Herbicide Application Methods – Re-thinking Delta T
Delta T is the relationship between temperature and relative humidity that gives a score for deciding the best times to apply sprays on crops.
John Both from NuFarm at the Eyre Peninsula Agricultural Research Foundation (EPARF) members day held at the Minnipa Agricultural Centre discusses Delta T for making decisions about your herbicide application methods. In the summer Delta T can often be high during the day, resulting in spraying occurring in the morning or evening. These are times when inversion layers are most likely resulting in drift issues.
Research has shown that high Delta T’s in summer can still give good weed control so long as the weeds are actively growing. Delta T is a good guide but you can consider other factors when making spraying decisions to reduce the risk of drift and achieve good weed control.