DEPARTMENT OF
PRIMARY INDUSTRIES
Chilean needle grass (Nassella
neesiana) Integrated grazing for
success
Charles Grech
2/11/05
DPI Agricultural weeds
DEPARTMENT OF
PRIMARY INDUSTRIES
The problems
• Chilean needle grass (Nassella
neesiana)
– Low feed value & physical damage
to livestock when in seed
– replaces more productive improved
pasture species
– invades native grasslands and
conservation zones
– Seeds dispersed by adhering to
machinery & animals
– Stem seeds and basal cleistogenes
2
DEPARTMENT OF
PRIMARY INDUSTRIES
Grazing management PhD
• Two National projects:
– Chilean needle grass Regional Best Practice
Management
– Grazing management for long term utilisation and
control of Chilean needle grass
• To determine the stock density, species of grazer and time of
grazing to maximise animal production
• Supervisors
• Dr Brian Sindel - The University of New England, Armidale
• Dr David McLaren - Department of Primary Industries,
Frankston
• Dr David Chapman - The University of Melbourne, Parkville
3
DEPARTMENT OF
PRIMARY INDUSTRIES
Trials underway...
• Regional Best Practice Management
– NSW & Vic
• Feed evaluation of Chilean Needle Grass
– fertiliser and clipping
– spraytopping
• Reducing seed production
– Comparison of stock class for Chilean Needle
Grass grazing
– Time of Burning
– Time of Slashing
• Competition and Selective manipulation
– Pasture Species Competition
– Soil Fertility and pH
– Herbicide wiper
4
DEPARTMENT OF
PRIMARY INDUSTRIES
Chilean needle grass
Regional Best Practice Management
•
The majority of knowledge concerning CNG comes from a study
undertaken at one location (near Armidale, NSW)
– seed production appeared to be sensitive to rainfall,
– interaction of temperature and rainfall.
– This makes the generalisation of management recommendations from
one region to the next questionable
5
DEPARTMENT OF
PRIMARY INDUSTRIES
•
•
Chilean needle grass
Regional Best Practice
Management
Four regional trial sites
– Glen Innes NSW
(Property of Col & Andrew Say ‘Euroa’)
– Goulburn NSW
(Property of Tony and Donna Kent ‘Dambreezi’)
– Toolleen Vic
(Property of Roger & Brian Hickson )
– Greenvale Vic
(Property of Ian & Margaret Souter ‘ The Elms’)
Sites managed with regional staff - DPI NSW & VIC
– Lori McWhirter
– Jeff Lowien
– Natasha Baldyga
– Brad Westhead
6
DEPARTMENT OF
PRIMARY INDUSTRIES
Chilean needle grass
Regional Best Practice
Management
• Treatments (applied autumn 2003 onwards)
– Herbicide (Glyphosate; non selective &
spraytopping, Flupropanate)
– Sheep grazing (strategic grazing, set stock,
lockup)
– Resowing (pasture, cropping)
Greenvale, Toolleen, Goulburn
Glen Innes
Treatment
1
2
3
4
5
6
7
8
9
10
11
12
Grazing
Spray
Resow
Set Stock
None
None
Set Stock Selective (Glyphosate)
None
Set Stock
Glyphosate
Sow pasture
Set Stock
Glyphosate
Sow pasture
Strategic Selective (Glyphosate)
None
Strategic
Glyphosate
Sow pasture
Strategic
Glyphosate
Sow pasture
Set Stock
Spray-top
None
Strategic
Spray-top
None
Strategic
None
None
Set Stock
Flupropanate
None
Strategic
Flupropanate
None
Crop
No
No
No
Yes
No
No
Yes
No
No
No
No
No
Treatment
1
2
3
4
5
6
7
8
9
10
Grazing
Set stock
Set stock
Lock up
Lock up
Lock up
Lock up
Strategic
Strategic
Strategic
Strategic
Fertiliser
No
No
Yes
Yes
No
No
Yes
Yes
No
No
Spraying Resow
None
No
Flupropanate No
Flupropanate Yes
None
Yes
Flupropanate No
None
No
Flupropanate Yes
None
Yes
Flupropanate No
None
No
7
DEPARTMENT OF
PRIMARY INDUSTRIES
Effect of spray type on CNG Basal cover Toolleen d569
25
20
No spray
15
Glyphosate & Sow
10
5
Flupropanate
4
3
0
Effect of Spray type on CNG Basal
cover - Greenvale d601
20
% Cover
% cover
20
16
15
10
No spray
Glyphosate
7
Flupropanate
