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Herbicides
Authority
Group 14
Formulation
Product
Company
Active ingredient Formulation
Package size
Authority (PCP# 29012)
Nufarm Agriculture Inc.
Sulfentrazone
Solution: 480 g/L
4
x 3.8 L jug
89
mL/acre = 40 acre/jug.118 mL/acre = 32 acre/jug.
Crops and Staging
Crop
Stage
Rate*
Chickpea
Prior to seeding or up to 3 days post
seeding
89 - 118
mL per acre
Field peas
Flax
Sunflowers
Note: *Rate is dependent on soil type, pH and organic matter; please refer to the label.
Weeds Controlled and Staging
Broadleaf weeds controlled
kochia
lamb’s quarters
red root pigweed
wild buckwheat
Application Information
Authority herbicide may be applied to the soil as a pre-plant or pre-emergence (to weed and crop) surface
application. Do not make fall applications to any crops.
How to Apply
:
Ground only.
Water Volume
:
Minimum 40 L/acre.
Application Tips
All soil applications of Authority herbicide require adequate rainfall for herbicidal activation.
Do not
apply Authority (or any sulfentrazone products) in consecutive years. In case of drought in any of those years,
a subsequent application of Authority should be further delayed.
Do not
apply to soils classified as coarse-textured
soils.
Do not
apply in fine texture soils with less than 1.5% organic matter.
Do not
apply in any type of soils with an
organic matter content greater than 6%.
Do not
use on soils with a pH of 7.8 or greater. If using irrigation with water
that has a pH greater than 7.5, please review the label for adverse crop response. If adequate moisture from rainfall
or irrigation is not received within 7 to 10 days of application, a shallow incorporation no deeper than 5 cm may be
needed to obtain adequate weed control.
Do not
store the sprayer overnight or for an extended period of time with
the sulfentrazone spray mixture in the tank.
How it Works
Sulfentrazone controls weeds by the process of protoporphyrinogen oxidase inhibition (membrane disruption), a
mode-of-action commonly referred to as PPO inhibition. Sulfentrazone is primarily taken up by the roots of treated
plants.
Expected Results
Plants emerging from treated soil turn necrotic and die after exposure to light. Foliar contact causes rapid desiccation
and necrosis of exposed plant tissue. Shoot-root soil placement studies indicate that sulfentrazone is primarily
absorbed by the roots of the plant following soil applications.
Restrictions
Re-cropping restrictions
:
Alfalfa, barley, corn (field corn), wheat (spring and durum): 12 months after application,
winter wheat: 16 months, canola, corn (sweet and pop), sorghum: 24 months, lentils: 36 months.
For crops not listed above, a minimum rotational crop interval of 36 months must be observed and a representative