Failing to spray for Leatherjackets (Tipula spp) during the UK's traditionally wet autumn presents an unnecessary threat to greens.
Bayer's Technical Support Manager, Dr Colin Mumford recommends a routine spray with a turf insecticide, such as Merit® Turf at this time of year to nip any problems in the bud.
"Leatherjackets have the potential to cause serious damage to turf playing surfaces and can present a tough repair challenge," says Colin. "The adults lay their eggs in the turf," he explains. "When hatched the larvae essentially chew the roots which can kill the turf. In extreme cases, the turf surface can actually come away from the ground and peel off, like a carpet being lifted. As the weather gets colder, this damage can be exacerbated by birds and animals digging up the turf to feed on the leatherjackets."
Fine sports turf is most at risk, especially golf greens and tees where a smooth, even playing surface is essential. "At this time of year, greenkeepers are trying to establish a strong root system going into the winter and the removal of any potentially problematic pests is very important in order to safeguard for the following year," says Colin.
He explains that if the autumn is very dry, Leatherjacket eggs will perish due to desiccation. "A very dry autumn in this country is quite rare. Invariably parts of the UK will experience rain on some level allowing the eggs to survive." Colin stresses that during the early stages after egg hatch it's imperative that the larvae are sprayed while they're immature and still close to the surface.
"The treatment becomes increasingly less effective as the larvae move deeper into the root zone as surface temperatures drop and as the larvae's skin hardens." For this reason he advises that the most effective method of gaining complete control is to apply an insecticide treatment like Bayer's Merit® Turf now when the larvae are most susceptible to the treatment. This tends to be in late summer and early autumn and can be anytime from the middle of September and throughout October.
Colin adds that application technique is also important. "Merit® Turf needs to be applied evenly across the whole turf area before being thoroughly irrigated. Watering-in is critical for successful control and to move the active ingredient through the thatch and into the root zone of the turf."
Merit Turf can be purchased from the Pitchcare Shop.