Herbicide resistant weeds are a major threat to crop production, with the broadleaf species wild radish (Raphanus raphanistrum), sowthistle (Sonchus oleraceus), and Indian hedge mustard (Sisymbrium orientale) being of concern in Australia. Surveys of south-eastern Australia conducted over a 5-year period found significant levels of resistance to Group 2 sulfonylurea herbicides with 66% of sowthistle, 34% of Indian hedge mustard and 16% wild radish populations resistant to this group. Lower levels of resistance were found to four other herbicide groups

This viewpoint critiques four papers that presented positive conclusions regarding the efficacy of a range of biostimulants to mitigate the effects of pasture dieback in Queensland, Australia. We argue that many methods used were inappropriate or poorly described, the statistical analyses are largely invalid, and the conclusions drawn do not align with the data presented. We conclude the four publications do not present any compelling evidence for any agronomic benefits of the biostimulants tested, and the authors’ conclusions are over-optimistic and misleading.