Volume 2, Issue 9 (October 2005)
Nozzle Formulation Interactions: Consequences for Spray Droplet Adhesion to Plant Surfaces
Tests were conducted with a widely used herbicide (glyphosate) that is available in a range of formulations and a selection of commonly used nozzle types [XR TeeJet, extended range flat spray tip (XR), Turbo TeeJet, wide angle flat spray tip (TT), AI TeeJet, Air Induction spray tip (AI)] and determined the rebound characteristics of each combination using a difficult-to-wet foliar crop target (cabbage), an easy-to-wet hairy weed (velvetleaf), and a difficult-to-wet weed (lambsquarters). The rebound was determined under standard spraying conditions in a track room using a “bounce chamber” constructed at The Laboratory for Pest Control Application Technology (LPCAT). The amount of spray liquid retained and reflected from the leaf surfaces was determined by weight. The data showed that there were no significant differences between the nozzles, but that formulation differences did occur and were a reflection of surfactant level in the spray mixture. There was a significant formulation X leaf interaction and leaf X nozzle interaction, but not a formulation X nozzle interaction.