Trifluralin is one of the most widely used herbicides in Australia. Despite it being in use since the 1970s, it is surprising how many myths exist around how it works. Eureka! has conducted dozens of experiments with trifluralin. Over the next couple of newsletters I will share some of our findings with you. In this article I will cover how trifluralin kills weeds, its movement through the soil as a gas, where it is absorbed into the plant and the proportion that is lost to volatilisation and UV degradation. Please note that the scientific methods used in the experiments described here are too lengthy for this article. If you want more information on them please contact me.