S
pray Drift Management
The interaction of many equipment and weather-related
factors determines the potential for spray drift. The
applicator is responsible for considering all these factors
when making application decisions.
A
VOIDING SPRAY DRIFT IS THE RESPONSIBILITY
OF THE APPLICATOR.
•
Importance of Droplet Size
The most effective way to reduce drift potential is to apply
large droplets (>150 - 200 microns). The best drift
management strategy is to apply the largest droplets that
provide sufficient coverage and control. The presence of
sensitive species nearby, the environmental conditions, and
pest pressure may affect how an applicator balances drift
control and coverage. APPLYING LARGER DROPLETS
REDUCES DRIFT POTENTIAL, BUT WILL NOT
PREVENT DRIFT IF APPLICATIONS ARE MADE
IMPROPERLY OR UNDER UNFAVORABLE
ENVIRONMENTAL CONDITIONS! See
Wind,
Temperature and Humidity, and Temperature
Inversions sections of this label.
• Controlling Droplet Size - General Techniques
- Volume - Use high flow rate nozzles to apply the
highest practical spray volume. Nozzles with higher
rated flows produce larger droplets.
- Pressure - Use the lower spray pressures recommended
for the nozzle. Higher pressure reduces droplet size
and does not improve canopy penetration. WHEN
HIGHER FLOW RATES ARE NEEDED, USE A
HIGHER-CAPACITY NOZZLE INSTEAD OF
INCREASING PRESSURE.
-
Nozzle Type - Use a nozzle type that is designed for the
intended application. With most nozzle types, narrower
spray angles produce larger droplets. Consider using
low-drift nozzles.
• Controlling Droplet Size - Aircraft
- Number of Nozzles - Use the minimum number of
nozzles with the highest f
lo
w r
a
te tha
t provide uniform
coverage.
- Nozzle Orientation - Orienting nozzles so that the
spray is emitted backwards, parallel to the airstream
will produce larger droplets than other orientations.
- Nozzle Type - Solid stream nozzles (such as disc and
core with swirl plate removed) oriented straight back
produce larger droplets than other nozzle types.
-
Boom Length - The boom length should not exceed 3/4
of the wing or rotor length - longer booms increase drift
potential.
- Application Height - Application more than 10 ft
above the canopy increases the potential for spray drift.
• Boom Height (Ground)
Setting the boom at the lowest labeled height (if specified)
which provides uniform coverage reduces the exposure of
droplets to evaporation and wind. For ground equipment,
the boom should remain level with the crop and have
minimal bounce
.
• Wind
D
rift potential increases at wind speeds of less than 3 mph
(due to inversion potential) or more than 10 mph.
However, many factors, including droplet size and
equipment type determine drift potential at any given
wind speed. AVOID GUSTY OR WINDLESS
CONDITIONS.
Note: Local terrain can influence wind patterns. Every
applicator should be familiar with local wind patterns and
how they affect spray drift.
• Temperature and Humidity
When making applications in hot and dry conditions, set
up equipment to produce larger droplets to reduce effects
of evaporation.
• Temperature Inversions
Drift potential is high during a temperature inversion.
Surface inversions restrict vertical air mixing, which
causes small suspended droplets to remain close to the
ground and move laterally in a concentrated cloud.
Surface inversions are characterized by increasing
temperature with altitude and are common on nights with
limited cloud cover and light to no wind. They begin to
form as the sun sets and often continue into the morning.
Their presence can be indicated by ground fog; however,
if fog is not present, inversions can also be identified by
the mo
vement of smoke from a ground source or an
aircraft smoke generator. Smoke that layers and moves
laterally in a concentrated cloud (under low wind
conditions) indicates an inversion, while smoke that
moves upward and rapidly dissipates indicates good
vertical air mixing.
• Shielded Sprayers
Shielding the boom or individual nozzles can reduce the
effects of wind. However, it is the responsibility of the
applicator to verify that the shields are preventing drift
and not interfering with uniform deposition of the
product.
GENERAL RESTRICTIONS
AND LIMIT
ATIONS
• Maximum Seasonal Use Rate: Do not apply more than a total
of 48 f
luid ounces (3 pints) of DuP
ont™ MEPEX® GIN
OUT™ (0.132 pounds mepiquat chloride) per acre per season.
•
The sum of all products and formulations containing mepiquat
chloride must not exceed 0.132 pounds of mepiquat chloride
per acre per season. This maximum equals 48 fluid ounces (3
pints) of MEPEX® GIN OUT™ (0.35 pounds mepiquat
chloride per gallon).
•
Pr
ehar
v
est Interval (PHI): Do not apply within 30 days of
harvest.
•
Restricted Entr
y Inter
v
al (REI):
12 hours.
• Do not plant another crop within 75 days of last treatment.
• Stress: Do not apply to cotton plants under severe stress due to
adverse weather conditions, mite, insect, or nematode
dama
g
e
,
disease, herbicide injury, or fertility stress. If using
the low-rate multiple option, discontinue use until the stress is
alleviated. Do not apply a single application of 8 to 16 fluid
ounces of MEPEX
®
GIN OUT™ to cotton that is stressed
due to lack of soil moisture.
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