Logran B-Power

1 Trade nameManufacturerForm



3 ACTIVE INGREDIENTS: Butafenacil 200g/kg plus Triasulfuron 500g/kg.


Water dispersible granule.


Inhibitor of protoporphyrinogen oxidase and acetolactate synthase inhibitor.



Chlorsulfuron (Glean), metsulfuron (Ally), oxyfluorfen (Goal), sulfometuron (Oust), triasulfuron (Logran).


An agricultural herbicide for knockdown and residual control of a broad spectrum of grass and broad leaf weeds. It is normally applied before planting.

As a post emergence application it is relatively non selective due to the butafenacil component which breaks down soon after application, allowing Wheat to be planted one day after application.

Butafenacil is a non selective, non residual, poorly translocated herbicide that is absorbed through the leaves.

Triasulfuron is a selective, residual, translocated herbicide that is absorbed through the roots and leaves.

Its main uses are for the control of a large variety of grass and broad-leaved weeds when they are very young or before they emerge and is usually applied before planting Wheat. It is of low toxicity to mammals, birds and fish. Triasulfuron acts on the ALS enzyme in plants which is not present in animals and this is the main reason for its low toxicity. Butafenacil inhibits protoporphyrinogen oxidase. The product presents little hazard to the environment because it is used at low rates and degrades relatively quickly in most field situations. Plants resistant to triasulfuron have developed and are expected after repeated use.


Apply in fine weather at least one day before planting.

Triasulfuron is usually mixed with 30-100 l water per hectare and broadcast through hydraulic nozzles. It can be applied in ultra low volumes of carrier.

Surfactants and spray oils usually improve weed control.

Acidifiers may increase triasulfuron absorption, especially on waxy plants.

Young, actively growing weeds are most sensitive and crops most tolerant of triasulfuron. Under cold, wet or stressful conditions the weeds become more tolerant and the crop less tolerant of sulfonylurea herbicides.

Rain within a few hours of application may reduce the effectiveness of post-emergence applications. Leaching rains reduce the effectiveness of pre-emergence applications.


Non ionic surfactants and spraying oils increase the absorption and herbicidal activity.

Triasulfuron is antagonistic with diclofop and other grass herbicides. The antagonism is variable and appears to depend on the ratio of the herbicides.

Triasulfuron applied pre emergence reduces the effectiveness of most post emergent wild oat herbicides. Puma S appears to be the least affected. Achieve loses 6-8% of its wild oat control.

Triasulfuron forms stable metal and ammonium salts so it is incompatible with most trace elements and ammonium sulphate. Hard or salty water may reduce its effectiveness.


Plant populations tolerant to triasulfuron are expected to occur naturally after repeated use. Tolerant crops can be developed.

To reduce the risk of resistance, don't use more than one group B product per season or more than 2 group B products every 4 seasons.


Most of the triasulfuron applied to leaves is absorbed. Small amounts move out of the leaf to other shoots and even less to the roots. Most is translocated in the phloem. Absorption by roots from the soil solution is not as efficient but this is compensated for by better movement up to the leaves. Within the plant, triasulfuron stops cell division very quickly by its action on the ALS enzyme. Secondary effects on photosynthesis, respiration and ethylene production produce the symptoms of yellowing and reddening of grasses and leaf drop in broad-leaved weeds.

Species tolerant to triasulfuron such as the cereals degrade it more quickly than do sensitive plants. Degradation products are non toxic and herbicidally inactive. Herbicide resistance appears to be due to plants with a less sensitive ALS enzyme or plants with a greater ability to break down the herbicide. The growth of seedlings may be stimulated at low dose rates.

It does not normally affect seed germination.


Crop tolerance:

Varietal sensitivities:

Wheat - Amery, Brookton, Calingiri and Kulin are sensitive to pre em applications and post em applications up to the 2 tiller stage.

Effect on Clover Species:

Effect on Medic Species:

Effect on Lucerne:

Effect on Native Plants:


Growth stops soon after application. Plants wilt within a few hours of application due to the butafenacil component.

Plants emerging after application may grow to a leaf or two then will start to yellow or redden. In broad-leaved weeds this may be an intervenal yellowing. Annual weeds are usually dead within 4 weeks of spraying. Under cold and wet conditions they may remain alive as severely stunted plants with few roots and die from water stress in spring. Butafenacil/triasulfuron has little effect on germination and weeds may emerge and grow for a week or two before dying.


