Total Effort

The chart shows the total effort for each of the last five seasons, divided into the time spent in the Reserve, Bottom Pinnacle and North Kama paddocks.

Between 1 July 2018 and 30 June 2019, the total amount of effort deployed on weed control was 739 hours. A further 6 hours was spent on experimental treatments for weed control. Excluding the experiment effort, this was 6% (43 h) more than last season, and the second smallest total for the 9 years of records. The amount of time spent on the Reserve* itself (95% of the total) was 12% more than last season, and the third smallest on record. This comparatively low effort reflects a large decrease in available volunteer time as well as the effect of the drier than average season on weed growth.

[* Note: effort for the Reserve includes effort in the 2016 Extension, both in this season and in previous seasons.]

Despite the reduced effort in the last three seasons, the major target weeds on the Reserve have been controlled as effectively as in previous seasons, in part because effort in adjacent paddocks has been reduced and focussed instead on the Reserve and in part because of our increased efficiency as a result of ever-improving mapping of where each weed type is located. In addition we are slowly having a measurable, lasting impact on weed infestation for a number of weed types, reducing the effort required from year to year.

Effort for different weed types

This chart shows the total effort for each weed type across all paddocks.

This chart shows the total effort for each weed type and how that was distributed between the Reserve and neighbouring paddocks. The largest effort was spent on St. John's Wort (218 h, all but 2 h on the Reserve). The next most effort was for miscellaneous Broadleaf Weeds* (204 h, all on the Reserve), followed by African Lovegrass (63 h on the Reserve, 64 h total), Skeleton Weed (44 h, all on the Reserve), Verbascum (24 h on the Reserve, 43 h total) and Briars (33 h on the Reserve, 47 h total).

*miscellaneous Broadleaf Weeds includes Hoary Mustard, Prickly Lettuce, Nightshade, Tragopogon, Plantain, Flatweeds, Paddymelon and Sorrel.

The percentage of total effort for each of the top ten weed types (and the rest) on the Reserve is shown in the table.

Weeds for which there were large increases in effort compared with last season:

• Exotic grasses - more than doubled resulting from trials to control common grasses such as wild oats by slashing and dabbing;
• African Lovegrass - 60% more than last season, partly as a result of more volunteers skilled in identifying it;
• Misc. Broadleaf weeds - 43% more than last season as a result of a concerted effort at removal in Weetangera paddock in response to their vigorous resurgence following the 2018 hazard reduction burn.

Weeds for which there were large decreases in effort compared with last season:

• Saffron Thistles - 57% less than last season as a result of reduced prevalence;
• Capeweed - 56% less than last season as a result of reduced prevalence after the very dry winter;
• Verbascum - 27% less than last season, which was in turn 70% less than the preceding season; this is partly because the rainfall conditions were less conducive to the germination and growth of Verbascum than in the previous season (see Measuring the effectiveness of Verbascum control) but also reflects successful control;
• Briars - 21% less than last season as a result of their decreased prevalence following an intensive eradication campaign (see Indicators of a successful eradication of Sweet Briars) .

For the amount of effort spent on each weed type in each paddock, see relative prevalence of each weed type in each paddock.

This chart shows the comparison of effort for each weed type targeted in the Reserve across the last five seasons.

Comparison of effort for each weed type for the last five years

The chart to the left 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 years. Comparison of effort for the Reserve alone therefore provides a better indication of weeding effort required to control each weed type. To see the equivalent chart for the Reserve and neighbouring paddocks combined, open the comparison for the combined Reserve and neighbouring paddocks window.

While there are considerable differences in effort between seasons for some weed types, others are quite close. Notable is the continued decline in effort on briars suggesting that we are being successful in eradicating these (supported by a detailed analysis of a range of indicators). A similar decline can be seen for Saffron Thistles, the Thistles other than Saffron thistles grouping, and woody weeds. Effort on Saffron thistles and Paterson's Curse peaked in 2013-14; while these could be seasonal effects, it is hoped that the decreased effort required since then is the result of our control effort rather than seasonal effects. Similarly effort on Verbascum peaked in 2015-16. A detailed analysis suggests that this is the consequence of Verbascum prevalence being dependent on summer rainfall, but also that there is evidence that our weed control is having a permanent effect on Verbascum prevalence.

By contrast, effort on St. John's Wort shows no sign of decreasing.

For a more detailed discussion of season to season differences, see season comparison page.

Effort in different paddocks

The chart shows the total effort for each paddock, divided into the time spent using different weed control methods.

The chart to the left shows the total effort for each paddock, separated into the time spent applying each weed control method.

This chart is presented as total effort in each paddock. In order to judge relative levels of infestation by each weed type in different paddocks, the chart can also be viewed as the effort per hectare in each paddock for each weed type targeted. On that web page it can be seen, among other things, that Central, Dam, Kama and Southern paddocks generally received the most effort/ha (on the Reserve).

The chart shows the total effort in each year, divided into the time spent using different weed control methods.

Effort spent on different control methods

This chart shows the total effort in each year apportioned into the different control methods. The percentage effort is shown on the left hand axis and the absolute hours on the chart bars themselves.

The most obvious feature is the big increase in spraying after 2010-11, as we emphasised that as the preferable control method. The percentage of spraying declined slightly in the last two seasons because of a decrease in available time of accredited volunteers but still represents close to 50% of effort. Overall there has been a decrease in bagging after 2010-11 as the increased spraying allowed more effective control of weeds prior to maturity. For the first few years there was a steady decrease in grubbing as a control method as we aimed to minimise the soil disturbance causes by using this method, but its percentage has increased again in recent years though the hours of effort remains much smaller than in 2010-11.