Comparison of effort for each weed type for the last five seasons
This chart shows the amount of effort in the Reserve in each of the last five seasons for each of the weed types targeted. The comparison here is restricted to the Reserve because of the inconsistent weed control in the neighbouring paddocks over those seasons. Comparison of effort for the Reserve alone therefore provides a better indication of weeding effort required to control each weed type. The equivalent chart for the whole area can be seen by clicking the following link: comparison for the combined Reserve and neighbouring paddocks.
While there are considerable differences in effort between seasons for some weed types, others are quite close. Consistent trends can be seen in the decline of effort required for briars and for other woody weeds suggesting that we are being successful in eradicating these.
Briars, which have been closely monitored, decreased steadily from an average density across the Reserve of 44 briars/ha in 2012-13 to 1.1 briars/ha in 2020-21 (see the detailed analysis for a range of indicators of briar eradication success).
Effort on Verbascum peaked in 2015-16 and then tailed off until the 2020-21 season. It is believed that this is strongly linked to rainfall. A detailed analysis up to 2019-20 suggested Verbascum prevalence was primarily dependent on summer rainfall, but also that there is evidence that our weed control was having a permanent effect on Verbascum prevalence. This analysis will need to be reviewed in light of the 2020-21 season.
By contrast, effort on the category of miscellaneous broadleaf weeds shows no sign of decreasing, though this is in part due to the deployment to this category of resources previously used on other weed types.
Otherwise, effort is quite variable from season to season depending on seasonal conditions and available effort.
For a more detailed discussion of season to season differences, see season comparison page.