|
Workrate
Predictor
Our method
divides the whole site into estimated areas of bad, medium,
and light infestation, and then averages out the density of
the weed problem in those areas. We do this by measuring 5'
X 5' sample plots in typical examples of those three grades
of weed density. We count the weeds in the plots (and average
them), to give us figures which we call 'the average density
per 25m.sq'. We sometimes count several plots of similar
density to arrive at this figure.
Each density
is given an estimated total area within the site (and of course
a site map can help with this). We can then refer to ourwork
rate predictor charts for the target weed, which will give
us the time that is taken by one man to clear one acre, at
various weed densities. They also offer a costing based on
£6 per hour.
Another method
is to take tools onto your site
and find out how long it takes you to clear a chosen area.
All jobs have variable conditions, affecting work rates, but
make sure you are practiced before you do the sums.
The repetitive nature of the work means the knack of using
a Lazy Dog Tool is usually acquired quite quickly before.
Other costs to consider
|
| 1) |
Allow
time for removal & burning/ hot-composting of weeds. |
| 2) |
Allow
30 minutes for paid breaks in a seven hour day (our
normal practice) |
| 3) |
Allow
for possible transport or accommodation costs of gangs |
| 4) |
Allow
for the cost of the tools. |
|
| Factors
affecting work rate |
| 1) |
Terrain:
Fastest on flat sites. Slower on steep and uneven
banksides. |
| 2) |
Length
& type of surrounding vegetation.
Fastest in well grazed grassland, in which weeds are
most easily located . Slower among thick vegetation. |
| 3) |
Soil
Moisture:
(this is usually essential). Fastest in cool air and
moist soil conditions. Slower in dry sunny weather. |
|
4) |
Fitness
& team spirit: Choose
a workforce that gets on socially and is
reasonably strong. |
| 5) |
Method
: be methodical and target areas for completion before
the breaks. We sometimes divide up flat or open sites
by driving a van up and down to leave wheelings that
give 4 or 5 metre corridoors of responsibility to each
gang member. |
|
| CLICK
A BULLETED ITEM FROM THE LIST BELOW TO VIEW THE WORK-RATE PREDICTOR
CHARTS FOR :
|
| Work
Rate Predictor - Ragwort |
|
Average
ragwort density per 25m2
|
Number
of plants extracted per minute*
|
1
acre * cleared (mins)
slowest
rate
for
lower density
|
1
acre * cleared (mins)
slowest
rate
for
higher density
|
Cost
range @ £6.00 per hour of ragwort extraction over 1
acre
|
| 1-5 |
2-5 |
81 |
270 |
£8.10-£27.00 |
| 5-10 |
3-6 |
270 |
405 |
£27.00-£40.50 |
| 10-20 |
4-7 |
405 |
648 |
£40.50-£64.80 |
| 20-30 |
5-8 |
648 |
809 |
£64.80-£80.90 |
| 30-40 |
6-9 |
809 |
1079 |
£80.90-£107.90 |
| 40-50 |
6-10 |
1079 |
1349 |
£107.90-£134.90 |
|
<<BACK
*
Number of plants extracted per
minute based on timings during a 7hour day with 15 minute rests
every 2hrs and an hour lunch break with a relatively fit, tool
operator.
*( Multiply
by 2.47 for man hours per hectare )
Figures based on working field trials and contracts which
have been on going since 1998.
Compiled by
J.Trevelyan BSc (Hons) Plant and Soil Science. University
of Aberdeen
.
|
| Work
Rate Predictor - Docks |
| for
site specific work-rates, using the Lazy Dog
The size
and age of dock plants, together with ground and surrounding
vegetation, all influence working rates.
|
| 1) |
Seedling
docks - one year old. Smaller less well established
plants with tap root less than an inch in diameter.
Moist conditions. Easily visible. |
| 2) |
Mixed
seedling and one to five year old docks. Well established
mature dock plants with well formed, often forked tap
root between 1-2 inches in diameter. Moist conditions.
