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As an aid to more accurate
pasture assessment,
lifetimewool has
developed sets of photo
standards of different
pasture types and seasons.
At present there are photos
for annual clover based
pastures(WA & SA)
and High Rainfall Zone
(eastern Australia) pastures
in the green phase using
Feed on Offer (FOO).
Hardcopy booklets of FOO
photos are available for the
High Rainfall and Medium
Rainfall
(annuals) Zones are
availalbe free of
charge. Contact AWI
for your copy on +61
2 8295 3100 or Simon
Crump at
AWI.
Use these photos as a guide
only. More detailed methods
of assessment will give more
accurate results. Feed on
Offer (FOO) is measured
as kilograms of dry matter
per hectare. These levels
include all above ground
green plant matter.
For those using Herbage Mass
(HM) please see the
conversion details provided
here.
Tips for Assessment:
- Bare Ground
% - has a
big effect on the amount
of dry matter per
hectare.
- Density
- it is important to
feel how thick the
pasture is.
- Height
-usually autumn FOO is
at least twice that of
Spring FOO for the same
amount
- Grazing
Pressure -
this will affect how
dense the pasture is and
its height. Closely
grazed clover pastures
can be very high in FOO
for their height.
- Season
- pasture moisture
content rapidly changes
towards flowering and
senesence. This affects
the weight of the
pasture dramatically.
Perennial
and Annual mixed
pastures (High Rainfall
Zone)
There are four
steps involved
in pasture assessment for
the High Rainfall Zone.
1. Identify
thepaddock
the ewe mob will graze
during a selected
time period (10
- 30 days recommended).
Note: Where the ewe mob
will be rotated through
more than one paddock
within this time period,
an average FOO can be
calculated by assessing
FOO when the animals
enter and leave each
paddock.
eg. FOO
at entry = 2000 kg, FOO
at exit = 1000 kg,
average FOO = 1500 kg.
2. Determine whether
pasture is in
'green' or 'dry'
state .
Pasture is in a 'green'
state when it is in the
vegetative or early
flowering stage
(generally from the
seasonal break to
sometime in
spring). Once
plants have entered the
late flowering
stage the pasture
is considered to be in a
'dry' state. A
pasture will switch back
to a 'green' state when
new plant growth
commences following the
break, by which time
'dry' feed reserves
generally have been
eaten back considerably
due to grazing over
summer.
With a pasture
containing both 'green'
and 'dry' feed, the
contribution of each
pasture component to ewe
energy intake generally
needs to be
considered.
However, the
contribution of the
'dry' component can be
ignored if 'green' FOO
is greater than 1000 kg
or 'dry' FOO is less
than 400 kg. In
this case, only the
green component is
considered when
calculating ewe energy
intake
3. Assess
pasture quantity on 10
to 15 random
locations
across the paddock.
Use the 'FOO Photo
Gallery' as a reference
to make pasture quantity
assessments. After
recording quantity
assessments, add all the
values together and
divide by the number of
assessments to give an
average pasture quantity
for 'green' FOO.
These
photos are at a
resolution for on
screen
viewing. To
download a hard copy
of these pictures,
please click on the
image.
4.
Evaluate pasture
quality by
estimating the pasture
composition in paddock.
For
'Green' feed: To evaluate
pasture quality of herbage
in the 'green' state, the
assessor needs to choose one
of four pasture quality
descriptions. These
descriptions are summarised
in the following table:
|
Pasture
Quality
for
mixed
swards
|
|
Quality
Descriptions
|
Digest
Green
(%)
|
Digest
Dead (%)
|
Legume
(%)
|
Dead
(%)
|
Characteristics
|
|
Very
High
|
75%
|
45%
|
60%
|
10%
|
Consists
of
a
high
proportion
of
legumes
such
as
sub-clover,
white
clover,
medics
or
lucerne.
Grass
pasture
species
that
present
are
generally
highly
digestible
perennials.
There
is
a
very
low
proportion
of
low
digestibility
annuals
and
'dead'
pasture
within
the
sward.
|
|
High
|
75%
|
45%
|
30%
|
10%
|
Comprised
of
predominantly
highly
digestible
perennial
grass
species
such
as
ryegrass,
phalaris
or
fescue.
Have
a
reasonable
proportion
of
clover
present
(around
30%).
Very
low
amounts
of
'dead'
plant
material
in
the
pasture
sward.
|
|
Medium
|
70%
|
45%
|
15%
|
20%
|
Typically
consists
of
a
mix
of
highly
digestible
perennial
grasses
and
moderate
to
low
digestibility
annual
grass
species.
The
legume
content
of
pasture
species
within
the
sward
is
typically
low
at
15%.
The
amount
of
'dead'
plant
herbage
generally
around
20%.
|
|
Low
|
65%
|
45%
|
5%
or
less
|
Up
to
50%
|
Typically
has
a
large
proportion
of
low
digestibility
species
(e.g.
Onion
grass,
silver
grass).
May
contain
a
proportion
of
moderate
digestibility
species
(e.g.
Cocksfoot,
barley
grass).
Very
low
clover
content.
May
also
have
high
levels
of
dead
plant
material
in
the
sward.
|
|
For
'Dry' feed: As a general
rule, when pasture begins to
'hay-off' (during late
flowering), digestibility of
feed is around 60%,
depending on the pasture
species
present. Depending on
seasonal conditions, this
period may extend beyond the
break into winter.
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