Home |
About nematodes |
Slugs |
Vine Weevils |
Chafer Grubs |
Leatherjackets |
Caterpillar and Codling Moth |
Ants |
Grow Your Own
Applying Your Nematodes | Buy products | News | How nematode products are made | Quality & care | Links | About us | Contact us
English Heritage is winning its battle against invading forces at Stonehenge, Wiltshire thanks to native nematodes.
Hosting 800,000 human visitors a year is one thing, but when the famous landmark found chafer grubs plaguing its grass
pathways, the world-renowned visitor attraction needed help! It came in the form of Nemasys Chafer Grub Killer, produced
by Becker Underwood, the world's largest producer of nematodes, which was applied to 5000 sq m of grass to the south-east
of the stones.
Chafer grubs, one of the top ten garden pests according to the RHS, had caused problems for years by eating the grass
roots. This was exacerbated by jackdaws pulling up the grass to seek out the grubs, resulting in unsightly bald patches.
Add to that the constant flow of visitors and English Heritage had to keep moving visitor paths away from the damage that
encircled the famous stones. There was yet another problem too - when the chafer grubs hatched, the resulting swarm of
beetles would fly up at the visitors who found it extremely off putting to say the least.
Due to the large number of visitors including children and with local wildlife and sheep grazing in the neighbouring
fields, there was no way that English Heritage wanted to resort to chemicals so they had to come up with a natural
environmentally friendly solution - Nemasys Chafer Grub Killer. Within a week of the first application, back in September
2006, the secondary damage from wildlife reduced considerably. A review of the result in April 2007 has led English
Heritage to order more Nemasys Chafer Grub Killer - enough to treat an area twice the size of the original application.
Says English Heritage's Chris Bally, Landscape manager for Stonehenge and the south-west, "Nemasys Chafer Grub Killer has
cured the treated areas. We found it extremely effective and chafer grubs have not caused us a problem at all this year
on the treated areas. Now we are targeting other infected areas and hopefully we will not have a chafer grub problem at
all in a couple of years."
[top]
A vintage year?
2005 was a good year for crane flies! Whilst these insects should be left alone in the wild, lawn proud gardeners do not
necessarily want them in their ‘own back yard’. If your lawn is home to the leatherjacket grubs, (the grub stage of the
Daddy-Longlegs) then you are probably inviting unwanted wildlife guests in for dinner. For wildlife will visit your lawn,
dig it up and leave a mess in their search for food.
To combat leatherjackets use Nemasys Leather Jacket Killer, the nematode control. Nematodes are microscopic worms that
occur naturally in the soil but in insufficient numbers. Water Nemasys into your lawn during late August through to the
end of October when the leatherjackets are active. You will know when to apply because towards the end of August you will
see the adult crane flies and then a few days later they will lay their eggs. As the eggs hatch quickly, aim to apply two
weeks after you see the adults.
Chafer grubs do similar damage inviting similar predators. Chafer beetles emerge from the lawn in May/June and lay their
eggs in the ground in two weeks. The eggs hatch into grubs feeding on the grass roots in August and September before
burrowing deep into the ground. If you have an infestation, log it on the national site
www.chafersurvey.co.uk, where you will also find
details of how to combat this pest.
[top]
And what’s more it is safe for bees...
The honeybee is only now found in beekeepers’ hives as there are no wild honeybees left in this country.
Bees have an extremely important role to play in food production and with native species constantly under threat from
parasites and other predators, gardeners are keen not to harm the bees that visit their plots. So if this is the case
why would gardeners want to use pesticides, and especially imidaclorprid, to make life even harder for the bee?
One of the statements on a chemical product recently introduced for the control chaffer grubs in lawns containing the
active ingredient imidaclorprid says...
If you use chemical pest controls you have to follow strict safety precautions indicated on the pack, especially in
regard to children, pets and wildlife.
For example chemical controls for chafer grubs and leatherjackets have implications for grazing animals, which should be
excluded from the ground for four weeks after application. This can mean finding other grassed areas for your rabbit or
horse to graze. Nematodes have been especially useful in controlling chafer grubs at a Norfolk stud because, whilst
killing chafer grubs, Nemasys does not affect the horses. So with nematodes you do not have a safety issue.
In fact they are so safe that the pack says to store it in the fridge - to keep the nematodes fresh until they are used
before the expiry date.
[top]
Straight from the horse's mouth
A prestigious stud farm in Thetford, Norfolk has found a winning formula in its annual battle with chafer grubs, which
have plagued its land for years. Head gardener of the Shadwell Estates Company Limited’s 6,000 acre estate, Stan Copeman,
has won control over the grubs after trials of Becker Underwood’s nematode based Chafer Grub Killer, available to both
commercial and home users, on two hectares of grounds comprising the ornamental lawns and playing field.
“Our grounds used to be like a ploughed field each year as the birds dug up the grass to get to the grubs. This year,
where we applied Nemasys Chafer Grub Killer, we saw a dramatic difference,” says Stan. “The birds stopped feeding within
10 days on the treated areas, so it was clear that the nematodes had done the job.”
Shadwell Estates stud farm, which plays host to over 200 horses each spring, has a light sandy soil, perfect for the
chafer grubs to move through, eating the roots of the grass as they go. Birds then come along and rip up the grass to get
at the grubs, causing devastating damage as they harvest an easy meal.
Stan Copeman had tried other remedies, without success, so when he read about Becker Underwood’s nematode solution in a
trade magazine, he called them for more information and advice.
