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Turf Maintenance Supplies

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Landscape, Horticulture and Sports
Turf Maintenance Supplies

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Landscape, Horticulture and Sports
Turf Maintenance Supplies

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Nemasys Chafer Grub Killer (500 m2)

Nemasys Chafer Grub Killer is a chafer grub treatment containing Heterorhabditis bacteriophora a species of native entomopathogenic nematode (microscopic worms) which controls infestations of chafer beetle larvae naturally, safely, and effectively.

The graphic below is designed to inform the user as to the life stage of the organism throughout the year.

There is one application window in the pests life cycle suitable for applying a chafer grub treatment.

The application window is during the late summer/autumn, from the middle of August to the middle of October.

For more in depth information, please read the Integrated Management Strategies For Maximising The Efficacy Of Entomopathogenic Nematodes document.


The mid August to mid October application window coincides with the larvae being at a young and susceptible life stage and the soil temperature being above 12ºC, which is the minimum point the nematodes are at their most active in the soil.

Once soil temperatures rise again in the following spring the larvae will have grown to a stage where effective control of any type is significantly reduced. This means that a pro-active preventative approach to controlling chafer larvae in turf areas is required. By undertaking a chafer grub treatment with Nemasys Chafer Grub Killer in the mid August to mid October application window, direct damage from the grubs and indirect damage from predators hunting for them in the following spring and summer is avoided.

Chafer Grub - Nematodes Life Cycle

Click to Enlarge

The nematodes work in the soil by seeking out the chafer beetle larvae and attack the pest by entering natural body openings. Once inside, they release bacteria (Photorhabdus spp.) that stops the pest from feeding, quickly killing the grub.

The nematodes then reproduce inside the dead grub and release a new generation of infective juvenile nematodes. These infective juveniles then disperse into the soil and search for further prey. If sustained this life cycle can lead to significantly reduced chafer grub populations in subsequent years.

Nemasys Chafer Grub Killer must be used within 3-4 weeks of being received, keep refrigerated until used.

Each pack of Nemasys Chafer Grub Killer treats up to 500m2.

We do not sell this product during the period when the larvae are not susceptible to control using nematodes.

To facilitate application at a volume of 2000 ltr/ha the following nozzle is recommended: Flat Fan Nozzle ISO Light Blue 10F110.




Chafer Grub Life Cycle


Chafer Grub Life Cycle Diagram
Further information on the control of leather jackets and chafer grubs with biological controls can be found within this article

How to Apply Nemasys Chafer Grub Killer



  • Nemasys Leatherjacket Killer should be applied using a handheld or hydraulic sprayer.
  • Take stock of nematodes 1-2 weeks prior to forecast application period to facilitate application in optimum circumstances.
  • Nematodes should be stored in a refrigerator at a temperature between 2-6 °C.
  • Apply when soil temperatures are warm (above 14 °C) and moist.
  • Apply 5-10 mm water to the turf the evening before treatment.
  • Subsequently apply 5 mm of water 1-2 hours before treatment.
  • Aerate the soil immediately prior to application with a sarel roller to ease nematode transition into soil contact.
  • Apply Entomopathogenic Nematodes 4-5 weeks post adult emergence.
  • Apply early in the morning, in the evening or on a cloudy day as the nematodes will be killed by UV light.
  • Apply when rain fall is forecast.
  • Remove all filters from the sprayer, these can be within the lance handle or top hat filters at the nozzle or alternatively in filter bowls within pipes after the pump.
  • Ensure that the sprayer is completely clean.
  • Apply with a penetrant wetting agent to enable more efficient passage into the soil.
  • It is important that the nematodes are delivered into contact with the soil as quickly as possible, excessive thatch within the turf sward will inhibit the nematodes passage into the soil.
  • Half fill the sprayer with clean water.
  • Put the contents of the pack into a bucket containing 5 litres of water (15-20 °C).
  • Stir well and allow to soak for 20-30 seconds.
  • Stir well once again and poor the entire solution into the spray tank.
  • Top up until the required amount of solution is in the tank.
  • Spray immediately after preparation over a wet surface. Maximum (12 bar pressure).
  • Use the whole pack in one go, as the distribution of nematodes in the pack is not homogenous.
  • Immediately after applying, water the grass area well (at least 2-5 litres per m²) so the nematodes are washed into the soil to reach the roots where the pests will be.
  • Ensure the turf area does not dry out after applying nematodes. If necessary, keep the area well-watered for at least two weeks.



This product is a biological control which is fully compatible with an Integrated Pest Management (IPM) programme.

  • This product is harmless to people, animals and the environment.

  • Biological controls are living organisms, as a result the exact timing of availability and application may differ according to local environmental conditions.

    This may cause a slight variance in the life cycle of the target pest species from year to year.

    Users are advised to closely monitor their local site for signs of pest appearance, susceptible life stages and crop damage.

  • Due to the fact that biological controls contain living organisms they have a short expiry date and should be refrigerated prior to use.

To aid the efficiency of the nematodes into the soil profile, apply with Premier Hydrate Wetting Agent.

For advice or further information regarding Nemasys Chafer Grub Killer, speak to a technical sales advisor on 01952 641949.