Friends of The Pinnacle   weeding effort  2010 - 2011  
home page what's on news


search tips advanced 
site search by freefind


An important aspect of the Weed Management Plan is monitoring and reporting on our interventions. This includes monitoring our weeding effort to know how our resources have been deployed, and to compare it with the requirements projected in the plan.

Data on this page is for the year 1 July 2010 to 30 June 2011. Weeding effort for the current year, updated monthly, can be found at weeding effort. The data is accumulated from 1 July 2010, when detailed monitoring commenced, to 30 June 2010.

Related pages: 2010-2011
weeding maps
effort for each weed species against targets
effort for each weed species across all paddocks
monthly effort distributions

In addition to the effort spent directly managing weeds, several hundred hours were spent on the Native Grass Restoration Project, which we hope will eventually contribute to reducing the amount of direct weeding effort required.

Tip: Hover mouse over chart thumbnail to see full size chart.

The chart shows the total effort for each paddock, divided into the time spent grubbing and pulling weeds and that spent spraying.

Total Effort
Between 1 July 2010 and 30 Jun 2011, the amount of effort deployed in weed management has been 943 hours:

Grubbing, pulling and bagging: 526 hours
Spraying: 186 hours
Slashing and Scything: 231 hours

The total effort for June was 69 hours (compared with 56 in May, 58 in April, 80 in March, 113 in February, 202 in January, 105 in December, 92 in November and 22 in October).

The chart shows the total effort for each paddock, separated into the time spent grubbing and pulling weeds, that spent spraying, that spent slashing with brushcutters and scythe, and that spent cutting and bagging seed heads.


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

Effort for different weed types
This chart shows the total effort for each weed type across all paddocks. Most of the effort in May was spent tackling Verbascum (30 h), followed by thistles (18 h) and followed by woody weeds(21 h, 9 of which was briars).

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

To see how the effort for each weed type is distributed across all paddocks, see weed effort distribution.


Actual effort compared with the estimated effort required, as functions of time since 01 July 2010.

To see our performance against the targets for each weed type, click here.

Comparison with targets
The Draft Weed Management Plan estimated the amount of effort that would be required to effectively control priority weed species on The Pinnacle Nature Reserve. The actual effort is compared with this target in the accompanying chart.


The total for the year of 943 hours was 21% short of the estimated requirement. Our actual effort kept pace with the requirement estimated in the Weed Plan in all seasons except Spring. In that season the estimated effort required increased dramatically to 150 hours/month but the actual effort remained at Winter levels of about 40 hours/month. The effort "lost" in Spring was never recovered, but since December the effort for each month has been near or above the target value.


Species targets Species targets
Actual effort compared with the estimated effort required, as functions of time since 01 July 2010.

Comparison with individual weed species targets
These are shown in detail on the species target page, but are summarised in the barchart to the left (hover over to enlarge).

For many species we have exceeded the targets for the period to date. This is obvious for Saffron Thistles, the orange bar, which is 150% greater for the achieved record than the target estimate, other Thistles (red; 235% greater) and Patersons Curse (green; 150% greater). Effort for St Johns Wort (dark red) and African love grass (dark blue) are right on target.

For other priority species, however, we have failed to meet the target. The key examples are Verbascum (the far right bar; 83% below target) and Horehound (60% below). Given the levels of effort required for other priority species, these had to wait, but started receiving attention during March and April, with a significant spraying campaign for Verbascum until it got too cold, followed by grubbing in May. Some spraying of Horehound was also carried out, but it is not growing actively enough to be effective.

To counter this, a number of species not included in the weed plan have assumed importance this season (Hoary Mustard, Woody weeds, Prickly lettuce, Nightshade and assorted broadleaf weeds), and over 100 hours effort has been spent on those.

A note about targets

The targets defined in the Weed Management Plan were the amount of effort required to provide reasonable assurance that all plants are treated, and that no weeds set seed.

The targets were estimated on the basis of:

  1. a survey of size and density of weed patches between October and December 2009, and
  2. tests of the effort required to control a given area/number of each weed.

This was a practical way of estimating targets, but subject to a number of limitations:

  • Spring rainfall in Canberra in 2009 (118 mm) was the 16th driest on record, and 30% below average. Weed germination and growth in 2009 would therefore be expected to be less than average.
  • Not all weeds were visible at the time of the survey, many being hidden by other weeds, particularly the early maturing grasses.
  • Not all weeds may have germinated at the time of the survey.

In contrast, the 2010 Spring was 15th wettest on record, with 255 mm of rain, twice as much as 2009. The germination and growth of weeds would be expected to be much greater in 2010 than 2009, and therefore the targets for 2009 likely to be less than those required to control all weeds in 2010. This is particularly so with the continuation of rainfall and mild conditions in December (the second wettest on record), prolonging the germination and growth of weeds.

What the effort data tells us ...

  • Our baseline effort (one weekly and one two-weekly weeding event of about 3 hours each, attended by 3 people - 58 hours/month, or 700 hours/year) is not sufficient to meet the targets in the Weed Management Plan, and certainly not sufficient to cope with the quantity of weeds experienced this Spring/Summer.
  • Wet weather and members' unavailability means that the baseline effort is sometimes not met, as in Spring 2010, so the effort is even less than baseline. This caused us to fall behind the target in Spring, and we have yet to catch up.
  • We therefore need to increase team size and weeding frequency with special events such as that held on Australia Day, when 40 hours effort was put in by 14 members, a record for a single day.
  • In every month since October, however, we have met or exceeded the baseline effort, thanks to some stellar performances by individuals, and the answer of 28 members to the call to arms to cope with the intense weed threat this year.
  • In January we exceeded the target by a creditable 25% with 202 hours of effort for the month, equivalent to 6.5 hours for each day of the month. A massive 48 hours (or nearly 25% of the total for the month) was contributed by Bob Hodgson, largely thanks to his eager adoption of the "new" "old" technology of the scythe. The aforementioned Australia Day event also contributed significantly to January's result.
  • In contrast to Spring and Summer months, the weeding targets for the autumn and early winter months of March, April, May and June were easily achieved. Nevertheless, the effort applied was not sufficient to keep up with the weeds in a wet year such as this one. The autumn targets will need to be revisited when the Weed Plan is revised.
  • The long weed germination and growing season induced by this year's very favourable weather conditions have resulted in an extended season for saffrons and St Johns Wort (healthy young plants of which are still evident in June). This meant that effort was not able to be switched to later developing weeds such as verbascum as early as is desirable.
  • Weeds not identified in the Weed Management Plan because they were not present in large numbers in 2009 have required significant effort this year, notably Hoary Mustard and Prickly Lettuce.
  • Some treatment of highly invasive weeds, notably African Lovegrass, was carried out in the boundary areas of the park as a control measure to stop them spreading into the park. Only 7 hours of effort was recorded this year for this activity.

Using our experience to date, we will prepare a report at the end of the weeding season (July) to provide the basis for variations to the Weed Management Plan.


Amount of weeding effort for each weed type in each paddock
Hover your mouse over the paddock names on the map below to show charts of the effort for each weed type in each paddock, which shows the amount of effort for each weed type in each paddock. It also gives an indication of the prevalence of each type across different parts of The Pinnacle Nature Reserve, is so far as the effort is related to the need, and therefore to the severity of weed infestation.


To see how effort for each weed species is distributed across all paddocks, see weed effort distribution.


The chart shows the total effort for each paddock, divided into the time spent grubbing and pulling weeds and that spent spraying.

© Friends of The Pinnacle