Easily visible. |
| 3) |
Mostly
older or larger established docks often growing in multi-stem
clusters with multiple, large 1-4 inch diameter forked,
tap roots. Moist conditions. Easily visible. |
|
|
Dock type |
No of docks extracted per
minute |
Man hours to extract docks
from 1 acre * at different densities
|
| 5
per 25m2 |
10
per 25m2 |
20
per 25m2 |
| 1 |
4 |
3.3
hrs |
6.7
hrs |
13.3
hrs |
| 2 |
2 |
6.7
hrs |
13.3
hrs |
26.7
hrs |
| 3 |
1 |
13.3
hrs |
26.7
hrs |
53.3
hrs |
|
<<BACK
*( Multiply by 2.47 for man hours per hectare )
Figures
based on working field trials and contracts which have been
on going since 1998.
Compiled by
J.Trevelyan BSc (Hons) Plant and Soil Science. University
of Aberdeen
.
|
| Work
Rate Predictor - Spear Thistle |
| for
site specific work-rates, using the Lazy Dog |
|
Average
thistle density per 25m2
|
Number
of plants extracted per minute*
|
1
acre * cleared (mins)
Range
- from slowest rate at low density to slow rate for
high density
|
Cost
range @ £6.00 per hour of thistle extraction over 1
acre
|
| 1-5 |
3
- 6 |
54
- 135 (mins)
|
£5.40
£13.50
|
| 5-10 |
6
- 10 |
135
- 202 (mins) |
£13.50
£20.20
|
| 10-20 |
8
- 12 |
202
- 324 (mins) |
£20.20
£32.40
|
| 20-30 |
10
- 14 |
324
- 486 (mins) |
£32.40
£48.60
|
| 30-40 |
10
- 14 |
486
- 648 (mins) |
£48.60
£64.80
|
| 40-50 |
10
- 14 |
648
- 809 (mins) |
£64.80
£80.90
|
|
<<BACK
*( Multiply by 2.47 for timings/ costs per hectare )
Figures
based on working field trials and contracts which have been
on going since 1998.
Compiled by
J.Trevelyan BSc (Hons) Plant and Soil Science. University
of Aberdeen
.
|
| Controlling
Canadian or Creeping thistle with the new Chisel Hoe
|
| (designed
& made by Lazy Dog Tools Ltd) |
|
Average
creeping thistle density per 25m2
|
Low
and high total number of plants per 1 acre (4047m2)
|
Number
of plants extracted per minute*
|
1
acre * cleared (mins)
Range
- from slowest rate at low density to slowest rate at
high density
|
Cost
range @ £6.00 per hour of creeping thistle extraction
over 1 acre
|
| 1-5 |
162-809 |
5-10 |
32
- 162 (mins)
|
£3.20-£16.20 |
| 5-10 |
809-1619 |
10-15 |
81
- 162 (mins) |
£8.10-£16.20 |
| 10-20 |
1619-3238 |
15-20 |
108
- 216 (mins) |
£10.80-£21.16 |
| 20-30 |
3238-4856 |
20-25 |
162
- 243 (mins) |
£16.20-£24.30 |
| 30-40 |
4856-6475 |
25-30 |
194 - 260 (mins) |
£19.40-£26.00 |
| 40-50 |
6475-8094 |
25-30 |
260
- 324 (mins) |
£26.00-£32.40 |
| 50-100 |
8094-16188 |
25-30 |
324-648
(mins) |
£32.40-£64.80 |
| 100-200 |
16188-32376 |
25-30 |
648-1295
(mins) |
£64.80-£129.50 |
| 200-300 |
32376
- 48564 |
25-30 |
1295-
1943 (mins) |
£129.50-£194.30 |
| 300-400 |
48564
-64752 |
25-30 |
1943
- 2590 (mins) |
£194.30-£259.00 |
| 400-500 |
64752
- 80940 |
25-30 |
2590-
3238 (mins) |
£259.00-£323.80 |
| 500-600 |
80940
- 97128 |
25-30 |
3238
-3886 (mins) |
£323.80-£388.60 |
| 600-700 |
97128
- 113316 |
25-30 |
3886-
4533 (mins) |
£388.60-£443.30 |
| 700-800 |
113316-
129504
|
25-30 |
4533
- 5180 (mins) |
£453.30-£518.00 |
|
<<BACK
These higher figures are rare, sometimes encountered in cultivated
land where repeated & deep rotovation had been tried. (a
big mistake).Rotovators can only be used very carefully on the
surface inch of soil, with this weed |
