Fall armyworm moths are continuing to show up in Northland traps, and a large population of tropical armyworm has been causing confusion.
- FAW moths are continuing to show up in Northland traps, although numbers have slowed. A winter surveillance strategy is currently being initiated for the winter in Northland.
- There has been a large population of tropical armyworm in the North Island. While not to be ignored, it is easy to mistake it for FAW. Watch Colin Hurst (Federated Farmers) and Ivan Lawrie (FAR) setting the story straight here.
- We are now in the sixth week of the transition to a long-term management phase. This has been an industry-led management transition.
- There is a total of 140 confirmed reports of FAW across NZ.
- In many areas poor weather around harvest-time has shown large amounts of lodging, shedding/shattering, resulting in volunteer maize, a potential winter host for FAW.
- As temperatures get colder, the life cycle has begun to slow. However it is important to stay vigilant and scout harvested paddocks, and any neighbouring paddocks, as FAW will target a large variety of crops. They have been observed on ryegrass and clover in a harvested maize paddock. Crop residues should not be overlooked either.
- Any information on new host plants will be welcomed as we begin to understand overwintering capabilities and green bridges. Significant observations are important, so please record them and inform us.
- The insecticide Sparta™ is on label for aerial and ground applications for controlling fall armyworm on maize and sweetcorn crops. Consult with your advisor.
- Avoid the use of insecticides that are ineffective on fall armyworm and potentially harmful to beneficial insects such as parasitic wasp Cotesia sp. which will help contain the numbers.
For the latest identification guides click here and MPI Website here, or contact Ivan Lawrie ivan.lawrie@far.org.nz or Ash Mills ashley.mills@far.org.nz
For other useful tools and guides on detection and identification, consult the FAR website.
Photo: Scouting winter oats on the West Coast. The paddock had a reasonable FAW population at the time of the maize harvest. Three moths have been trapped since.
Graph: Courtesy of Jenny Dymock.