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Safety - page 25 • First aid - page 33 • Resistance management - page 41
Herbicides
Rate
Varro: 0.2 L/acre
Application Information
How to Apply
:
Apply with ground equipment or by air.
Water volume
:
Ground: minimum of 18.9 L/acre. Air: minimum of 11.3 L/acre.
Application Tips
Do not apply to crop that is under stress due to abnormal environmental conditions such as frost, extreme heat, low
fertility, drought, flooding or disease and/or insect damage as crop injury may result. Under DROUGHT conditions -
Do not spray Varro if time between seeding and spraying exceeds 35 days as (drought hastens crop development). Do
not spray Varro three days prior to or following cold temperatures (3°C or lower) Do not apply to crops underseeded
to legumes. Apply only once per season.
Do not use Varro if another Group 2 grass herbicide has been previously applied in the same season. For best results,
apply to emerged, young, actively growing weeds. Weed control may also be reduced if application is made when
weeds are dust covered or in the presence of heavy dew, fog or mist/rain.
How it Works
Varro: Thiencarbazone-methyl: Uptake is primarily via foliage and is transported to areas on new shoot growth where
it inhibits the enzyme acetolactate synthase (ALS). Inhibition of this enzyme prevents protein production, which
leads to gradual death of target weeds.
Expected Results
Growth of susceptible plants stops rapidly, and after a few days, plants develop chlorotic discolouration on the
leaves, which sometimes turn red. Complete control may take two to four weeks.
Restrictions
Rainfall
:
Rainfall within 60 minutes of application may reduce effectiveness.
Grazing restrictions
:
Do not graze the treated crop or cut for forage within 7 days or cut for hay within 30 days
after application.
Pre-harvest Interval
:
Do not harvest spring or durum wheat for grain or straw within 60 days of application.
Do not harvest winter wheat for grain or straw within 72 days of application.
Re-cropping
:
The following crops can be planted 10 months after application: alfalfa, barley, canary seed, field corn,
canola, chickpeas, dry bean, flax (including low linolenic acid varieties), lentils, mustard, oats, field peas, soybeans,
sunflowers, timothy, wheat (spring, durum and winter).
Environmental Precautions
This product is toxic to aquatic organisms and non-target terrestrial plants. Observe buffer zones of 1 metre with
ground application. Do not allow into surface water, drains and groundwater.
Toxicity
Moderately toxic by ingestion. Acute oral LD
50
(
rats) = > 2,000 mg/kg. Moderate skin and eye irritation.
Storage
Store in a cool, dry place. Do not store below freezing. Shake well before using.
Varro (cont’d)