Triasulfuron does not affect the microbes associated with N fixation in legumes.

Triasulfuron and residues in the soil from previous applications may make the crop more susceptible to Take-All, CCN, Rhizoctonia and zinc, copper and manganese deficiency (Hollaway, 1997).

It has no impact on N or P nutrition of cereals (Wilhelm et al, 1995).



Mammalian toxicity - low.

Acute oral LD50 - Triasulfuron >4000 mg/kg. Product > 5000 mg/kg.

Acute dermal LD50 - Triasulfuron >3000 mg/kg (rabbit). Product > 2000 mg/kg.

Skin - Triasulfuron not irritating, not sensitising. Butafenacil not irritating, not sensitising.

Eye - Triasulfuron mildly irritating. Product slight irritant.

Vapour inhalation - LC50 - Triasulfuron >5 mg/L air (rat).

Chronic oral toxicity NOEL - Triasulfuron 100 ppm for two years.

Not carcinogenic, mutagenic or teratogenic (i.e. does not cause cancer or reproductive problems).

Birds - low toxicity.

Fish - low toxicity LC50 >200 ppm.

Invertebrates - low toxicity.

Bees - low toxicity.

Highly toxic to algae and some aquatic plants.


Triasulfuron does not usually evoke any symptoms in animals.

The main enzyme (ALS) that is attacked in plants does not occur in animals.

Butafenacil inhibits haeme synthesis in animals. Liver necrosis and liver weight increases and porphyria have been observed in animal studies.

No cases of human poisoning have been recorded.

Symptoms non specific.


Triasulfuron has a half life in soil of about 2 weeks -2 months. Its half life is much longer in soils with high pH (up to 9 months). At a soil pH of less than 7 it is broken down by hydrolysis and microbial degradation. At a pH of more than 8 there is little hydrolysis and only microbial breakdown. Breakdown is most rapid in warm, moist, acid and light textured soils with high organic matter. Little is naturally degraded due to exposure to sunlight and volatilisation. Triasulfuron has an EPA classification for soil mobility that ranges from intermediate mobility to very mobile depending on the soil type. Mobility usually increases with increasing soil pH and decreasing organic matter. It will move up, down and sideways in the soil profile depending on the water flow. However, it is not expected to cause ground water contamination problems due to its relatively rapid degradation in plants and soils, low use rates and low toxicity.

Some crops should not be planted for many months after triasulfuron application. This is because they are sensitive to extremely low levels of triasulfuron and not because of high levels of persistence of the herbicide in the soil.

Triasulfuron does not accumulate in the milk or tissues of animals. Most is excreted intact in the urine of monogastric animals or as a conjugate in ruminants.

Replanting Intervals:

Some crops should not be planted for many months after triasulfuron application. This is because they are sensitive to extremely low levels of triasulfuron and not because of high levels of persistence of the herbicide in the soil. Lentils, Medic, sugar beet and onions are very sensitive to triasulfuron. Canola, Setaria Millet, Lucerne, sunflower, potatoes, mustard corn and flax are sensitive. Peas, Beans, Mung Beans, Pearl Millet, Ryegrass, Sorghum, Cotton, Soybeans, Safflower, Bluegrass and Guar are moderately sensitive and Wheat, Triticale, Rye, Barley, Oats and Black Nightshade are tolerant.

On Wimmera grey clays triasulfuron at 30 g Logran/ha reduced the growth of canola, medic and lentils 12 months after application and the growth of lentils 2 years after application (Hollaway, 1997).

See label for further information.


Vapour Pressure at 25 C. - Triasulfuron Very low.

Dissociation constant - Triasulfuron weak acid.

Solubility - Triasulfuron 1500 mg/L in water.

It has a leaching index of 25-30 for Triasulfuron. (for comparison, trifluralin is 0-1 and chlorsulfuron is 25-30).

Triasulfuron has a half life 30 days at 20 degrees and 50% WHC in Mohlin soil.