5
0
0
8
DEPARTMENT OF
PRIMARY INDUSTRIES
Effect of grazing regime on desirable
perennial grass basal cover in
glyphosate plots - Toolleen d569
24
Lockup & Resow
20
11
Strategic graze &
Resow
10
0
Effect of grazing regime on broadleaf
weeds in flupropanate plots - Greenvale
d601
20
% cover
% cover
30
15
Set stock grazing
10
Lockup
5
0
Strategic grazing
9
DEPARTMENT OF
PRIMARY INDUSTRIES
• Strategic grazing after Flupropanate
application (Winter 2003)
– significantly less CNG than set stock
plots - Toolleen Dec04
Set
stock
Strategic
Winter 2004
Spring 2004
Autumn 2005
1
0
DEPARTMENT OF
PRIMARY INDUSTRIES
Chilean needle grass
Regional Best Practice
Management
• Trends so far…
• Flupropanate
– reduced CNG cover
– proportional to grazing
• broadleaf weeds
• Glyphosate (& sow)
– reduced CNG
– increased perennial
1
1
DEPARTMENT OF
PRIMARY INDUSTRIES
Feed evaluation of Chilean needle
grass Fertiliser addition & Clipping
• Low feed value in contrast with producer observations
• Feed value quantified throughout growing season (FeedTest)
– compared to cocksfoot (Dactylis glomerata)
• Trial conducted at Greenvale Victoria (Property of Ian Souter)
spring 2003 to winter 2005
1
2
DEPARTMENT OF
PRIMARY INDUSTRIES
Feed evaluation of Chilean needle
grass Fertiliser addition & Clipping
• Treatments
– Clipped regrowth Vs unclipped growth
– Fertiliser addition
Treatment
1
2
3
4
5
A 250kg/ha
B 200kg/ha
Phosphorus
(kg/ha)
Control
0
22A
0
22A
Nitrogen
(kg/ha) Clipping
Control
No
0
Yes
0
Yes
92B
Yes
92B
Yes
single super phosphate (8.8%P 11%S 19%Ca)
urea (46%N) –split fertiliser applications of 100kg/ha over spring 2003
1
3
DEPARTMENT OF
PRIMARY INDUSTRIES
Feed evaluation of Chilean needle
grass Fertiliser addition & Clipping
• Results since spring 2003…
• Clipped CNG continues to have significantly more ME (2003 &
2004)
• N fertilised - significantly more ME at day 63 & day 398
1
4
DEPARTMENT OF
PRIMARY INDUSTRIES
Feed evaluation of Chilean needle
grass Spraytopping
• Feed value quantified throughout growing season (FeedTest)
– compared to phalaris (Phalaris aquatica)
• Trial conducted at Bannockburn (Hamilton Hwy) Victoria spring
2003
• Treatments
– Two spray times, linked to growth stage
– Two spray rates (Glyphosate)
Treatment
1
2
3
4
5
Glyphosate
Growth stage at application
(g a.i./ha)
No spray
Seedhead development – head at leaf sheath base
128
Seedhead development – head at leaf sheath base
255
Seedhead emergence
128
Seedhead emergence
255
1
5
DEPARTMENT OF
PRIMARY INDUSTRIES
Feed evaluation of Chilean needle
grass Spraytopping
• Effect of spraytopping
– irrespective of time of spray & rate of spray
• Plants that were spraytopped (both CNG & Phalaris)
– significantly higher dry matter percentage (DM%)
– significantly lower fibre content (NDF)
• Application rate (both CNG & Phalaris)
– no significant responses
1
6
DEPARTMENT OF
PRIMARY INDUSTRIES
Feed evaluation of Chilean needle
grass
• Clipped CNG - significantly more ME than unclipped (2003 &
2004)
• N fertilised - significantly more ME than non N at day 63 & day
398
• Spraytopped Plants (both CNG & Phalaris)
– significantly higher dry matter percentage (DM%)
– significantly lower fibre content (NDF)
1
7
DEPARTMENT OF
PRIMARY INDUSTRIES
Effect of Stock Class on Chilean
needle grass seed production
• CNG can be valuable winter feed
when in its vegetative state
• Grazing is a means to reduce seed
production
• Cattle graze CNG better than sheep
1
8
DEPARTMENT OF
PRIMARY INDUSTRIES
Effect of Stock Class on Chilean
needle grass seed production
• Trial established to quantify the amount of standing seed
remaining after grazing by sheep or cattle in different grazing
regimes.
