Carfentrazone plus metribuzin


3 ACTIVE INGREDIENTS: Carfentrazone 375g/kg + metribuzin 90g/kg


Water dispersible granule

4 CHEMICAL GROUP:G and C. Herbicide.

G - Aryl triazolinone sub group. Inhibitor of protoporphyrinogen oxidase
C - Triazinone group. Inhibits the protoporphyrinogen oxidase enzyme of photosynthesis at photosystem II.


Group C herbicidesAmetryn 500Ametryn 500g/L
Atrazine 500 FlowableAtrazine 500-600g/L
Atrazine 900 GranulesAtrazine 900g/kg
Atrazine plus SimazineAtrazine 250g/L + simazine 250g/L
BasagranBentazone 480g/L
BetanalPhenmedipham 157g/L
Bromacil 800Bromacil 800g/kg
BromoxynilBromoxynil 200g/L
ChloridazonChloridazon 650g/kg
Cyanazine 900Cyanazine 900g/kg
DiuronDiuron 500g/L
DiuronDiuron 900g/kg
Forest MixAtrazine 620g/kg + hexazinone 210 g/kg
Forest Mix GranulesAtrazine 150g/kg + hexazinone 50 g/kg
Gesagard 500 SCPrometryn 500g/L
GraslanTebuthiuron 200g/kg (or400g/kg or600g/kg)
IoxynilIoxynil 250g/L
Linuron 500Linuron 500g/L or 500g/kg (or800g/kg)
Metribuzin 750Metribuzin 750g/kg
Metribuzin plus SimazineMetribuzin + simazine
Metribuzin plus TribunilMetribuzin 140g/kg + Methabenzthiazuron 560g/kg
Prometryn 900Prometryn 900g/kg
PropanilPropanil 360 g/L (600g/L)
Sencor 480Metribuzin 480g/L
Simazine Flowable 500Simazine 500g/L
Simazine Granules 900Simazine 900g/kg
Terbacil 800Terbacil 800g/kg
TerbuthylazineTerbuthylazine 750 g/kg (or800-875g/kg)
Terbutryn 500Terbutryn 500g/L (or 750g/kg)
TribunilMethabenzthiazuron 700g/kg
VelparHexazinone 750g/kg (or 250g/L)

Group G herbicidesBlazerAcifluorfen 224g/L
ButafenacilButafenacil 100g/L
Carfentrazone 240Carfentrazone-ethyl 240g/L
Carfentrazone 400Carfentrazone-ethyl 400g/kg
FlumioxazinFlumioxazin 500g/kg
OxyfluorfenOxyfluorfen 240g/L (or 500g/L)
Saflufenacil 700Saflufenacil 700g/kg


A contact and residual fast acting, translocated, early post emergence herbicide for the control of broad-leaved weeds in cereals.

For further information see individual components Carfentrazone 400 and Metribuzin 750


Good coverage is essential for maximum contact action.
Best results on moist soil, in fine weather on actively growing weeds with less than 8 leaves.
Use higher rate of herbicide and water on older and/or denser weed infestations.
Don't use wetters or oils as increased crop damage may occur


Rainfast in 6 hours.
Frost effects: Reduced weed control under frosty conditions
Wind: 3-20 km/hour recommended on label.
Inversions: Avoid application during low level inversions as excessive drift may occur.
Temperature: Best results in warm weather.
Delta T and relative humidity: Avoid application when Delta T is greater than


Use of adjuvants such as wetting agents or spray oils may result in crop damage.
Spray Oils: Use may result in crop damage.


Hard water: There may be a slight loss of activity due to ionic bonding in very hard water.
Colloids: Some loss of activity as the amount of clay in the water increases. If it is difficult to see a coin on the bottom of a 10 litre bucket full of water then the water should be cleared or an alternate source found.
pH: Keep the pH between 5 and 8. Highly alkaline water may cause loss of efficacy.
Tank life: 10% loss over 1-2 days depending on amount of light entering tank.


Trace elements.
Don't mix with grass selective herbicides.


Boom sprays:

Carrier volume: 50-150 L/ha. Use higher volumes on heavy weed infestations and on very small weeds.
Nozzles: Flat fan 11001 to 11002. Avoid using 11003 single orifice or 11006 twin orifice or larger nozzles as reduced weed control may result from insufficient droplet density. Similarly avoid flood jet, low-drift, boomless jet or CDA applicators. Teejet TT nozzles are not recommended as poor control has resulted.
The label recommends using coarse spray droplets with air induction nozzles to reduce drift. Floodjet, boomless jets, misters and CDA applicators are not recommended on the label
Pressure: 150-400 kPa.

