The common armyworm Leucania convecta (Mythimna convecta) was a localised and sporadic pest of rice until the 2011/12 rice season, but since that time it has become a much more consistent and widespread problem, particularly in the Murray Valley.
The biggest impediment to crop establishment in flooded rice fields (aerial seeded and dry broadcast) is bloodworms and aquatic snails. These two pests can have a large economic impact on the crop by reducing plant population and/or delays in establishment and maturity leading to reduced yields.
Last year the Southern Riverina experienced a significant increase in wild duck populations. This was due to above average rainfall across most of the State, with several stations including Cobar and Griffith recording their wettest winter on record.
Snails in rice crops can be effectively managed through crop rotations, however this con icts with the need for farmers to minimise total farm water use by using water remaining in the soil pro le from the previous crop.
Bloodworms are the larvae of midges, and are major pests of aerially-sown rice crops. At least one preventative insecticide treatment has to be applied each season to protect seedlings during crop establishment.