– Animal production
– pasture changes
• Treatments initiated spring 2004 ongoing
– Cattle Vs Sheep
• Angus cows and calves
• Suffolk X ewes and lambs
– Rotational Vs Set stock grazing
• 12DSE/ha equivalent
• 4 paddock time based rotation
1
9
DEPARTMENT OF
PRIMARY INDUSTRIES
• Trial layout
• Greenvale
VIC
• property of
Ian Souter
• Managed by
John & Alan
McKenzie
• Weed CRC
summer
student
Aaron Dodd
• 30ha trial
area
2
0
DEPARTMENT OF
PRIMARY INDUSTRIES
Effect of Stock Class on Chilean
needle grass seed production
• Trial Measurements
– Standing CNG seed
• panicle and stem
• seed set harvest
– Pasture regrowth after grazing
• Growth composition
• BOTANAL
– Pasture composition change
• Basal observations
• Ground cover
– Animal liveweight & condition
score
• Monthly
2
1
DEPARTMENT OF
PRIMARY INDUSTRIES
Results - Seed production
grams of CNG seed/
sq m
Effect of type of grazer on standing CNG
seed
80
74
60
Control (No graze)
40
Sheep
20
0
18
Cattle
4
• Grazing cw. ungrazed
– reduced standing seed
• panicle
• stem cleistogene
• Cattle cw. Sheep
– cattle grazed more than
sheep
• approx 100 seeds/g
2
2
DEPARTMENT OF
PRIMARY INDUSTRIES
Results - Pasture regrowth
• Grazing cw. Ungrazed
– BOTANAL (pasture cages)
– early spring (d56)
– grazing reduced CNG
2
3
DEPARTMENT OF
PRIMARY INDUSTRIES
Results Animal production
• Sheep Vs Cattle
– Liveweight (kg/ha, DSE/ha)
– Welfare
2
4
DEPARTMENT OF
PRIMARY INDUSTRIES
Stockclass conclusions
• Grazing
– significantly reduced CNG seed production (panicle & stem)
– changed early spring regrowth to a more palatable composition
– Cattle significantly more effective than sheep
• Managed grazing with cattle to reduce seed production
2
5
DEPARTMENT OF
PRIMARY INDUSTRIES
Time of Burning - Chilean needle
grass
• Burning can sterilise weed seeds
both on the plant and in the soil
seedbank
• Trial conducted at Greenvale
Victoria (Property of L&J
Karmel).
– Summer 2004/2005 ongoing
2
6
DEPARTMENT OF
PRIMARY INDUSTRIES
Time of Burning - Chilean needle
grass
• Treatments
– 3 burning times
– 20x20m plots
– drip torch strip ignition(leeward side)
Treatment
1
2
3
4
Burn time
Control
Seedfall
Summer
Autumn
Growth stage
Seedfall
Dormant – Post seedfall
Starting Vegetative growth
2
7
DEPARTMENT OF
PRIMARY INDUSTRIES
Time of Burning - Chilean needle
grass
• No effect of time of burn as yet...
• Burning prior to seedfall reduced panicle seeds left standing
• patchy burns
• Burning significantly increased CNG seedlings when compared to
unburnt
• decreased vegetative litter
• increased bare soil
Early summer
Mid Summer
Autumn
2
8
DEPARTMENT OF
PRIMARY INDUSTRIES
Time of Slashing - Chilean needle
grass
• Slashing reduces dry matter during reproductive phases
– reduced panicle seeds (regeneration)
• Vector for the spread of CNG.
• Evaluation of different times of slashing related to CNG growth
stage
• Trial conducted at Greenvale Victoria (Property of L&J Karmel).
– Summer 2004/2005 ongoing
2
9
DEPARTMENT OF
PRIMARY INDUSTRIES
Time of Slashing Chilean needle
grass
• Treatments
– 7 slashing combinations
– 5x20m plots
– 3 point linkage rotary slasher
Treatment Slashing frequency Slash time
growth stage
1
None
Control
2
Single
Oct
Swollen/emerging
3
Single
Nov
Emerged/flowering
4
Single
Dec
Seedfall
5
Double
Oct & Nov
Combinations of above
6
Double
Nov & Dec
Combinations of above
7
Triple
Oct, Nov & Dec Combinations of above
3
0
DEPARTMENT OF
PRIMARY INDUSTRIES
Time of Slashing - Chilean needle
grass
• Time of slashing (from 2004 only)
– no effect on seedlings in following
season
– no effect on botanical composition
• CNG
• Desirable perennials
• litter (Dec Slash)
3
1
DEPARTMENT OF
PRIMARY INDUSTRIES
Pasture competition - species
• Pasture competition can make soil resources unavailable to weed
species
• This trial evaluated the competitiveness of 3 pasture species at
different sowing & fertiliser rates.