Logran B-Bower

2.Concentration of Active Constituent : Butafenacil 200g/kg plus Triasulfuron 500g/kg.
3.Formulation : Water Dispersible Granule
4.Poison Schedule : Exempt from scheduling.
5.Trade name : Logran B-Power - Syngenta
6.Product Colour : Grey to beige granules.
7.Product Flammability : Non-flammable. Non flashing. Non combustible. Non explosive.
8.Dangerous Goods Class : Not classed as a dangerous good for transport.
9.Shelf Life : In excess of 2 years.
10.Mixtures Compatibility : Avadex BW (tri-allate) Roundup CT (glyphosate) Spray.Seed (paraquat + diquat)
11.Registered Crop(s) : Wheat.
12.Effect of Soil Texture on Herbicide : Application should not be made to ridged or excessively cloddy soil. Crop damage can occur on light soils.
13.Effect of Soil pH on Herbicide: Varies carryover life for triasulfuron. At 20oC and pH4.5 half life is 15 - 30 days.
14.Effect of Soil Organic Matter on Herbicide : Not critical on application rate.
15.Mode of Action : Leaf and root absorption for triasulfuron. Leaf absorption for butafenacil.
16.Application Timing : Apply prior to planting.
17.Rate Variations : 50 g/ha.
18.Rates Selection : Lower rate on sandy clay loams with pH greater than 8.5. Higher rate 35 g/ha for Annual Ryegrass, Paradoxa Grass, Soursob, Doublegee, Capeweed, Wireweed, and Wild Radish.
19.Crop Damage (Crop Tolerance) : Excellent tolerance demonstrated in trials on more than 70 wheat varieties.
20.Effect on Crop : Slight retardation on early crop growth may be observed when crops are planted in sandy soils with pH > 8.5.
21.Effect on Legume Species : Do NOT apply to crops undersown with legumes.
22.Soil Moisture at Application :
DRY - Less activity on the weeds.

MOIST - Ideal conditions.

WATERLOGGED - Damage may occur in light soils after heavy rain.
23.Frost Effects : Not applicable.
24.Frost Free Days Required After Application : Not applicable.
25.Effect of Application Water Quality on Herbicide :
Saline Water - Reduced activity.

Soil Colloids - Not critical.

In acid water and in warm weather, Logran can breakdown at rates of up to 10% a day.
26.Recommended Water Volume : 30 - 100 L/ha boom.
27.Nozzle Type : Flat fan or hollow cone.
28.Recommended Nozzle Pressure : Follow manufacturer's recommendations.
29.Recommended Filter Size :
30.Recommended Wetter : Non ionic surfactant.
31.Other Additives : Uptake is not compatible with Logran. Add Avadex BW where wild oats are anticipated as a problem.
32.Rain Fastness : 4 hours.
33.Time Interval Before Effect is Noticed : 2-14 days depending on growing conditions, warm and moist conditions favour the activity.
34.Weed Symptoms : Wilting of emerged plants. Plants germinating after spraying show increasing chlorosis and anthocyanin (purpling) leading to necrosis or death.
35.Effect of Herbicide/Disease Interaction on Crop : Some crop yellowing may occur where Rhizoctonia, Take-all and cereal cyst nematode are already present.
36.Withholding Period : 49 days.
37.Plant-Back Period : Wheat - 1 day. Durum Wheat - is one day but longer times are preferred as some varieties are sensitive. Barley, Oats, Triticale, and Cereal Rye - following season. For other crops could be up to 24 months depending on soil pH.
38.Spray Tank Clean-Up : Residues of triasulfuron may cause damage to crops other than wheat if these crops are sprayed with contaminated equipment.
Physically remove deposits. Clean with 300 mL household bleach solution (4% chlorine) per 100 L water. Fill tank and agitate for 15 minutes. Run solution through spray lines for at least one minute. Dispose of rinsing and repeat the procedure. Remove nozzle, screens and filters and clean them separately. Rinse sprayer with clean water.
39.Other Comments : Apply before sowing to a moist seed bed without clods or ridges. Incorporation by sowing improves the reliability of the weed control results, use narrow low profile 10 cm combine points to ensure even mixing of soil. Poor incorporation will result in uneven weed control or 'striping' of weeds. High temperature and moisture increase the rate of degradation. Rainfall following application, preferably within 7 - 10 days, is needed to 'activate' Logran and move it into the weed root zone.
Density 0.5 g/mL

Non corrosive.

Non oxidising.


Syngenta (2003) Logran B-Power Label 53545/0302 and MSDS.

Hollaway, K. (1997). Australian Grain. April-May 1997, 11-14.

Wilhelm, N., Ramsey, W and Neate, S. (1995) Australian Grain. Western Focus. October-November. vii.


Collated by HerbiGuide. For more information see www.herbiguide.com.au or phone 08 98444064.