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Sencor® is a proven broad-spectrum herbicide registered for broadleaf and grassy weed control in potatoes and a wide range of other crops.

Active ingredient:

Metribuzin (Group 5)


  • Sencor® 75 DF - Water Dispersible Granular (75% dry flowable)
  • Sencor® 480 F – Suspension (480 g/L)


  • Sencor® 75 DF is available in 2.5 kg jugs
  • Sencor 480 F is available in 5 L jugs


  • Each 2.5 kg jug treats 6.7 to 17.9 ha (16.5 to 44 ac.)


  • Each 2.5 kg jug treats 1.7 to 4.5 ha (4 to 11 ac.)
  • Each 5 L jug treats 2.2 to 5.9 ha (5.5 to 14.5 ac.)


6 hours after application

Pre-Harvest Interval:

60 days

Features and Benefits

  • Broad-spectrum broadleaf and grass weed control
  • Provides early weed control during critical crop stages
  • Can be applied pre-emergent or post-emergent
  • Excellent crop safety
  • Rate flexibility (depending on stage, formulation and tank mix partner)


  • Barnyard grass
  • Cheat grass
  • Crab grass
  • Fall panicum
  • Foxtail- green, yellow and giant
  • Johnson grass (seedling)
  • Witch grass


  • Carpetweed1
  • Cockleblur
  • Common chickweed
  • Common ragweed
  • Dandelion (seedling)
  • Green smartweed
  • Jimsonweed1
  • Lady's-thumb
  • Lamb's-quarter
  • Prickly mallow1
  • Prostrate pigweed
  • Redroot pigweed
  • Russian thistle
  • Shepherd's purse
  • Stinkweed
  • Velvetleaf
  • Wild buckwheat2
  • Wild Mustard
  • Wild potato vine
  • Yellow woodsorrel1

For full product details including, pre-emergent or post emergent rates for your region and controlled weeds please reference the Sencor label.

Application Tips and Best Management Practices for Potatoes

Pre-emerge Considerations

  • Must be used with irrigation in Prairie Provinces.
  • Allow hill to settle prior to application as any soil disturbance after application can result in weed escapes.
  • Dry/drought conditions can result in reduced weed control.
  • Needs to be activated before broadleaf weeds reach 4 leaf stage and grasses reach 2 leaf stage.
  • Sencor binds to clay, therefore, higher rates are required in heavier soils for longer residual weed control.
  • Sencor binds to OM. Higher rates are required in higher OM soils, >4%. This also impacts the longer persistence of carryover when considering sensitive subsequent crops. Sencor breaks down faster in soils with higher pH. Low pH soils are at a higher risk for persistence.
  • Do not tank-mix Sencor with 2,4-D.

Post Emergent Considerations

  • Detoxification of Sencor is more concentrated in sunlight.
  • For best weed control and crop safety it is best to spray mid-day in full sunlight with sunny conditions prior to and the day after application.
  • Use high water volumes; 18-20 gallons of water/acre is recommended.
  • Higher water volumes can be used as long as you don’t experience run off.
  • Tank-mixing with rimsulfuron will antagonize rimsulfuron grassy weed control.
  • Under dry and sunny conditions rainfast is 6 hours. Under cloudy conditions allow for 12 hours for rain fastness.
  • Temporary yellowing or leaf burn may occur if crop is under stress from poor growing conditions such as periods of cool, wet, and cloudy weather. Avoid post-emergence application under these conditions.

Crop Tolerance

  • Some potato varieties can be sensitive to Sencor applied post-emergence.
  • Symptoms may appear such as yellowing/necrosis of leaf veins or leaf margins, stunting, and possible delay in harvest.
  • Varietal tolerance can vary and is affected by rate and conditions at application.
  • Apply Sencor in a small test area to ensure risk or level of potential injury is acceptable to the grower prior to adoption as a general field practice. Sensitivity to or injury after a post-emergent application of Sencor is typically visible in the test area within 5 days after application.

Crop Rotation Considerations:

  • Rotation crops such as onions, celery, peppers, cole crops, lettuce, spinach, sugar beets, table beets, turnips, pumpkin, squash, cucumbers, melons, tobacco and non-triazine tolerant canola (rapeseed) are sensitive to Sencor herbicide and may be injured if planted in soil treated with Sencor during the year of application or the following crop year.
  • Fall seeded or cover crops such as wheat, oats, and rye may be injured when seeded within the same season as the application of Sencor.