Herbicides for Spear Thistle Control

These herbicide recommendations are made subject to the product being registered for that purpose under relevant legislation. It is the user's responsibility to check that registration or an off-label permit covers the proposed use. Always read the herbicide label.

If in doubt, visit the Australian Pesticides and Veterinary Medicines Authority (APVMA) website at www.apvma.gov.au.

Only herbicides registered for use in pasture and non-cropping situations are listed in the following table. For recommendations in specific crops consult an agronomist.

Care must be taken in using herbicides as non-target plants contacted may be harmed.

Wetting agents

Carefully consult the product label for specific directions regarding the use of wetting agents or adjuvants.

Waterways and wetlands

Be careful! Many herbicides can cause damage to waterways and wetlands. Check the herbicide label directions carefully before use near waterways and wetlands. For more information see Guidelines for Safe and Effective Herbicide Use Near Waterways.

Herbicide brands

Herbicides are referred to by the active chemical ingredient in the following table. The product trade names in this publication are supplied on the understanding that no preference between equivalent products is intended and that the inclusion of a product does not imply endorsement by DPIPWE over any other equivalent product from another manufacturer. Information on available brands containing the herbicide you require should be obtained from a reputable herbicide supplier or the APVMA website at www.apvma.gov.au.

There may be a number of products with the same active ingredient but with alternate formulations (concentration) registered for control of a weed eg: Glyphosate 360g/L, Glyphosate 450g/L may be registered for use on the same weed. Alternate formulations such as these will have a different application rate. Always check the label.

Boom Spray Application

Stage of Growth
Herbicide
(active
ingredient)
Example of commercial product (concentration of active ingredient)
Application rate of commercial product
Withholding
period
Comments
SeedlingsMCPA sodium salt(250 g/L)2L- 4.5 L/ha
7 days
Apply to mature grasses.

Consult your agronomist for tolerance levels for legumes should any be present.

The use of MCPA is preferred to 2,4-D (amine and ester) in situations where legumes are undersown in the crop.
RosetteMCPA amine(500 g/L)2.2 L/ha
7 days
The use of MCPA is preferred to 2,4-D (amine and ester) in situations where legumes are undersown in the crop.
Agritone® 750
(750 g/L)
1.45 L/ha
7 days
The use of MCPA is preferred to 2,4-D (amine and ester) in situations where legumes are undersown in the crop.
2, 4-D amine Amicide® 625
(625 g/L)
1.4 L/ha
7 days
The use of MCPA is preferred to 2,4-D (amine and ester) in situations where legumes are undersown in the crop.

This product may only be used from 15 April to 15 September unless permitted by the Registrar of Chemical Products, DPIPWE.
Seedling - young rosette2, 4-D ester Estercide® Xtra 680

(680 g/L)
1.15-2.1 L/ha
7 days



Use higher rates as plants mature.

The use of MCPA is preferred to 2,4-D (amine and ester) in situations where legumes are undersown in the crop.

This product may only be used from 15 April to 15 September unless permitted by the Registrar of Chemical Products, DPIPWE.
MCPA + DicambaKamba® M
(340 g/L MCPA+ 80 g/L Dicamba)
2.8 - 4.0 L/ha
7 days
Use higher rate on larger weeds.
Rosette prior to stem elongationClopyralidLontrel® 750 SG
(750 g/L)
20 or 28 g/ha +
1 - 1.5L MCPA amine (500 g/L)
7 days
Use higher rates on multicrowned plants or large rosettes

Spraying may be done any time during active growth, usually early winter to spring.

Clovers and medics will be eliminated for at least 12 months
Actively growingGlyphosate360 g/L


Roundup PowerMAX®
(540 g/L)
2-3 L/ha


1.35-2 L/ha


n/a
Use the lower rates on weeds up 15cm tall, increase to higher rate where weeds are over 15cm tall.

Does not provide residual control.

Non-selective and will damage or kill trees and grasses that come into contact with spray drift.
Roundup® Biactive™
(360 g/L)
2-3 L/haSuitable for use in or near waterways.

Use the lower rates on weeds up 15cm tall, increase to higher rate where weeds are over 15cm tall.

Non-selective and will damage or kill trees and grasses that come into contact with spray drift.
Sulfometurn methylOust®
(750 g/kg)
200-400 g/ha
n/a
For use in industrial/commercial areas, rights of ways and around agricultural buildings.

Use higher rate for dense infestations or where weeds are greater than 15 cm diameter.
Use the higher rate for longer term residual control.

May be mixed with glyphosate.

Spot Spraying

Stage of Growth
Herbicide
(active
ingredient)
Example of commercial product (concentration of active ingredient)
Application rate of commercial product
Withholding
period
Comments
Seedling - young rosetteMCPA Sodium salt(250 g/L)350 mL/15L water
7 days
Use the lower rate for seedlings, the higher rate for medium sized rosettes.

Can damage vegetable and horticultural crops, avoid spray or vapour drift reaching crops such as grape vines, tomatoes, vegetables, poppies or flower crops.
SeedlingMCPA amine(500 g/L)22 mL/10L water
7 days
The use of MCPA is preferred to 2,4-D (amine and ester) in situations where legumes are undersown in the crop.
RosetteAgritone® 750
(750 g/L)
14.5 mL/10L water
7 days
2, 4-D amine Amicide® 625
(625 g/L)
14 mL/10L water
7 days
The use of MCPA is preferred to 2,4-D (amine and ester) in situations where legumes are undersown in the crop.

This product may only be used from 15 April to 15 September unless permitted by the Registrar of Chemical Products, DPIPWE.
Seedling - rosette2, 4-D esterEstercide®
Xtra 680
(680 g/L)
11.5 mL -
21 mL/10L water
7 days



Use higher rates as plants mature.

The use of MCPA is preferred to 2,4-D (amine and ester) in situations where legumes are undersown in the crop.

This product may only be used from 15 April to 15 September unless permitted by the Registrar of Chemical Products, DPIPWE.
MCPA + DicambaKamba® M
(340 g/L MCPA+ 80 g/L Dicamba)
60 mL/15L water
7 days
Spray seedlings/young rosette stage.
Rosette prior to stem elongationClopyralidLontrel®
(750 g/L)
10 g/10L water
7 days
Spraying may be done any time during active growth, usually early winter to spring.

Clovers and medics will be eliminated for at least 12 months.
Actively growingGlyphosate360 g/L



Roundup
Power MAX®
(540 g/L)
75-100 mL/15L water


50-70 mL/15L water
n/a
Use the lower rates on weeds up 15cm tall, increase to higher rate where weeds are over 15cm tall.

Does not provide residual control.

Non-selective and will damage or kill trees and grasses that come into contact with spray drift.
Roundup®
Biactive™
(360 g/L)
75-100 mL/15L waterSuitable for use near waterways.

Use the lower rates on weeds up 15cm tall, increase to higher rate where weeds are over 15cm tall.

Non-selective and will damage or kill trees and grasses that come into contact with spray drift.
Sulfometurn methylOust®
(750 g/kg)
6-12 g/15L water
n/a
For use in industrial/commercial areas, rights of ways and around agricultural buildings.

Use higher rate for dense infestations or where weeds are greater than 15 cm diameter.

Use the higher rate for longer term residual control.
May be mixed with glyphosate.

Important Disclaimer
To the extent permitted by law, the Tasmanian Department of Primary Industries, Parks, Water and Environment (including its employees and consultants) excludes all liability to any person for any consequences, including but not limited to all losses, damages, costs, expenses and any other compensation, arising directly or indirectly from using information or material (in part or in whole) contained on this website.