Aerial application:

Not registered for application by aircraft.


Clean Up:
Clean soon after spraying to reduce the risk of forming dried deposits that may be difficult to remove.
Remove filters and clean separately. Rinse with soapy water (eg 500 mL or g of Drive, Dynamo, Omo or Surf per 100 L water) or water plus 0.25% wetting agent and run through boom. Rinse with water.
Remove filters and clean separately. Rinse with water then fill with soapy water (eg 500 mL or g of Drive, Dynamo, Omo or Surf per 100 L water) or water plus 0.25% wetting agent and run through boom. Leave it stand for a few hours or overnight. Rinse with water.
Or use the same procedure with a commercial spray tank and equipment cleaner.


None reported.


AllNone on label. Metribuzin has some residual but rates are low for this product.


AllHarvestNot required
AllGrazing14 days


12 hours unless impervious footwear and chemical resistant gloves are used.


Use elbow length protective gloves, face shield or goggles when handling the concentrate.

19 SOIL:

Little effect of Soil Texture, pH and organic matter has little effect on carfentrazone.
Soil moisture: Best results when soil is moist. May cause crop leaf spotting when soil is waterlogged.


Uptake and translocation:

This is a contact herbicide that is rapidly absorbed through leaves within a few hours of application.
Less than 0.001 ppm of carfentrazone moved to the grain when applied at 35 g a.i./ha to wheat at the late tillering stage. 0.07-0.1 ppm of carfentrazone and its metabolites were present in straw and leaves 60 days after application. Similar results were recorded in Maize.

Physiological effects:

Carfentrazone disrupts membranes by inhibition of protoporphyrinogen oxidase which is involved in chlorophyll production. This results in yellowing of the plant and the stopping of photosynthesis leading to death.
The herbicide requires light and oxygen for action and works better at higher temperatures.
The carfentrazone is modified within susceptible plants to phytotoxic compounds.
Metribuzin inhibits photosynthesis at photosystem II.

Residual Life and Breakdown:


Controls broad-leaved weeds in grass crops. Some grasses can be affected.

Crop tolerance:

Crop symptoms may include spotting Drift may show as yellow spotting. New growth may have yellowing.

Varietal sensitivities:

Effect on Clover Species:

Kills clovers.

Effect on Medic Species:

Kills medics.

Effect on Lucerne:

Kills seedling lucerne. Damages established lucerne.

Effect on Native Plants:

Causes leaf spotting on most broad-leaved native plants.




Tissue death occurs within a few hours to days of spraying. Symptoms develop more rapidly under warm, moist conditions. Under very dry conditions symptoms may be slower to develop. Symptoms are usually chlorosis (yellowing) progressing into necrosis (death).


Transient leaf spotting may occur on cereal crops and recovery usually occurs within 2-3 weeks.
Drift may show as yellow spotting. New growth may have yellowing or no symptoms.





Poison schedule: S6.
Mammalian toxicity - Low.
Acute oral LD50 - Low, >2000 mg/kg (rats), [For comparison table salt is 3000 mg/kg]
Acute dermal LD50 - Low, >2000 mg/kg (rat).
Skin - Slightly irritating. Non sensitising.
Eye - Slightly irritating.
Vapour inhalation - Harmful. LC50 - >2.8 mg/L air (rat, 4 hours).
Chronic oral toxicity NOEL - ppm for two years.
Not mutagenic or teratogenic (i.e. does not cause cancer or reproductive problems).

Other Species -

Birds - Carfentrazone - Slightly toxic. LD50 > 2250 mg/kg. Metribuzin has moderate toxicity to birds. The LD50 in bobwhite quail = 164 mg/kg and mallard duck = 460-680 mg/kg.
Fish - Carfentrazone - moderately toxic. LC50 1.6-2 ppm. Metribuzin is very toxic to fish and other aquatic organisms. The 96-hour LC50 in rainbow trout = 74.6 mg/L and golden orfe = 141.6 mg/L,
Invertebrates - Carfentrazone - slightly toxic. LC50 >9.8 ppm. Metribuzin - low toxicity. Daphnia 48-hour LC50 = 49.6 mg/L.
Bees - Carfentrazone - Low toxicity.
Algae - Carfentrazone - Highly toxic. EC50 = 15 ppb. Metribuzin - highly toxic to algae EC50 green algae = 0.021 mg/L.
Earthworms - Carfentrazone - Low toxicity. NOEL > 820 mg/kg soil.