As a result of that advice, the nematodes were applied using an Ecosprayer fitted with flood jets but no filters, mounted
on a compact tractor. First the ground was watered and then the nematodes applied, including a wetting agent to ensure
good application. The ground was then kept moist so that the nematodes were washed through into the soil to get at the
grubs.
“We found the whole process very simple and the results are great,” says Stan. “We will certainly be using Nemasys Chafer
Grub Killer again this year as infestation from surrounding areas will have taken place.”
[top]
Chafer Grubs and Leather jackets are grass root problems for Norfolk gardeners
Parts of Norfolk, including Taverham are currently seeing an invasion of chafer grubs attacking garden lawns, golf
courses, amenity areas, aerodromes and even graveyards, where the pests are breeding and birds and animals are causing
problems as they dig up the turf looking for the tasty grubs. The news comes from Becker Underwood’s advice line, which
has received more calls from the Norfolk area this season than any other. The company produces the Nemasys range of pest
controls and their chafer grub and leatherjacket killers are the only answer for homeowners facing the same problem.
Says Dr. Graeme Gowling, head of Becker Underwood’s nematode division, “We have been amazed by the number of calls we
have received from the Norfolk area where people have problems with chafer grubs at the moment. The reason for this is
because the soil is sandy. Now is the time to combat chafer grubs. Leatherjackets, which emerge into crane flies, love
the same conditions and can soon follow. Then it will be time to treat lawns to stop the next generation from eating your
grass roots.”
From August to October chafer grubs and leatherjackets can wreak havoc on well cared for turf and lawns, bringing misery to
proud gardeners across the land. Now these two pests can be dealt with effectively using Becker Underwood’s new Nemasys
range, which includes Nemasys Chafer Grub Killer and Nemasys Leather Jacket Killer.
By using Nemasys, which is safe for children pets and wildlife, the gardener adds more nematodes to the soil so that
there are enough of them to attack the target pest. The nematodes used are naturally occurring organisms that are already
present in the soil, number of nematodes falls back to the background level of the environment, their food source having
been eliminated.
Chafer beetles emerge from the lawn in May/June. They lay their eggs, which hatch into grubs (which are creamy coloured
and up to 1.5 cm (0.6 inch) in length, have legs and a distinctive reddish brown head) that feed on the grass roots. They
then lie dormant deep in the soil before moving to the surface in the spring to emerge as beetles again. There is no
chemical control for chafer grubs and if the chafer's life cycle is not broken re-infestation occurs and the problem gets
progressively worse.
The nematodes (Heterorhabditis megidis) seek out the chafer grubs and attack the pest by entering natural body openings.
Once inside, they release bacteria that stops the pest from feeding, quickly killing the pest. They do not stop there. The
nematodes reproduce inside the dead pest and release a new generation of hungry infective nematodes, which disperse and
search for further prey Treat affected areas with Nemasys Chafer Grub Killer in August/September, which is when the grubs
are active.
Leatherjackets are the larval stage of the crane fly or daddy-long-legs. Leatherjacket larvae are about 2.5cm (1" long),
greyish black in colour, legless and with no distinct head.
In summer leatherjackets pupate. In August they start to lay eggs re-infesting lawns. Within two weeks eggs hatch. The
young start to feed, continuing throughout winter, ready to gorge on grass roots in spring. Grass growth slows and yellow
patches appear. Grass is easily pulled up, with little or no root growth.
In August gardeners may see clouds of daddy-long-legs emerging from lawns in the early morning and this, as well as the
listed damage, is a sure sign of leatherjacket infestation. Starlings peck at the grass in an attempt to eat the grubs
and wildlife, such as foxes and badgers, can also create a lot of damage as they dig up your lawn in search of grubs for
food.
Apply Nemasys Leather Jacket Killer (which contains the nematode Steinernema feltiae) when the young leatherjackets are
active in the soil, this is typically late August through to the end of October. When you start to see the adult
daddy-long-legs in your garden (towards the end of August) you will know that in a few days they will be laying eggs.
These will hatch quickly, therefore, aim to apply about a week to two weeks after you see the adults.
Apply Nemasys to moist lawns and then water the nematodes in well so that they are washed through the grass and into the
soil to reach the roots where the chafer grubs or leatherjackets will be. Keep the lawn well watered for at least two
weeks after to make sure the lawn does not dry out.
All nematode products are found naturally in the soils of the country within which they are sold. Using nematode products
artificially boosts the number of nematodes in an area where there is a large number of pests. This helps to reduce the
number of pests insects in that area.
[top]
No Chafer Grub and Leather jackets on our golf course
Dustin Houghton, the course manager/Head Greenkeeper at Seaford Head Golf Course, East Sussex is a happy man after Becker
Underwood’s nematodes stopped his greens and fairways from being wrecked by hundreds of crows that frequent the course
looking for tasty chafer grubs and leather jackets.
From August to October chafer grubs and leatherjackets can wreak havoc on well cared for turf and lawns, bringing misery
to proud gardeners across the land. Now, as confirmed by Dustin, these two pests can be dealt with effectively using
Becker Underwood’s new Nemasys range, which includes Nemasys Chafer Grub Killer and Nemasys Leather Jacket Killer.
“I was despairing,” says Dustin. “As Seaford is a local authority course we take the use of chemicals seriously and
because of the EMAS policy we have not been able to use Chlorpyrifos and Gamma HCH to control the pests for over five
years. The crows attacked the course in abundance looking for chafer grubs and leather jackets and we tried everything
from making loud noises to feeding them with corn. I got in touch with various organisations and then a supplier put me
in touch with Becker Underwood who was trialling products for the pests.
“We have been trialling the products for two years now and we have certainly seen a tremendous difference,” continues
Dustin. “We have treated eight trial sites on the fairways and treated all the greens and we seem to be pest free.”
