Herbicides
235
• 
Safety - page 25 • First aid - page 33 • Resistance management - page 41
Crops, Rates and Timing
Crop
Rate per acre
Timing
Princep Nine T Simazine 480
Alfalfa (1 year or older)
0.45
kg
Not registered
Apply in the fall after last cutting but prior to permanently
frozen ground conditions. One application per season.
Bird’s-foot trefoil
0.45
kg
Not registered
For stands at least one year old, apply from September to
November before permanently frozen ground conditions. Apply
in year of seeding if population is at least 5 plants per 10 cm
2
and if plants are at least 15 cm high.
Corn
0.6 - 1.0
kg
1.4 - 3.4
L
Apply one week prior to seeding; incorporate to a depth of 2.5
cm. Use low rate on sandy soils, and the high rate on loams
and clays.
Raspberries
0.8 - 1.0
kg
Apply in early spring but not on young shoots.
Shelterbelts consisting
of caragana, green ash,
Siberian elm, American elm,
and boxelder maple
2.0 - 2.8
kg
3.8 - 5.7
L
Apply in the fall or early spring, pre-emergent to weeds. Injury
may occur to trees grown in saline soils.
Weeds and Staging
Apply prior to emergence of weeds in spring.
barnyard grass
crabgrass
lamb’s-quarters*
lady’s-thumb
perennial species starting
from seed
purslane
ragweed*
smartweed
volunteer clovers
wild buckwheat
wild oats
yellow foxtail
*
Some biotypes of these weeds may not be controlled by these products
Application Information
With
:
Apply with ground equipment only.
Water volume
: 120
L/acre. Shelterbelts: 200 L/acre.
Application Tips
Gentle agitation required during mixing and spraying. After any break in the spray application, agitate thoroughly.
Do not overlap application. Alfalfa, bird’s-foot trefoil: Do not apply to same field for more than 3 consecutive years.
Do not apply Gramoxone within 1 year after the Princep application.
How it Works
Acts through the roots of germinating weeds and inhibits photosynthesis, preventing emergence.
Expected Results
Weed-free ground.
Restrictions
Rainfall
:
Princep Nine-T requires rainfall to be activated, negligible effect on Simazine.
Grazing
:
Allow 30 days between application and grazing to dairy and beef cattle and sheep, and 60 days between
application and cutting for hay.
Re-cropping
:
Re-cropping: Only corn may be planted during the season of application. If rates greater than
0.8
kg/acre are used, only corn may be planted the following year. Injury may occur to succeeding crops of white
beans, onions, peas, tomatoes and turnips if dry weather occurs during the year of application. Sugar beets should not
be planted the year following Princep Nine-T application.
Environmental Precautions
The active ingredient, simazine, is non-toxic to birds, insects (bees), and aquatic invertebrates and slightly toxic to
fish. Avoid the potential of well or surface water contamination. Do not use this product within 10 metres of the water
sources.
Princep Nine-T/Simazine 480 (cont’d)