The breakdown pathway in animals is similar to that in plants. The main breakdown is by hydrolysis, oxidation and dechlorination. Very little parent carfentrazone is left after 48 hours in plant and animal systems.
At 3 mg/kg feed daily intake for cows no residues were detected in milk, or meat. At 10 mg/kg feed daily some residues were detected in milk and kidney. At 90 mg/kg in goats residues were detected in milk, kidney and liver. There was no accumulation. The maximum transfer factor (maximum residue versus feeding rate) was 0.08% for milk and 0.13% for kidney.
About 87% of ingested carfentrazone is excreted within 24 hours with about 80% in the urine and 7% in the faeces.
Poultry fed 10 mg/kg daily intake had less than 0.007 ppm in eggs, fat and meat. 0.06 ppm was detected in liver.
In rats, 72-87% of ingested carfentrazone is passed in the urine and 10-26% passed in faeces within 7 days of consumption with most being eliminated within 24 hours. Peak plasma levels of carfentrazone and its metabolites occur at 4- 6 hours and red blood cell levels at 8-16 hours. It is rapidly absorbed and excreted.
There is little or no potential for bio accumulation.


Wheat: At 30 g a.i./ha of carfentrazone applied post emergence to Wheat, residues were detected at 1 hour and up to 7 days after application. No residues have been detected at 14 days after application or in the grain or straw.
Barley, Oats and Triticale: At 24 g a.i./ha of carfentrazone applied post emergence to Barley, Oats or Triticale, residues were detected at 1 hour and up to 7 days after application. No residues have been detected at 14 days after application or in the grain or straw.


Overexposure to carfentrazone-ethyl shown by laboratory animals include decreased activity, tearing eyes, bleeding from the nose and incoordination.


Contact a doctor or Poisons Information Centre on 13 11 26.
If Swallowed - Do NOT induce vomiting. Give a glass of water Contact a doctor.
If on Skin - Wash skin thoroughly with soap and water.
If in Eyes - Flush with water for 15 minutes.
If Inhaled - Remove patient from contaminated area to fresh air.
Advice to doctor - Treat symptomatically. Metribuzin and Carfentrazone-ethyl have generally low acute toxicity. Treatment is controlled removal of exposure followed by symptomatic and supportive care.


Carfentrazone ethyl has a half life in soil of 1-5 days and its metabolites have a half life of 3-26 days in moist soil at normal temperatures. In field applications with 100 g a.i./ha applied, no detectable residues of the parent or its metabolites were found below 20 cm. In Rice paddies the half life in water of carfentrazone ethyl and its metabolites was 2-10 days and in the sediment 23-59 days. It is degraded in both aerobic and anaerobic conditions.
Aerobic soil metabolism: In a silty clay loam, it has an initial rapid breakdown over the first 8 days with a half life of 2.2-2.5 days followed by a slower breakdown rate with a half life of 43-71 days. In other soils at water contents of 50-75% of field capacity and temperatures of 10-25 degrees C the time for 50% degradation ranged from <0.1 days to 2.5 days and the time for 90% degradation varied from 0.2 days to 482 days. The acid metabolites have half lives ranging from 30-3000 days.
Anaerobic soil metabolism: Carfentrazone ethyl half life of less than 1 day and 90% degradation within 4 days.
Aerobic aquatic metabolism: Carfentrazone ethyl half life ranged from 0.84 days at 20 C to 5 days at 10 C with little difference between totally wet soils and those with surface water only.
It has a half life in water exposed to sunlight of 8.5 days.
Hydrolysis: It rapidly hydrolyses at pH 9 with a half life of 5.1 hours at 20 or 25 C. At pH 7 the half life is 13.7 days at 20 C and 8.6 days at 25 C. It is hydrolytically stable at pH 5.
Photo-degradation in water: Carfentrazone ethyl and it major metabolite rapidly photo-degrade in light. The half life is 69.7 hours at pH5 (where minimal hydrolysis occurs) This is equivalent to 8.3 days of sunlight at 40 degrees south in summer. It is stable in the dark.
It has a soil mobility that is low.
Photo-degradation in soil: Carfentrazone ethyl was not broken down by sunlight on soil.
Ground water contamination: It has a low potential for movement is soils. Under field use conditions carfentrazone ethyl and its acid metabolites remained in the top 20 cm of soil even though they have the potential to be mobile.
Bio-accumulation: Low potential for accumulation, Log P =3.36, bio-concentration factor in fish = 206.
Does not accumulate in milk and tissues.
Replanting intervals - short. No crop rotation restrictions.

