What are Chafer Grubs?
Chafer grubs are the soil-dwelling larvae of chafer beetles. They are creamy coloured with an orange head and are about 1.5 cm in length, they have distinctive legs and will be found in the grass roots.
How can I control Chafer Grubs?
Nemasys Chafer Grub Killer is a chafer grub treatment containing Heterorhabditis bacteriophora a species of nematodes which controls infestations of chafer beetle larvae naturally, safely, and effectively.
Use Nemasys Chafer Grub Killer to deal with a chafer grub infestation, without any of the precautions associated with chemical use and the assurance that they are 100% safe for children, cats, dogs, other pets and wildlife.
Beneficial nematodes are living organisms, so they must be used before the expiry date (which is marked on the inside of the pack and will be around 2-3 weeks) and should be stored in the fridge until it is applied.
When can I apply Chafer Grub Killer Nematodes?
Generally as long as the grubs are near the surface and the soil temperature is above 12ºC (54ºF), nematodes can still be applied.
Autumn application - typically late August through to the end of October:
This is when the young grub larvae are active and most susceptible to the nematodes and the temperature is consistently above 12ºC (54ºF).
Spring application - typically early April to the end of May:
If you discover a severe infestation (or have had chafer grubs in the past) then we recommed that you treat your lawn with Nemasys® Chafer Grubs Killer in April/May. If you treat in April/May you should treat in September AS WELL.
How do Chafer Grub Killer Nematodes work?
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.
There are a number of Chafer Grub species with varying levels of resistance to Nematodes. The 'Garden Chafer' is the most commonly found chafer grub and is very susceptible to nematodes, but there are other minor species that are more resistant.
If after your initial treatment you continue to have an infestation it is highly likely you have a more resistant strain of chafer, such as the 'Welsh Chafer' or 'Summer Chafer'. It is advised to apply at double strength and more frequently in order to try to combat these grubs however this is still not guaranteed to combat the more resistant strains.
How do I apply Chafer Grub Killer nematodes?
Nemasys® chafer grub killer - hose end feeder instructions
Prior to applying the nematodes:
- Cut the grass short before treatment.
- Soil should be between 12°C and 30°C during application and for at least two weeks after.
- Irrigate the area to be treated prior to application in order to apply the nematodes to a moist lawn.
To avoid desiccation of the nematodes:
- Avoid direct sunlight; make applications in the evenings or in dull conditions
- Application during rain is highly desirable.
- It is very important to irrigate immediately after application, water the grass well so the nematodes are washed below the thatch layer into the soil to reach the roots where the larvae will be feeding.
- Ensure soil is moist for at least two weeks after application.
Nemasys® chafer grub application instructions using a Hose-end Feeder (500 sqm pack) :-
- Divide the 500 sqm to be treated into 100 sqm areas.
- Wash the feeder through with water to ensure it is clean.
- Divide the pack into 5 equal portions.
- Add 1 portion i.e. a fifth of the pack to feeder bowl. Then fill the bowl with water before attaching the hose.
- Taking care to keep the feeder in an upright position apply evenly to 100 sqm for 8 minutes using a side-to-side motion to keep the nematodes well mixed. During this time most of the nematodes will have been applied.
- Treat the same 100 sqm area again for a further 8 minutes to apply the remaining nematodes as well as to make sure they are adequately watered in.
- Repeat the procedure with the other 4 portions treating each 100 sqm area.
- Adhering strictly to the application timings will ensure that any remaining colour in the bowl will be due to inert carrier only and that you have performed an even application.
- Make sure the lawn does not dry out after applying nematodes and keep it well watered for at least two weeks. THIS IS VERY IMPORTANT!
This new method provides a simple and effective application, however, it is important to follow the instructions exactly to obtain even coverage.
Which pack size do I need?
To calculate your area measure the width and length of the area to be treated and multiple them by each other e.g. 50m x 10m = 500 sq.m
Can't see an answer to your question? Please contact us and we will be happy to assist you.