Knock Stem Weevils Over | GreenCast

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Knock Stem Weevils Over

Turf
26.08.2019
Argentine Stem Weevil from above

If you’ve ever faced Argentine Stem Weevils (ASW) in your greens, then you know how difficult these damaging pests can be to control. This is because over the summer, you may have multiple insect’s lifecycle stages – or even all of them – present at the same time. 

ASW go through multiple life stages before pupating and then becoming adults:

  • Adults – damage leaf tissue through windowing and panelling of leaves.
  • 1st and 2nd instar – the larvae hatch and feed inside the plant stem, disrupting the movement of water and minerals within the plant.
  • 3rd and 4th instar – the larvae cause damage by feeding on the plant’s crown and roots and do extensive damage.
  • Pupae – the ASW is dormant and develops in the soil from a larvae into and adult.

With overlapping lifecycles, where larvae often exist alongside adult ASW, populations can explode and become difficult to control with a curative program. Preventative Stem Weevil management is a must.

ASW Adult & Larvae

The key to ASW control: target both adults and larvae

The best control program targets both adult ASW and its larvae at the same time, requiring a combination of adulticide and larvicide treatments. One of the best ways to achieve this is by partnering two innovative products that complement each other by controlling across the life cycle: PROVAUNT Turf Insecticide and SPINNER Turf Insecticide.

PROVAUNT is a powerful new mode of action to the turf industry “INDOXAXARB” and is the only product labelled specifically for control of both adults and larvae, including the difficult to manage late-stage larvae. As a translaminar insecticide, it is easily absorbed into the waxy cuticles of plant tissue to deliver outstanding residual activity. Once lodged in the plant cell the active ingredient, powered by Meta Active Technology, is ingested or comes into contact with adults and larvae causing paralysis, which stops feeding followed by death.

SPINNER is a highly systemic dual mode of action insecticide containing CYANTRANILIPROLE + THIAMETHOXAM. It effectively treats early 1st and 2nd stage larvae in the turf, delivering an effective clean out followed by excellent longevity and prevention.

When partnered with each other, PROVAUNT and SPINNER offer complete protection by managing adults and all larvae stages, while also providing excellent management opportunities with overlapping life cycle stages.

PROVAUNT & SPINNER in the Life Cycle of the Argentine Stem Weevil. © Syngenta 2019.

Tips for getting the most out of PROVAUNT and SPINNER

Both PROVAUNT and SPINNER can be applied multiple times throughout spring and summer to both prevent and cure ASW infestation in your greens. Here are some tips on how to best incorporate both products in your management program:

  1. Use PROVAUNT and SPINNER to manage resistance. PROVAUNT’s new Mode of Action – Group 22A – makes it a great resistance management tool when used in rotation with SPINNER. Using PROVAUNT also allows you to reduce your usage of organophosphate technologies and synthetic pyrethroids when treating ASW, which according to anecdotal reports and US data referencing the closely related ABW, are resistant to synthetic pyrethroids. Considerations should be made to include a range of mode of actions to complement a full program and resistant management strategies.
     
  2. Don’t wash PROVAUNT in. Both PROVAUNT and SPINNER come in an easy-to-use Water Dispersible Granule (WG formulation) that dissolves when mixed with water. Local research has shown that the best results are achieved when PROVAUNT is not washed in.
     
  3. Apply early to avoid population build up. Yellowing leaves and wilted patches of turf are symptoms of ASW damage. Early monitoring and a preventative application strategy is essential. Once these signs appear, controls need to be applied immediately. PROVAUNT and SPINNER become central to your program managing both adult and larvae populations.
     
  4. A contact-knockdown is the most suitable for initial stage treatment post-winter. Target over-wintering adults when they first emerge in early spring/late winter with synthetic pyrethroids or chlorpyrifos. Research shows the first generation of the over-wintering Annual Bluegrass Weevil adult in the USA do not feed, however subsequent generations in summer can damage leaf tissue. It is likely that the closely related ASW behaves in a similar manner.

For more information on how PROVAUNT and SPINNER can help you achieve total ASW control, call 1800 022 035 or speak to your local Syngenta agent, Our Syngenta team are happy to assist in building ASW programs for your location.