• Trial conducted at Wildwood Victoria (autumn 2004), on the
property of Robyn Kissel ‘Grevisfield.’
– non arable infestation of CNG.
3
2
DEPARTMENT OF
PRIMARY INDUSTRIES
Pasture competition - species
• Treatments
– 3 species
• Phalaris aquatica,
• Dactylis glomerata
• Festuca arundinacea
– 2 sowing rates
– 2 fertiliser rates (Di ammonium
Phosphate)
– 45x20m plot area (one grazing cell),
– Sowing using all terrain disc seeder
(RockHoppa by AgReCon)
– Tractor fitted with high flotation tyres
(Trelleborg)
• The trial plots were made up of 30
grazing cells across 15 lanes of a 16
lane grazing system operating on a
90-100day rotation stocked equivalent
to 35DSE/ha (Cattle).
3
3
DEPARTMENT OF
PRIMARY INDUSTRIES
Pasture competition - species
Treatment Pasture Species
1
ControlA
2
Tall FescueB
3
Tall FescueB
4
Tall FescueB
5
CocksfootC
6
CocksfootC
7
CocksfootC
8
PhalarisD
9
PhalarisD
10
PhalarisD
Seed Rate Fertiliser
None
High
yes
Normal
yes
High
None
High
yes
Normal
yes
High
None
High
yes
Normal
yes
High
None
A
Control plots were not fertilised or sown to any pasture
species
B
Jessup MaxP Tall fescue (Festuca & Goulburn Subterranean
clover.
C Kara
Cocksfoot (Dactylis glomerata) & Goulburn
Subterranean clover.
D Holdfast
Phalaris (Phalaris aquatica) & Goulburn
Subterranean clover.
E
Seed rates
Jessup MaxP Tall fescue (Goulburn sub clover)
Normal rate 22kg/ha (6kg/ha)
High rate
44kg/ha (12kg/ha)
Kara Cocksfoot (Goulburn sub clover)
Normal rate 7kg/ha (6kg/ha)
High rate
14kg/ha (12kg/ha)
Holdfast Phalaris (Goulburn sub clover)
Normal rate 8kg/ha (6kg/ha)
High rate
16kg/ha (12kg/ha)
Note: Sub clover seed was lime coated and inoculated. Seed
rate is expressed as equivalent sowing rate of bare seed.
3
4
DEPARTMENT OF
PRIMARY INDUSTRIES
Effect of Soil fertility and pH
• Nassella species may be less responsive to soil
fertility than phalaris species
• Trial established to evaluate the response of
Chilean needle grass to different levels of soil
fertility and pH
• Glasshouse trial - DPI Frankston Winter/spring
2005
– LaTrobe university honours student James
Winters
• Treatments (fully factorial)
– 3 levels of Phosphorus
– 3 levels of Nitrogen
– 3 soil pH levels
3
5
DEPARTMENT OF
PRIMARY INDUSTRIES
Effect of Soil fertility and pH
• Measurements
– seedling vigour (destructive harvest)
– mature plants (still growing!)
• Results - Response to soil Phosphorus
– Seedling height
• Phalaris plants significantly higher than CNG (d19 onwards)
– Shoot weight
• Phalaris plants significantly higher than CNG
– Leaf area
• Phalaris leaf area significantly higher than CNG (78cm2 vs 19cm2)
– Root Length
• Phalaris roots significantly longer than CNG
• CNG root length increased less than Phalaris in response to P
3
6
DEPARTMENT OF
PRIMARY INDUSTRIES
Conclusion
• Feed evaluation of Chilean Needle Grass
• fertiliser and spraytopping had limited effects
• Reducing seed production/seedbank
– Grazing
• significantly reduced CNG seed production (panicle &
stem)
• Cattle significantly more effective than sheep
– Burning
• reduced panicle seeds
• increased seedlings
– Slashing
• decreased panicle seeds
• Competition and Selective manipulation
– Herbicide integration
• Flupropanate & allow pasture regeneration
– CNG slow response to soil Phosphorus
3
7