Metribuzin is of moderate persistence in the soil environment. The half-life of Metribuzin varies according to soil type and climatic conditions. Soil half-lives of 30 to 120 days have been reported; a representative value may be approximately 60 days. Metribuzin is poorly bound to most soils and soluble in water, giving it a potential for leaching in many soil types. Soil mobility is affected by many site-specific variables, including the amount of soil organic matter, particle size distribution, porosity, rainfall, and application rates. Metribuzin has been detected in some rivers, wells and groundwater in the USA. The major mechanism by which Metribuzin is lost from soil is microbial degradation. Losses due to volatilization or photo-degradation are not significant under field conditions.
Breakdown in water: The half-life of Metribuzin in pond water is approximately 7 days. If present, Metribuzin would most likely be found in the water column rather than the sediment, due to its low binding affinity and high water solubility. Breakdown in vegetation: Metribuzin is absorbed through the leaves when plants are given surface treatment, but the primary route for uptake is through the root system. From the roots, it is translocated upward, becoming concentrated in the roots, stems, and leaves of treated plants. In non-susceptible plants it is de-aminised to more water-soluble conjugates; in susceptible plants it is not metabolized and disrupts photosynthesis in the chloroplast.


See HerbiGuide Species Solution tab.


See HerbiGuide Species Solution tab.


UN number: 3077
CAS numbers: Carfentrazone 128639-02-1. Metribuzin 21087-64-9.
OPP Chemical Code:
Hazchem code:
NOHSC classification:
Safe Work Australia classification: Hazardous
Land transport:
Dangerous goods class (ADG): not classified as a dangerous good.
Sea transport:
Proper shipping name: ENVIRONMENTALLY HAZARDOUS SUBSTANCE, SOLID, N.O.S. (Contains Carfentrazone).
International Maritime Dangerous Goods Code (IMDG): Marine pollutant.
Class: 9 (Miscellaneous Dangerous Goods)
Packaging group: III
Air transport (IATA)
UN 3077,
Proper shipping name: ENVIRONMENTALLY HAZARDOUS SUBSTANCE, SOLID, N.O.S. (Contains Carfentrazone).
International Maritime Dangerous Goods Code (IMDG): Marine pollutant.
Class: 9 (Miscellaneous Dangerous Goods)
Packaging group: III
Hazchem code 2Z.
Hazard Identification Number (HIN) 90.

Risk phrases:
R20 Harmful by inhalation.
Safety phrases:
S2 Keep out of reach of children.
S22 Do not breathe dust.
S24/25 Avoid contact with skin and eyes.
S37/39 Wear Suitable gloves and eye/face protection.
Mandatory No-Spray Zones
Aquatic environment - 5 metres downwind
Terrestrial environment - 20 metres downwind
Records of use are required to be kept for 2 years.


Colour: Light brown solid granules.
Odour: Sweet musty like odour
Form: Granules.
Chemical name:
Empirical formula:
Water solubility at 25 C. - Disperses in water.
Oil solubility - .
Octanol:Water ratio at 25 C. - at pH 5;
Vapour Pressure: Non volatile. 1.2 x 10-7 mm Hg at 25 C. -
Dissociation constant - pKa
Boiling point - .
Melting point - .
pH 5-7.
Molecular weight -
Density - Carfentrazone -1.423 g/cm3 at 25 C. Specific gravity 1.075 g/cm3 at 20 C.
Half life in water - Carfentrazone - 8.5 days at pH5 and 35 C. At 25 C, >30 days at pH 5, 8.6 days at pH 7, 0.148 days at pH 9. At 20 C, >30 days at pH 5, 13.7 days at pH 7, 0.212 days at pH 9.
Thermal stability: Stable from -17 C to 150 C.
Flammability: Not flammable. Thermal decomposition and burning may produce toxic by products. May produce carbon monoxide, oxides of nitrogen, hydrogen chloride and hydrogen fluoride.
Corrosive properties: Non corrosive to stainless steel and polyethylene used in sprayers.


Vacuum or shovel spill into containers. Avoid breathing dust. Wash with soap, water and acetic acid/vinegar. Then wash the area with a bleach or caustic soda ash solution. Finally, wash with a strong soap and water solution.
Ventilate area after cleanup.

33 FIRE:

Extinguish with water spray, foam, carbon dioxide or dry agent.
Toxic fumes may be released in fire. Wear breathing apparatus or avoid smoke.



Ashton, F.M. and Crafts, A.S. (1981) Mode of Action of Herbicides. (Wiley-Interscience publication).
Kearney, P.C. and Kaufman, D.D. (1976). Herbicides. Chemistry, degradation and mode of action. Vol 1 & 2.
FMC Label and MSDS 2015


Collated by HerbiGuide. For more information see or phone 08 98444064.