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Safety - page 25 • First aid - page 33 • Resistance management - page 41
Herbicides
Leaching
:
Simazine is a chemical that can travel (seep or leach) through soil. Use appropriate buffer zones near water
bodies or when there is a shallow water table.
Toxicity
Acute oral toxicity: Practically non-toxic. Oral LD
50
(
rats) = > 5,000 mg/kg. May be irritating to eyes and cause
dermatitis.
Storage
Store in dry area; heating not required.
Prism
Group 2
Formulation
Product
Company
Active ingredient
Formulation
Continer size
Prism ((PCP# 23983)
E.I. duPont Canada
Rimsulfuron: 25%
Dry flowable
480
g
One 480 gram package treats 20 acres.
Crops and Timing
Crop
Timing
Remarks
Potatoes (irrigated)
Apply prior to initiation of flowering
Delay cultivation for 7 - 10 days after application.
Note:
Because potato varieties differ in their tolerance to herbicides, limit first use of Prism herbicide to a small area of each variety prior to adoption as a
field practice.
Weeds and Staging
Apply to young, actively growing broadleaf weeds before the canopy closes.
Annual grasses
Perennial grasses
Broadleaf
Barnyard grass
1 - 6
leaf stage,
maximum 2 tillers
Quackgrass
3 - 6
leaf stage
(
< 25 cm tall, leaf
extended)
Lamb’s-quarters
(
suppression)
4 - 6
leaf stage
(
< 10 cm tall or
across)
Fall panicum
Green foxtail
Redroot pigweed
Witchgrass
Yellow foxtail
Rate
Prism: 24 grams/acre plus non-ionic surfactant (Citowett Plus, Ag Surf or Agral 90): 0.25% v/v or 0.2 L/100 L of
spray solution.
Application Information
With: Apply with ground equipment. Do not apply by air.
Water volume
: 40
L/acre.
Application Tips
A rapid fluctuation in temperature (greater than 20 ºC difference within 24-36 hours) will stress the crop. For
maximum crop safety, allow 48-72 hours for the crop to acclimatize before spraying Prism. For maximum crop safety,
apply only when the temperature in the 24 hours before and after the application ranges between 5 ºC and
28
ºC. Crop injury may result if application is made to potatoes that have been stressed. If potatoes have been injured
by frost, wait 48-72 hours before applying Prism herbicide.
Princep Nine-T/Simazine 480 (cont’d)