs shelter beneath stubble, clods and surface residues during the day. | Monitoring prior to sowing and during crop emergence is critical, particularly in high-risk paddocks. Use refuge traps and check paddocks following rain to assess activity and support timely baiting decisions. For better slug management refer to Slug control. | |
Low | Given the high level of pest activity observed following recent rain, it would not be surprising to see Russian wheat aphid activity develop in coming weeks. RWA can survive between seasons on volunteer cereals and grassy weeds. Early infestations are often patchy and difficult to detect, with symptoms including pale streaking and inward leaf rolling. Severe infestations later in the season may result in trapped heads. Moisture-stressed cereals may be more vulnerable to damage. | Monitor volunteer cereals, barley grass and newly emerging cereal crops, especially wheat and barley. Control the green bridge at least 2 to 3 weeks before sowing to reduce early colonisation risk. Refer to the Russian wheat aphid management guidelines for threshold-based management decisions. | |
Low | Conditions are becoming favourable for RLEM activity. Emerging mites are most active in cool, moist conditions and can rapidly build in canola, pulse and pasture paddocks, particularly where there is a history of RLEM or high weed burden. | Monitoring is especially important during crop emergence, as young seedlings are most vulnerable. Feeding damage appears as silvering or whitening of sprouts (cotyledons) and leaves. Severe infestations may reduce plant establishment. Refer to the Timerite and RLEM hatch timing tools to support monitoring and management decisions. |