To evaluate banded wetting agent (SACOA ‘Irrigator’) for crop establishment and yield on non-wetting soils in the West Midlands.

• This set of trials indicates that SACOA ‘Irrigator’ banded wetting agent can improve crop establishment and grain yield but that responses can be highly variable. The 27-32% yield increase seen in 3 of the trials is very encouraging. Based on these and other trials it can be suggested that banded wetting agents are most likely to be effective when:
• Soils are moderate to strongly repellent and there are few residual roots form the previous year’s crop; and points and tines are used for seeding.
• Banded wetter is applied in a consistent stream to the base of relatively stable furrows. Collapsing furrows, furrow infill and a disrupted band of wetting agent can reduce efficacy. Presswheels with a more rectangular cross section tend to rip up furrow walls and the disturbed soil buries and mixes banded wetting agent. ‘V’ section or round section presswheels with no deep flange reduce such problems.
• The banded wetting agent kit needs to be robust and reliable and needs to accurately apply the wetting agent in a continuous stream into the base of the furrow
• Crops sown early into dry or partially dry soil before opening rains derive more benefit from banded wetter. Banded wetting agents are typically less beneficial when used later in the sowing program when there has already been rain and the soil has started to wet up.
• Growers already using wetting agents are tending to modify their usage of banded wetter to better match the likelihood of significant benefits. Some growers only use banded wetter for the dry seeding or early part of the program and don’t use it later in the program after there has been more rain.  Other growers are planning to use higher rates of banded wetter early in the program but then aim to reduce the rates when sowing later in the season. Both of these strategies will reduce cost while maximising the opportunity for benefits to crop establishment and yield. Current research in the state is showing that different banded wetting agent products can have a wide range of effects of crop establishment and especially on yield. DAFWA is continuing to research a range of products to help growers evaluate which types of banded wetting agent are more suitable for their farming system.