“We used to spend around £4,500/£5,000 to repair and replace turf where the areas have been wrecked by feeding birds,”
says Dustin “This outlay has been reduced by half. We are a text book case for chafer grubs and Leatherjackets – well
drained Downland site and the grubs prefer the top slopes so I am glad that Becker Underwood came up with a solution!”
By using Nemasys, which is safe for children pets and wildlife, the gardener adds more nematodes to the soil so that
there are enough of them to attack the target pest. The nematodes used are naturally occurring organisms that are already
present in the soil, but their numbers are insufficient to deal with an infestation. After a period of time the number of
nematodes falls back to the background level of the environment, their food source having been eliminated.
Chafer beetles emerge from the lawn in May/June. They lay their eggs, which hatch into grubs (which are creamy coloured
and up to 1.5 cm (0.6 inch) in length, have legs and a distinctive reddish brown head) that feed on the grass roots. They
then lie dormant deep in the soil before moving to the surface in the spring to emerge as beetles again. There is no
chemical control for chafer grubs and if the chafer's life cycle is not broken re-infestation occurs and the problem gets
progressively worse.
The nematodes (Heterorhabditis megidis) seek out the chafer grubs and attack the pest by entering natural body openings.
Once inside, they release bacteria that stops the pest from feeding, quickly killing the pest. They do not stop there. The
nematodes reproduce inside the dead pest and release a new generation of hungry infective nematodes, which disperse and
search for further prey Treat affected areas with Nemasys Chafer Grub Killer in August/September, which is when the grubs
are active.
Leatherjackets are the larval stage of the crane fly or daddy-long-legs. Leatherjacket larvae are about 2.5cm (1" long),
greyish black in colour, legless and with no distinct head.
In summer leatherjackets pupate. In August they start to lay eggs re-infesting lawns. Within two weeks eggs hatch. The
young start to feed, continuing throughout winter, ready to gorge on grass roots in spring. Grass growth slows and yellow
patches appear. Grass is easily pulled up, with little or no root growth.
In August gardeners may see clouds of daddy-long-legs emerging from lawns in the early morning and this, as well as the
listed damage, is a sure sign of leatherjacket infestation. Starlings peck at the grass in an attempt to eat the grubs and
wildlife, such as foxes and badgers, can also create a lot of damage as they dig up your lawn in search of grubs for food.
Apply Nemasys Leather Jacket Killer (which contains the nematode Steinernema feltiae) when the young leatherjackets are
active in the soil, this is typically late August through to the end of October. When you start to see the adult
daddy-long-legs in your garden (towards the end of August) you will know that in a few days they will be laying eggs.
These will hatch quickly, therefore, aim to apply about a week to two weeks after you see the adults.
Apply Nemasys to moist lawns and then water the nematodes in well so that they are washed through the grass and into the
soil to reach the roots where the chafer grubs or leatherjackets will be. Keep the lawn well watered for at least two
weeks after to make sure the lawn does not dry out.
All nematode products are found naturally in the soils of the country within which they are sold. Using nematode products
artificially boosts the number of nematodes in an area where there is a large number of pests. This helps to reduce the
number of pests insects in that area.
Nemasys Chafer Grub Killer and Nemasys Leather Jacket Killer come in different pack sizes to meet the varying needs of
gardeners:
[top]
Turf wars go biological
A new solution for the control of chafer grubs by Simon Piggott, Development Scientist, Becker Underwood, Littlehampton, UK.
Chafer grubs are the larval stages of the May / June beetle and are an increasing problem in turf throughout Europe. They
can create devastating damage to turf, either directly by the grubs feeding on roots or, indirectly by predators feeding
on the grubs. When grubs feed on roots they create characteristic yellowing of the turf and in severe cases damaged turf
can easily be rolled back since much of the root system has been severed (see plate 1).
High infestations of grubs in the soil provide a very attractive food source for predators such as badgers, foxes and
crows. These predators can focus on infested areas, tearing away turf to expose grubs and can completely remove patches
of turf over a wide area. In the UK there are a number of different species of chafer, however the most common is the
Garden Chafer (Phyllopertha horticola).
Pest Biology
The Garden chafer follows an annual life cycle. Adults emerge in May/June and have a metallic green head/thorax and reddish-brown hairy wing cases. Once emerged they immediately mate and the females burrow in the ground to lay eggs and it has been reported that females will lay eggs up to a 4 km radius from her emergence site. However, there seems to be a tendency for chafer grubs to re-infest the same area annually. After 3 to 5 weeks later the eggs hatch into small larvae which have legs and are characteristically ‘C’ shaped with a white body and a reddish brown head. The grubs move up to the soil / turf interface and stay close to the soil surface until mid-October when they move deeper in the soil during the winter. The grubs remain inactive until the following April when they pupate (Figure 2). Methods of Control
Chemical controls have been effective and economically attractive but recent moves to restrict the use of chemicals and also the preference to look for alternatives have led to the hunt for a biological alternative. Parasitic nematodes have been used for the control of other pests for many years and there are nematodes that are very good for controlling grubs in horticulture and for the home and garden sector. However, it has taken much research to develop a method for controlling chafer grubs in amenity turf where factors such as thatch and turf management need to be taken into account. Research over the past 3 years in the UK and The Netherlands has led to the development of Nemasys G based on the nematode Heterorhabditis sp. a species that has evolved to target pests such as grub larvae and that provides the perfect biological solution to the problem of Garden Chafer grubs. How do nematodes work?
