Producer perceptions of changing occurrence and successful control methods for 'Nassella trichotoma' and 'N. neesiana'

Abstract

A postal survey targeting sheep graziers across southern Australia was undertaken in January 2004. A total of 937 landholders responded to the questionnaire. Among other things, the survey gleaned information on producer perceptions of changing occurrence of pasture weeds and successful control methods. 'Nassella trichotoma' (serrated tussock) and 'N. neesiana' (Chilean needle grass) were reported as weeds by 14.5% and 2.2% of respondents, respectively. Maps showing the distribution of the reported occurrences of both species are given. Serrated tussock showed significant variation between regions in the level of occurrence and the degree to which the perceived problems had changed. Chilean needle grass was reported as an increasing problem by the majority of respondents who had the weed on their properties. Some 92.9% of respondents who had serrated tussock and 81.3% who had Chilean needle grass had attempted to control these weeds. For full time graziers, the most commonly reported control methods for Chilean needle grass were spot spraying (84.6%), cultivation (46.2%) and chipping (38.5%). Of the respondents using these techniques, 54.5% reported success with spot spraying, 33.3% with cultivation and 40% with chipping. Many of the respondents appear to be failing in their attempts to manage this weed.