TECHNICAL U P D AT E
By Dr Minshad Ansari CEO Bionema
THE CHAFER GRUB’S NEMESIS
With many chemicals now removed from the groundsman’s armoury, nature has its own answers to combat chafer grubs and leatherjackets – solutions that are equally effective, greener and cheaper
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roundskeepers rightly consider chafer grubs and leatherjackets as major pests. Damage to grass roots caused by their larval feeding is most severe during autumn and again in the spring, as soil temperatures rise. Agriculture and environmental consultancy ADAS suggests that lost income on a racecourse affected by the pests’ damage could amount to £605,000.
But products using beneficial insectparasitic nematodes (roundworms), which are completely harmless to humans and the environment, can be an effective alternative and, in many cases, do show increased kill rates over ‘traditional’ pesticides. These nematodes have been commercialised to control various insect pests currently affecting the agricultural, horticultural and forestry sectors, and are now available to support the turf and amenity market. After a Bionema programme of chafer grub control at The Grove hotel and golf resort in Hertfordshire, golf course and estate manager Phil Chiverton said: “We saw a more than 80 per cent reduction in chafer grubs in the first year and further improvements in year two, while at the same time doing less harm to the environment and saving money compared with chemical applications.”
HOW DO NEMATODES WORK?
An infestation of chafer grubs
26 THE GROUNDSMAN May 2019
Nematodes actively search for insect larvae within soil and growing media. They enter the insect via natural openings and release friendly lethal bacteria, which kill the insect within 24-48 hours, depending on host species. Then they reproduce; within two weeks, approximately 50,000-100,000 new