These nematodes are natural predators of the pest and will only target insects, actively seeking out grubs in the soil and entering them through natural body openings. Once inside they release symbiotic bacteria, quickly killing the grub within 2 to 3 days. The nematodes reproduce inside the dead grub and release a new generation of infective juveniles which disperse in search of further prey. All nematode products are found naturally in the soils of the country within which they are sold and using nematodes, artificially boosts the numbers of nematodes in an area where there has been a large number of pests. This helps to reduce the number of pest insects in that area and after a period of time the number of nematodes falls back down to a background level. Since these nematodes are specific to insect pests, they are completely harmless to other organisms including plants (turf), wildlife, operators and course users. Development of a biological solution
Sites were found both in the UK and in The Netherlands to try out 3 different types of nematode to see which was better for garden chafer control. It was found that one nematode in particular gave consistent results when applied with enough water to allow it to penetrate through the thatch and down to the site where the grubs were living. Field Studies
In the UK, sites were found for testing of nematodes against the garden chafer, one at the Greater Manchester Police Force Training College and the other on the south coast at Seaford Head Golf Course. In total there were 5 trials sites in the UK and the results indicate that the Heterorhabditis megidis nematode was a very effective control measure for the grubs. Other nematodes were also tried but these failed to give sufficient control. The trial was replicated a further time in The Netherlands and this was undertaken on at Toxandria, a golf course near Breda. The best result, at Seaford, was achieved due to the application of the nematodes with rainfall although the results at the other sites were also applied to moist soils. Overall, the Heterorhabditis megidis nematode achieved a control that was consistent. Use of the nematodes reduced the level of grubs in the turf and in particular, Seaford Head site showed a significant reduction in the level of damage caused by the secondary predation which was normally noticed by staff and turf users. Targeting is the issue
Previous use of nematodes has shown that the application must be done to moist soil and if the soil moisture is maintained for approximately 2 weeks after application the control of the grubs pest will be greatly improved. One of the interesting features of the work highlighted the importance of the movement of nematodes through the thatch layer. It is known that the grubs are closest to the surface of the soil during the autumn (typically during August and September – see Figure 2) but there is often quite a thick layer of thatch that impedes the movement of the nematodes down to the soil level where the grubs are feeding on the roots. Therefore, nematodes are best washed through the thatch with plenty of water and use of a wetting agent aids in penetration (similar to the use of wetting agents to prevent dry patches). Summary
The use of nematodes for the control of chafer grubs has been proven with a UK isolated nematode and at a level that is consistent and provides reduction in secondary damage to turf. Important features of the use of nematodes include sufficient water to allow the nematode to move through the turf and thatch and also at the correct time of year to allow targeting of the grubs where the grubs reside. Providing adequate water and timing, chafer grub populations can be reduced and the food source for predatory animals diminished. Nemasys G is manufactured by Becker Underwood (Telephone; 01903 732323, www.beckerunderwood.com and is available through Avoncrop Amenity (tel;01344 426600) and Aitken’s Sportsturf (tel; 01977 681155) from the beginning of August 2003.
Plate 1. Damage caused to turf by the garden chafer grub.
Figure 1. Summary of 7 trials undertaken on three sites since 2001.
Figure 2. Movement of grubs in the soil during the year and when nematodes are best placed. [top] National Chafer Survey If your lawn is looking yellow or has birds and/or wildlife scratching it up you could hold part of the key to where one of Britain’s major lawn pests is active. A new website has been launched to track where chafer grubs are causing misery to proud lawn owners throughout the country. www.chafersurvey.co.uk, which was launched this week, shows how to recognise chafer grub damage, what the pest looks like and how to combat it. Homeowners can register their chafer outbreak quickly and easily without their information being used for individual marketing purposes. Chafer grubs were the number five pest in the RHS top pest enquiries in 2004 (source: www.rhs.org.uk/news/chafersurvey.asp). They can be found in specific areas throughout the country and the website is designed to collect partial postcode information so that the chafer hotspots can be identified. As leatherjackets can do similar damage, the site also gives information to identify that pest, so that there is no confusion. The site’s promoters, Becker Underwood, produce the Nemasys range of nematode pest controls and European general manager, Dr Graeme Gowling, explains, “Chafer grubs cause misery to proud lawn owners up and down the country, but as far as we know, no-one has a map showing where the pest is causing problems. With the public’s support, we can identify those areas and homeowners can find out how to rid themselves of the problem.” Chafer grubs are creamy coloured and about 1.5 cm (0.6 inch) in length, have distinctive legs and are found in the root systems of plants and lawns. They are often mistaken for vine weevil larvae but chafer grubs have legs, whereas vine weevil larvae do not. Chafer beetles emerge from the lawn in May/June and lay their eggs in the ground in two weeks. The eggs hatch into grubs feeding on the grass roots in August and September before burrowing deep into the ground. They then lie dormant deep in the soil before moving to the surface in the spring to emerge as beetles again. So log on to www.chafersurvey.co.uk to find out more about chafer grubs and to log any sightings. The website promoters emphasise that the data collection will in no way link back to the individual so there should be no concern about being targeted for direct marketing purposes. [top]
Applying Your Nematodes | Buy products | News | How nematode products are made | Quality & care | Links | About us | Contact us
News archives - Nemasys Chafer Grub Killer & Nemasys Leatherjacket Killer
- Press Information
- Stonehenge siege lifted
- A vintage year?
- And what’s more it is safe for bees...
- Safety with Nematodes
- Straight from the horse's mouth
- Chafer Grubs and Leather jackets are grass root problems for Norfolk gardeners
- No Chafer Grub and Leather jackets on our golf course
- Turf wars go biological
- National Chafer Survey
English Heritage is winning its battle against invading forces at Stonehenge, Wiltshire thanks to native nematodes.
