Home LEADProductsManufacturingNewsContact

Simazine 900 WG


APVMA Code :58437

Active Constituent(s): 900g/kg simazine
Registered For:


 Commercial use

 Domestic use

Overview: For the control of weeds in chick peas, lupins, T-T canola, orchards, vineyards and certain other horticultural crops and non-crop situations.

Chemical Group triazine


 SDS (297.7 KB)

 Label (1 MB)

General Instructions


Ospray Simazine 900 WG Herbicide is a pre-emergent herbicide, which is most effective when applied to bare, moist soil. Because it acts mainly through the roots of weeds, best results are obtained when rain or irrigation water move the herbicide down to the root zone within 2 weeks of application. The duration and effectiveness of control depends on the amount applied, the type of soil, intensity of leaching and species of weeds present.


Integrated Weed Management Strategy For TT-Canola

An Integrated Weed Management Strategy for TT Canola (the strategy) has been developed and funded by the Canola Association of Australia and certain companies. The strategy outlines recommendations, measures and options for weed management., including management of herbicide resistance in weed populations. The Strategy is available from an Ospray Representative and the Canola Association of Australia. A programme has been developed that outlines sound agronomic practices and integrated weed management programmes designed to optimise the performance of TT Canola. It is advised that consultation on IWM be undertaken with an accredited agronomist prior to use of Ospray Simazine 900 WG Herbicide on TT Canola.



  • Avoid dry sowing in heavily weed-infested paddocks. Wait for a weed germination after the opening rains in weedy paddocks. Use a pre-plant knockdown or cultivation. No weeds should be allowed to survive at this stage.
  • Adapt the weed control program to the anticipated weed spectrum and pressure: Broadleaf Weeds and Ryegrass: Use Simazine 900 WG or Atrazine 900 WG plus trifluralin pre-emergence. A follow-up with a Group A herbicide (if ryegrass is susceptible) or atrazine 900 g/kg may be necessary.
  • Broadleaf Weeds only: Use Atrazine 900 WG post-emergence.
  • DO NOT use Atrazine 900 WG or Simazine 900 WG if the area to be treated had a triazine herbicide applied to it last season.
  • Watch for escapes, especially in paddocks with a long history of Group C Herbicide use.
  • DO NOT use Group C Herbicides in consecutive years.



On acid soils (pH less than 6.5) - The maximum rate of Atrazine 900 WG or Simazine 900 WG or a combination of the two products to be applied to the crop during the growing season is 2 kg ai/ha.


On alkaline soils (pH greater than 6.5) - the maximum rate of Atrazine WG or Simazine 900 WG or a combination of the two products to be applied to the crop during the growing season is 1kg ai/ha.


Post-emergence use - it is recommended that Atrazine 900 WG only be used, and at rates of 1kg ai/ha or less, on both acid or alkaline soils.


Resistance Weed Reporting

Growers should collect plant or seed samples where weeds that are normally susceptible to atrazine and simazine may be resistant, get them tested and seek professional advice.




Half fill the spray tank with clean water. Commence vigorous agitation. Add granules steadily. DO NOT dump. Ensure complete dispersion before filling to volume with water. Continue agitation during spraying. DO NOT leave spray solution in tank overnight.




Use a boom sprayer or knapsack for small areas. 50-200L of mixture per hectare should be applied with the boom and a minimum equivalent to 500L per hectare through the knapsack sprayer. Clean spray equipment immediately after use using several flushes of water with detergent.



DO NOT apply to TT-canola by aircraft. Apply only with a low boom sprayer with a 60m buffer zone downwind of treated fields to natural or impounded lakes or dams, and a 20m buffer zone for any well, sink hole, intermittent or perennial stream. Apply only to areas where run-off is unlikely to occur or where run-off may be captured by farm earthworks.



This product may be mixed with amitrole, atrazine, diuron, glyphosate, diquat, paraquat and paraquat-diquat mixes. Because the products may vary from time to time, a small-scale compatibility test should be carried out before mixing in the spray tank. For residual control of annual weeds in non-crop areas, pome and citrus orchards and vineyards only, mixtures of this product and glyphosate may be used. Half fill the spray tank with clean water before adding this product at the recommended rate and mix thoroughly. Then add 360g/L glyphosate product at 3L/ha or 700mL/100L and the remaining water. Maintain adequate agitation and use the mixture promptly. Do not use lower rates of glyphosate (360g/L) where control of perennial weeds is desired.


