Ecogrow

Sod Webworm Herpetogramma licarsisalis

Turf | Field Crops | Glasshouses | Control | Hint

Background

The adult Sod webworm is a pyralid moth and which is generally believed to have originated from southeast Asia. The name comes from the appearence of ‘webbing' associated with their feeding. The Sod webworm is widely distributed throughout southeast Asian countries and the Hawaiian Islands where it was first found in 1967. In Australia, the Sod webworm is throughout the northern tablelands and south eastern, coastal Queensland and along the north and central coasts of New South Wales.

The ecology of the sod webworm has not been fully investigated in Australia. Host grasses in Australia include Common Couch, Kikuyu and Queensland Blue Couch. Other grass species are hosts in Hawaii.

Damage

In New South Wales the larval stage causes the majority of damage during late summer and autumn. In northern Queensland damage has been recorded in September and from December to March (Champ, 1955). The larvae are foliage feeders and often leave behind the ‘frass' (faecal pellets). Pupation is known to occur in the soil within a woven silken case.The damage shows up as small dead patches of grass among the normally growing grass. Sod webworms prefer sunny where it is hot and dry. Heavily shaded turf is seldom attacked by the larvae.

Control

Biological with ENs
This product is designed for surface treatment only. Spray at dusk when pests are evident and damaging sunlight is at a minimum. Area to be treated should be thoroughly moistened before applying to ensure environmental conditions are favourable for the nematodes activity and survival.

Apply nematodes uniformly to ensure that each square metre receives the same amount of nematodes. Use a two-way spraying pattern, applying half of the total solution in each direction.

Apply Turfnem 2 at a rate of ten tubs per hectare apply through a boom spray with a minimum of 500 litres of water per hectare.

This nematode species is known as Steinenema carpocapsae which has a high efficacy on cutworm and therefore can be controlled a lower rate per hectare.

Hint
Sample suspected site using a turf doctor or golf hole changer to a depth of 50mmm min. Gently separate soil and thatch to determine the presence webworms. Alternatively flush suspected sites using a pyrethrum and water at a rate of 25:1. To bring adult sod webworms to the surface.