Hosting 800,000 human visitors a year is one thing, but when the famous landmark found chafer grubs plaguing its grass
pathways, the world-renowned visitor attraction needed help! It came in the form of Nemasys Chafer Grub Killer, produced
by Becker Underwood, the world's largest producer of nematodes, which was applied to 5000 sq m of grass to the south-east
of the stones.
Chafer grubs, one of the top ten garden pests according to the RHS, had caused problems for years by eating the grass
roots. This was exacerbated by jackdaws pulling up the grass to seek out the grubs, resulting in unsightly bald patches.
Add to that the constant flow of visitors and English Heritage had to keep moving visitor paths away from the damage that
encircled the famous stones. There was yet another problem too - when the chafer grubs hatched, the resulting swarm of
beetles would fly up at the visitors who found it extremely off putting to say the least.
Due to the large number of visitors including children and with local wildlife and sheep grazing in the neighbouring
fields, there was no way that English Heritage wanted to resort to chemicals so they had to come up with a natural
environmentally friendly solution - Nemasys Chafer Grub Killer. Within a week of the first application, back in September
2006, the secondary damage from wildlife reduced considerably. A review of the result in April 2007 has led English
Heritage to order more Nemasys Chafer Grub Killer - enough to treat an area twice the size of the original application.
Says English Heritage's Chris Bally, Landscape manager for Stonehenge and the south-west, "Nemasys Chafer Grub Killer has
cured the treated areas. We found it extremely effective and chafer grubs have not caused us a problem at all this year
on the treated areas. Now we are targeting other infected areas and hopefully we will not have a chafer grub problem at
all in a couple of years."
[top]
A vintage year?
2005 was a good year for crane flies! Whilst these insects should be left alone in the wild, lawn proud gardeners do not
necessarily want them in their ‘own back yard’. If your lawn is home to the leatherjacket grubs, (the grub stage of the
Daddy-Longlegs) then you are probably inviting unwanted wildlife guests in for dinner. For wildlife will visit your lawn,
dig it up and leave a mess in their search for food.
To combat leatherjackets use Nemasys Leather Jacket Killer, the nematode control. Nematodes are microscopic worms that
occur naturally in the soil but in insufficient numbers. Water Nemasys into your lawn during late August through to the
end of October when the leatherjackets are active. You will know when to apply because towards the end of August you will
see the adult crane flies and then a few days later they will lay their eggs. As the eggs hatch quickly, aim to apply two
weeks after you see the adults.
Chafer grubs do similar damage inviting similar predators. Chafer beetles emerge from the lawn in May/June and lay their
eggs in the ground in two weeks. The eggs hatch into grubs feeding on the grass roots in August and September before
burrowing deep into the ground. If you have an infestation, log it on the national site
www.chafersurvey.co.uk, where you will also find
details of how to combat this pest.
[top]
And what’s more it is safe for bees...
The honeybee is only now found in beekeepers’ hives as there are no wild honeybees left in this country.
Bees have an extremely important role to play in food production and with native species constantly under threat from
parasites and other predators, gardeners are keen not to harm the bees that visit their plots. So if this is the case
why would gardeners want to use pesticides, and especially imidaclorprid, to make life even harder for the bee?
One of the statements on a chemical product recently introduced for the control chaffer grubs in lawns containing the
active ingredient imidaclorprid says...
- High risk to bees.
- Apply away from bees.
- Do not apply when flowering weeds are present.
If you use chemical pest controls you have to follow strict safety precautions indicated on the pack, especially in
regard to children, pets and wildlife.
For example chemical controls for chafer grubs and leatherjackets have implications for grazing animals, which should be
excluded from the ground for four weeks after application. This can mean finding other grassed areas for your rabbit or
horse to graze. Nematodes have been especially useful in controlling chafer grubs at a Norfolk stud because, whilst
killing chafer grubs, Nemasys does not affect the horses. So with nematodes you do not have a safety issue.
In fact they are so safe that the pack says to store it in the fridge - to keep the nematodes fresh until they are used
before the expiry date.
[top]
Straight from the horse's mouth
A prestigious stud farm in Thetford, Norfolk has found a winning formula in its annual battle with chafer grubs, which
have plagued its land for years. Head gardener of the Shadwell Estates Company Limited’s 6,000 acre estate, Stan Copeman,
has won control over the grubs after trials of Becker Underwood’s nematode based Chafer Grub Killer, available to both
commercial and home users, on two hectares of grounds comprising the ornamental lawns and playing field.
“Our grounds used to be like a ploughed field each year as the birds dug up the grass to get to the grubs. This year,
where we applied Nemasys Chafer Grub Killer, we saw a dramatic difference,” says Stan. “The birds stopped feeding within
10 days on the treated areas, so it was clear that the nematodes had done the job.”
Shadwell Estates stud farm, which plays host to over 200 horses each spring, has a light sandy soil, perfect for the
chafer grubs to move through, eating the roots of the grass as they go. Birds then come along and rip up the grass to get
at the grubs, causing devastating damage as they harvest an easy meal.
Stan Copeman had tried other remedies, without success, so when he read about Becker Underwood’s nematode solution in a
trade magazine, he called them for more information and advice.
As a result of that advice, the nematodes were applied using an Ecosprayer fitted with flood jets but no filters, mounted
on a compact tractor. First the ground was watered and then the nematodes applied, including a wetting agent to ensure
good application. The ground was then kept moist so that the nematodes were washed through into the soil to get at the
grubs.