Soil Moisture

If sufficient rain to thoroughly wet the weed root zone has not fallen within 14 days of application, water in with the equivalent of 13 mm of rain. If applied under dry conditions and irrigation is not available, mechanical incorporation to a depth of not more than 4cm within 7 days of sowing may assist results.


Resistance Warning


Ospray Simazine 900 WG Herbicide is a member of the triazine group of herbicides. Ospray Simazine 900 WG Herbicide has the inhibitor of photosynthesis mode of action. For weed resistance management Ospray Simazine 900 WG Herbicide is a Group C herbicide. Some naturally occurring weed biotypes resistant to Ospray Simazine 900 WG Herbicide and other Group C herbicides may exist through normal genetic variability in any weed population. The resistant individuals can eventually dominate the weed population if these herbicides are used repeatedly. These resistant weeds will not be controlled by Ospray Simazine 900 WG Herbicide or other Group C herbicides. However, resistance should not be assumed without first viewing the method of application, the coverage and the timing of application. Resistance to Ospray Simazine 900 WG Herbicide cannot be predicted and may occur at any time. It is not due to a fault with the product and Ospray Pty Ltd accepts no liability for any losses that may result from the failure of Ospray Simazine 900 WG Herbicide to control resistant weeds.


Protection of wildlife, fish, crustaceans and environment

DO NOT contaminate streams, rivers or waterways with the chemical or used containers. DO NOT use container for any other purpose. This product is very highly toxic to algae and aquatic macrophytes.


Protection of crop, native and other non-target plants

DO NOT spray foliage of desired plants, except lupins (WA only).


DO NOT use under Peach, Apricot, Plum trees, ornamental Prunus or near newly planted shrubs.


DO NOT plant crops other than those recommended on this label for at least nine (9) months following treatments at rates up to 2.5 kg/ha. At higher rates, plantings may not be possible for very long periods afterwards.


DO NOT use on sandy or porous soils near desirable plants or trees, or where roots of such may extend, or are near the surface. Crops such as red beet, lettuce, cabbage, tomato, cucumber and carrots are particularly sensitive to simazine residues.


DO NOT exceed highest rate recommended for any particular crop.


DO NOT use on white or grey sands (WA only).


DO NOT use in channels or drains where the roots of desirable plants may extend.


DO NOT apply under weather conditions, or from spraying equipment, that may cause spray to drift onto nearby susceptible plants/crops, cropping lands or pastures. Araucaria, Corymbia, Eucalyptus and Pinus plantations: Field trial and use experience has indicated that the following species are tolerant. Test tolerance before treating other species.

Araucaria - all commercial species

Corymbia - maculata

Eucalyptus - agglomerate, calophylla, camaldulensis, cladocalyx, cloeziana, dunnii, globulus, grandis, laevopinea, nitens, pilularis, pseudoglobulus, regnans, rudis, saligna, wandoo.

Pinus - Caribaea and hybrids, elliotti, pinaster, radiata.


Safety Directions


Avoid contact with eyes and skin. DO NOT inhale dust or spray mist. Wash hands after use.




Store in the closed, original container in a dry, cool, well-ventilated area out of direct sunlight.



Shake empty bag into spray tank. Do not dispose of undiluted chemicals on site. Puncture or shred and bury empty containers in a local authority landfill. If no landfill is available, bury the containers below 500 mm in a disposal pit specifically marked and set up for this purpose clear of waterways, desirable vegetation and tree roots. Empty containers and product should not be burnt.


Precautions Re-entry Period

DO NOT enter treated area without protective clothing until spray has dried.


Product details last updated on 02 Jul 2010


DISCLAIMER: This is not the SIMAZINE 900WG HERBICIDE label. To view or print the label for this product, click the "MSDS/Label" tab at the top of this page. Always follow label instructions.


For specialist advice in an EMERGENCY only phone 1800 033 111, TOLL-FREE, ALL-HOURS, NATIONWIDE

To the topTo the top
Alphabetical index  Ι  Sitemap  Ι  Disclaimer  Ι  Sales terms and conditions  Ι  Useful links