“We found the whole process very simple and the results are great,” says Stan. “We will certainly be using Nemasys Chafer
Grub Killer again this year as infestation from surrounding areas will have taken place.”
[top]
Chafer Grubs and Leather jackets are grass root problems for Norfolk gardeners
Parts of Norfolk, including Taverham are currently seeing an invasion of chafer grubs attacking garden lawns, golf
courses, amenity areas, aerodromes and even graveyards, where the pests are breeding and birds and animals are causing
problems as they dig up the turf looking for the tasty grubs. The news comes from Becker Underwood’s advice line, which
has received more calls from the Norfolk area this season than any other. The company produces the Nemasys range of pest
controls and their chafer grub and leatherjacket killers are the only answer for homeowners facing the same problem.
Says Dr. Graeme Gowling, head of Becker Underwood’s nematode division, “We have been amazed by the number of calls we
have received from the Norfolk area where people have problems with chafer grubs at the moment. The reason for this is
because the soil is sandy. Now is the time to combat chafer grubs. Leatherjackets, which emerge into crane flies, love
the same conditions and can soon follow. Then it will be time to treat lawns to stop the next generation from eating your
grass roots.”
From August to October chafer grubs and leatherjackets can wreak havoc on well cared for turf and lawns, bringing misery to
proud gardeners across the land. Now these two pests can be dealt with effectively using Becker Underwood’s new Nemasys
range, which includes Nemasys Chafer Grub Killer and Nemasys Leather Jacket Killer.
By using Nemasys, which is safe for children pets and wildlife, the gardener adds more nematodes to the soil so that
there are enough of them to attack the target pest. The nematodes used are naturally occurring organisms that are already
present in the soil, number of nematodes falls back to the background level of the environment, their food source having
been eliminated.
Chafer beetles emerge from the lawn in May/June. They lay their eggs, which hatch into grubs (which are creamy coloured
and up to 1.5 cm (0.6 inch) in length, have legs and a distinctive reddish brown head) that feed on the grass roots. They
then lie dormant deep in the soil before moving to the surface in the spring to emerge as beetles again. There is no
chemical control for chafer grubs and if the chafer's life cycle is not broken re-infestation occurs and the problem gets
progressively worse.
The nematodes (Heterorhabditis megidis) seek out the chafer grubs and attack the pest by entering natural body openings.
Once inside, they release bacteria that stops the pest from feeding, quickly killing the pest. They do not stop there. The
nematodes reproduce inside the dead pest and release a new generation of hungry infective nematodes, which disperse and
search for further prey Treat affected areas with Nemasys Chafer Grub Killer in August/September, which is when the grubs
are active.
Leatherjackets are the larval stage of the crane fly or daddy-long-legs. Leatherjacket larvae are about 2.5cm (1" long),
greyish black in colour, legless and with no distinct head.
In summer leatherjackets pupate. In August they start to lay eggs re-infesting lawns. Within two weeks eggs hatch. The
young start to feed, continuing throughout winter, ready to gorge on grass roots in spring. Grass growth slows and yellow
patches appear. Grass is easily pulled up, with little or no root growth.
In August gardeners may see clouds of daddy-long-legs emerging from lawns in the early morning and this, as well as the
listed damage, is a sure sign of leatherjacket infestation. Starlings peck at the grass in an attempt to eat the grubs
and wildlife, such as foxes and badgers, can also create a lot of damage as they dig up your lawn in search of grubs for
food.
Apply Nemasys Leather Jacket Killer (which contains the nematode Steinernema feltiae) when the young leatherjackets are
active in the soil, this is typically late August through to the end of October. When you start to see the adult
daddy-long-legs in your garden (towards the end of August) you will know that in a few days they will be laying eggs.
These will hatch quickly, therefore, aim to apply about a week to two weeks after you see the adults.
Apply Nemasys to moist lawns and then water the nematodes in well so that they are washed through the grass and into the
soil to reach the roots where the chafer grubs or leatherjackets will be. Keep the lawn well watered for at least two
weeks after to make sure the lawn does not dry out.
All nematode products are found naturally in the soils of the country within which they are sold. Using nematode products
artificially boosts the number of nematodes in an area where there is a large number of pests. This helps to reduce the
number of pests insects in that area.
[top]
No Chafer Grub and Leather jackets on our golf course
Dustin Houghton, the course manager/Head Greenkeeper at Seaford Head Golf Course, East Sussex is a happy man after Becker
Underwood’s nematodes stopped his greens and fairways from being wrecked by hundreds of crows that frequent the course
looking for tasty chafer grubs and leather jackets.
From August to October chafer grubs and leatherjackets can wreak havoc on well cared for turf and lawns, bringing misery
to proud gardeners across the land. Now, as confirmed by Dustin, these two pests can be dealt with effectively using
Becker Underwood’s new Nemasys range, which includes Nemasys Chafer Grub Killer and Nemasys Leather Jacket Killer.
“I was despairing,” says Dustin. “As Seaford is a local authority course we take the use of chemicals seriously and
because of the EMAS policy we have not been able to use Chlorpyrifos and Gamma HCH to control the pests for over five
years. The crows attacked the course in abundance looking for chafer grubs and leather jackets and we tried everything
from making loud noises to feeding them with corn. I got in touch with various organisations and then a supplier put me
in touch with Becker Underwood who was trialling products for the pests.
“We have been trialling the products for two years now and we have certainly seen a tremendous difference,” continues
Dustin. “We have treated eight trial sites on the fairways and treated all the greens and we seem to be pest free.”
“We used to spend around £4,500/£5,000 to repair and replace turf where the areas have been wrecked by feeding birds,”
says Dustin “This outlay has been reduced by half. We are a text book case for chafer grubs and Leatherjackets – well
drained Downland site and the grubs prefer the top slopes so I am glad that Becker Underwood came up with a solution!”
By using Nemasys, which is safe for children pets and wildlife, the gardener adds more nematodes to the soil so that
there are enough of them to attack the target pest. The nematodes used are naturally occurring organisms that are already
present in the soil, but their numbers are insufficient to deal with an infestation. After a period of time the number of
nematodes falls back to the background level of the environment, their food source having been eliminated.
Chafer beetles emerge from the lawn in May/June. They lay their eggs, which hatch into grubs (which are creamy coloured
and up to 1.5 cm (0.6 inch) in length, have legs and a distinctive reddish brown head) that feed on the grass roots. They
then lie dormant deep in the soil before moving to the surface in the spring to emerge as beetles again. There is no
chemical control for chafer grubs and if the chafer's life cycle is not broken re-infestation occurs and the problem gets
progressively worse.
The nematodes (Heterorhabditis megidis) seek out the chafer grubs and attack the pest by entering natural body openings.
Once inside, they release bacteria that stops the pest from feeding, quickly killing the pest. They do not stop there. The
nematodes reproduce inside the dead pest and release a new generation of hungry infective nematodes, which disperse and
search for further prey Treat affected areas with Nemasys Chafer Grub Killer in August/September, which is when the grubs
are active.
Leatherjackets are the larval stage of the crane fly or daddy-long-legs. Leatherjacket larvae are about 2.5cm (1" long),
greyish black in colour, legless and with no distinct head.
In summer leatherjackets pupate. In August they start to lay eggs re-infesting lawns. Within two weeks eggs hatch. The
young start to feed, continuing throughout winter, ready to gorge on grass roots in spring. Grass growth slows and yellow
patches appear. Grass is easily pulled up, with little or no root growth.
In August gardeners may see clouds of daddy-long-legs emerging from lawns in the early morning and this, as well as the
listed damage, is a sure sign of leatherjacket infestation. Starlings peck at the grass in an attempt to eat the grubs and
wildlife, such as foxes and badgers, can also create a lot of damage as they dig up your lawn in search of grubs for food.
Apply Nemasys Leather Jacket Killer (which contains the nematode Steinernema feltiae) when the young leatherjackets are
active in the soil, this is typically late August through to the end of October. When you start to see the adult
daddy-long-legs in your garden (towards the end of August) you will know that in a few days they will be laying eggs.
These will hatch quickly, therefore, aim to apply about a week to two weeks after you see the adults.
Apply Nemasys to moist lawns and then water the nematodes in well so that they are washed through the grass and into the
soil to reach the roots where the chafer grubs or leatherjackets will be. Keep the lawn well watered for at least two
weeks after to make sure the lawn does not dry out.
All nematode products are found naturally in the soils of the country within which they are sold. Using nematode products
artificially boosts the number of nematodes in an area where there is a large number of pests. This helps to reduce the
number of pests insects in that area.
Nemasys Chafer Grub Killer and Nemasys Leather Jacket Killer come in different pack sizes to meet the varying needs of
gardeners:
| Product | Size | RRP (incl. of VAT) |
| Nemasys Leatherjacket Killer | 100m2 | £19.95 |
| Nemasys Chafer Grub Killer | 100m2 | £32.95 |
| Nemasys Chafer Grub Killer | 20m2 | £14.95 |
Other Nemasys products: |
||
| Nemaslug Slug Killer | 40m2 | £11.95 |
| Nemaslug Slug Killer | 100m2 | £24.95 |
| Nemasys Vine weevil Killer | 12m2 | £9.95 |
| Nemasys Vine Weevil Killer | 100m2 | £32.95 |
A new solution for the control of chafer grubs by Simon Piggott, Development Scientist, Becker Underwood, Littlehampton, UK.
Chafer grubs are the larval stages of the May / June beetle and are an increasing problem in turf throughout Europe. They
can create devastating damage to turf, either directly by the grubs feeding on roots or, indirectly by predators feeding
on the grubs. When grubs feed on roots they create characteristic yellowing of the turf and in severe cases damaged turf
can easily be rolled back since much of the root system has been severed (see plate 1).
High infestations of grubs in the soil provide a very attractive food source for predators such as badgers, foxes and
crows. These predators can focus on infested areas, tearing away turf to expose grubs and can completely remove patches
of turf over a wide area. In the UK there are a number of different species of chafer, however the most common is the
Garden Chafer (Phyllopertha horticola).
Pest BiologyThe Garden chafer follows an annual life cycle. Adults emerge in May/June and have a metallic green head/thorax and reddish-brown hairy wing cases. Once emerged they immediately mate and the females burrow in the ground to lay eggs and it has been reported that females will lay eggs up to a 4 km radius from her emergence site. However, there seems to be a tendency for chafer grubs to re-infest the same area annually. After 3 to 5 weeks later the eggs hatch into small larvae which have legs and are characteristically ‘C’ shaped with a white body and a reddish brown head. The grubs move up to the soil / turf interface and stay close to the soil surface until mid-October when they move deeper in the soil during the winter. The grubs remain inactive until the following April when they pupate (Figure 2). Methods of Control
Chemical controls have been effective and economically attractive but recent moves to restrict the use of chemicals and also the preference to look for alternatives have led to the hunt for a biological alternative. Parasitic nematodes have been used for the control of other pests for many years and there are nematodes that are very good for controlling grubs in horticulture and for the home and garden sector. However, it has taken much research to develop a method for controlling chafer grubs in amenity turf where factors such as thatch and turf management need to be taken into account. Research over the past 3 years in the UK and The Netherlands has led to the development of Nemasys G based on the nematode Heterorhabditis sp. a species that has evolved to target pests such as grub larvae and that provides the perfect biological solution to the problem of Garden Chafer grubs. How do nematodes work?
These nematodes are natural predators of the pest and will only target insects, actively seeking out grubs in the soil and entering them through natural body openings. Once inside they release symbiotic bacteria, quickly killing the grub within 2 to 3 days. The nematodes reproduce inside the dead grub and release a new generation of infective juveniles which disperse in search of further prey. All nematode products are found naturally in the soils of the country within which they are sold and using nematodes, artificially boosts the numbers of nematodes in an area where there has been a large number of pests. This helps to reduce the number of pest insects in that area and after a period of time the number of nematodes falls back down to a background level. Since these nematodes are specific to insect pests, they are completely harmless to other organisms including plants (turf), wildlife, operators and course users. Development of a biological solution
Sites were found both in the UK and in The Netherlands to try out 3 different types of nematode to see which was better for garden chafer control. It was found that one nematode in particular gave consistent results when applied with enough water to allow it to penetrate through the thatch and down to the site where the grubs were living. Field Studies
In the UK, sites were found for testing of nematodes against the garden chafer, one at the Greater Manchester Police Force Training College and the other on the south coast at Seaford Head Golf Course. In total there were 5 trials sites in the UK and the results indicate that the Heterorhabditis megidis nematode was a very effective control measure for the grubs. Other nematodes were also tried but these failed to give sufficient control. The trial was replicated a further time in The Netherlands and this was undertaken on at Toxandria, a golf course near Breda. The best result, at Seaford, was achieved due to the application of the nematodes with rainfall although the results at the other sites were also applied to moist soils. Overall, the Heterorhabditis megidis nematode achieved a control that was consistent. Use of the nematodes reduced the level of grubs in the turf and in particular, Seaford Head site showed a significant reduction in the level of damage caused by the secondary predation which was normally noticed by staff and turf users. Targeting is the issue
Previous use of nematodes has shown that the application must be done to moist soil and if the soil moisture is maintained for approximately 2 weeks after application the control of the grubs pest will be greatly improved. One of the interesting features of the work highlighted the importance of the movement of nematodes through the thatch layer. It is known that the grubs are closest to the surface of the soil during the autumn (typically during August and September – see Figure 2) but there is often quite a thick layer of thatch that impedes the movement of the nematodes down to the soil level where the grubs are feeding on the roots. Therefore, nematodes are best washed through the thatch with plenty of water and use of a wetting agent aids in penetration (similar to the use of wetting agents to prevent dry patches). Summary
The use of nematodes for the control of chafer grubs has been proven with a UK isolated nematode and at a level that is consistent and provides reduction in secondary damage to turf. Important features of the use of nematodes include sufficient water to allow the nematode to move through the turf and thatch and also at the correct time of year to allow targeting of the grubs where the grubs reside. Providing adequate water and timing, chafer grub populations can be reduced and the food source for predatory animals diminished. Nemasys G is manufactured by Becker Underwood (Telephone; 01903 732323, www.beckerunderwood.com and is available through Avoncrop Amenity (tel;01344 426600) and Aitken’s Sportsturf (tel; 01977 681155) from the beginning of August 2003.
Plate 1. Damage caused to turf by the garden chafer grub.
Figure 1. Summary of 7 trials undertaken on three sites since 2001.
Figure 2. Movement of grubs in the soil during the year and when nematodes are best placed. [top] National Chafer Survey If your lawn is looking yellow or has birds and/or wildlife scratching it up you could hold part of the key to where one of Britain’s major lawn pests is active. A new website has been launched to track where chafer grubs are causing misery to proud lawn owners throughout the country. www.chafersurvey.co.uk, which was launched this week, shows how to recognise chafer grub damage, what the pest looks like and how to combat it. Homeowners can register their chafer outbreak quickly and easily without their information being used for individual marketing purposes. Chafer grubs were the number five pest in the RHS top pest enquiries in 2004 (source: www.rhs.org.uk/news/chafersurvey.asp). They can be found in specific areas throughout the country and the website is designed to collect partial postcode information so that the chafer hotspots can be identified. As leatherjackets can do similar damage, the site also gives information to identify that pest, so that there is no confusion. The site’s promoters, Becker Underwood, produce the Nemasys range of nematode pest controls and European general manager, Dr Graeme Gowling, explains, “Chafer grubs cause misery to proud lawn owners up and down the country, but as far as we know, no-one has a map showing where the pest is causing problems. With the public’s support, we can identify those areas and homeowners can find out how to rid themselves of the problem.” Chafer grubs are creamy coloured and about 1.5 cm (0.6 inch) in length, have distinctive legs and are found in the root systems of plants and lawns. They are often mistaken for vine weevil larvae but chafer grubs have legs, whereas vine weevil larvae do not. Chafer beetles emerge from the lawn in May/June and lay their eggs in the ground in two weeks. The eggs hatch into grubs feeding on the grass roots in August and September before burrowing deep into the ground. They then lie dormant deep in the soil before moving to the surface in the spring to emerge as beetles again. So log on to www.chafersurvey.co.uk to find out more about chafer grubs and to log any sightings. The website promoters emphasise that the data collection will in no way link back to the individual so there should be no concern about being targeted for direct marketing purposes. [top]
Press Information
Enquiries from the media should be addressed to Sue Hinton or David Saunderson of DSH PR on 01252 408820, or email
pr@dshpr.co.uk. Images are also available for use in publications on application to
DSH PR.
[top]