crop-chem-docs/corpus/epa_ppls/100-1307.md

# ORION HERBICIDE

- EPA Reg No: **100-1307**
- Registrant: SYNGENTA CROP PROTECTION, LLC
- Signal word: Caution
- Active ingredients: MCPA, 2-ethylhexyl ester (42.25%); Florasulam (0.39%)
- Label accepted: 2025-11-04
- Source PDF: https://www3.epa.gov/pesticides/chem_search/ppls/000100-01307-20251104.pdf

---
November 4th, 2025 
 
Rachel Hardie 
Regulatory Product Manager 
Syngenta Crop Protection, LLC 
P.O. Box 18300 
Greensboro, NC 27419 
 
Subject: Label Amendment - Registration Review Mitigation for MCPA & Florasulam (Nine 
Acetolactate Synthase (ALS) Inhibiting Herbicides)
 
 Product Name: ORION HERBICIDE 
 EPA Registration Number: 100-1307 
Case Number: 477893 
Application Dates: February 12, 2020 & October 19, 2023 
 
Dear Rachel Hardie: 
 
The Agency, in accordance with the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), 
as amended, has completed reviewing all the information submitted with your application to 
support the Registration Review of the above referenced product in connection with the MCPA 
& Florasulam (Nine Acetolactate Synthase (ALS) Inhibiting Herbicides) Interim Decisions, and 
has concluded that your submission is acceptable. The label referred to above, submitted in 
connection with registration under FIFRA, as amended, is acceptable. 
 
Should you wish to add/retain a reference to the company’s website on your label, then please 
be aware that the website becomes labeling under the Federal Insecticide, Fungicide, and 
Rodenticide Act and is subject to review by the Agency. If the website is false or misleading, the 
product would be misbranded and unlawful to sell or distribute under FIFRA section 12(a)(1)(E). 
40 CFR 156.10(a)(5) list examples of statements EPA may consider false or misleading. In 
addition, regardless of whether a website is referenced on your product’s label, claims made on 
the website may not substantially differ from those claims approved through the registration 
process. Therefore, should the Agency find or if it is brought to our attention that a website 
contains false or misleading statements or claims substantially differing from the EPA approved 
registration, the website will be referred to the EPA’s Office of Enforcement and Compliance 
Assurance. 
 
A stamped copy of your labeling is enclosed for your records. This labeling supersedes 
all previously accepted labeling and must be used at your next label printing. You must

Page 2 of 2 
EPA Reg. No. 100-1307 
Case No. 477893 
 
submit one copy of the final printed labeling before you release the product for 
shipment with the new labeling. In accordance with 40 CFR 152.130(c), you may 
distribute or sell this product under the previously approved labeling for 12 months 
from the date of this letter. After 12 months, you may only distribute or sell this 
product if it bears this new revised labeling or subsequently approved labeling. “To 
distribute or sell” is defined under FIFRA section 2(gg) and its implementing regulation 
at 40 CFR 152.3. 
 
If you have any questions about this letter, please contact Caleb Carr by phone at 202-566-
0636, or via email at carr.caleb@epa.gov. 
 
 Sincerely, 
 
 
 
 
Maryam K. Muhammad-Perch, Team Lead 
Risk Management and Implementation Branch 4 
Pesticide Re-Evaluation Division 
Office of Pesticide Programs 
 
 
 
 
ENCLOSURE: Stamped label

Orion Herbicide 
Page 1 
FLORASULAM GROUP 2 HERBICIDE 
MCPA GROUP 4 HERBICIDE 
Orion® Herbicide 
For postemergent control of annual broadleaf weeds in wheat (including durum), barley, 
oats, rye and triticale. 
Active Ingredient: 
Florasulam: N-(2,6-difluorophenyl)-8-fluoro-5-methoxy(1,2,4) 
triazolo(1,5-c)pyrimidine-2-sulfonamide .................................................................. 0.39% 
MCPA: 2-methyl-4-chlorophenoxyacetic acid, 2-ethylhexyl ester ......................... 42.25% 
Other Ingredients: 57.36% 
Total: 100.00% 
Orion is formulated as a suspo-emulsion containing 0.033 lb of florasulam and 2.34 lb of 
MCPA expressed as acid equivalent per gallon. 
KEEP OUT OF REACH OF CHILDREN 
CAUTION 
See additional precautionary statements and directions for use on label. 
EPA Reg. No. 100-1307 
EPA Est. No. 
___________ 
Net Contents 
11/04/2025
100-1307

Orion Herbicide 
Page 2 
 
 
FIRST AID 
If swallowed • Call a poison control center or doctor immediately for treatment 
advice. 
• Have person sip a glass of water if able to swallow. 
• Do not induce vomiting unless told to do so by a poison control 
center or doctor. 
• Do not give anything by mouth to an unconscious person. 
If on skin or 
clothing 
• Take off contaminated clothing. 
• Rinse skin immediately with plenty of water for 15-20 minutes. 
• Call a poison control center or doctor for treatment advice. 
If in eyes • Hold eye open and rinse slowly and gently with water for 15-20 
minutes. 
• Remove contact lenses, if present, after the first 5 minutes, then 
continue rinsing eye. 
• Call a poison control center or doctor for treatment advice. 
Have the product container or label with you when calling a poison control center or 
doctor, or going for treatment. 
HOTLINE NUMBER 
For 24-Hour Medical Emergency Assistance (Human or Animal) or 
Chemical Emergency Assistance (Spill, Leak, Fire, or Accident), 
Call 
1-800-888-8372 
 
PRECAUTIONARY STATEMENTS 
 
Hazards to Humans and Domestic Animals 
 
Harmful if swallowed. Prolonged or frequently repeated skin contact may cause allergic 
reactions in some individuals. Wash thoroughly with soap and water after handling and 
before eating, drinking, chewing gum, using tobacco, or using the toilet. 
 
Personal Protective Equipment (PPE) 
 
 
Mixers, loaders, applicators, flaggers and other handlers must wear: 
 
• Long-sleeved shirt and long pants 
• Waterproof gloves 
• Shoes plus socks

Orion Herbicide 
Page 3 
 
User Safety Requirements 
 
Follow manufacturer's instructions for cleaning/maintaining PPE. If no such instructions 
for washables exist, use detergent and hot water. Keep and wash PPE separately from 
other laundry. 
 
Engineering Controls 
 
Pilots must use an enclosed cockpit that meets the requirements listed in the WPS for 
agricultural pesticides (40 CFR 170.240(d)(6)). 
 
Handlers must use closed mixing loading systems during mixing and loading liquids for 
aerial applications to barley, oats, rye, triticale, and wheat. 
 
User Safety Recommendations 
 
Users should: 
 
• Wash hands before eating, drinking, chewing gum, using tobacco or using the toilet. 
• Remove clothing/PPE immediately if pesticide gets inside. Then wash thoroughly 
and put on clean clothing. 
• Remove PPE immediately after handling this product. Wash the outside of gloves 
before removing. As soon as possible, wash thoroughly and change into clean 
clothin
g. 
 
Environmental Hazards 
 
This pesticide is toxic to fish, aquatic invertebrates and aquatic plants. Do not apply 
directly to water, or to areas where surface water is present or to intertidal areas below 
the mean high water mark. Do not contaminate water when disposing of equipment 
washwater or rinsate. Drift and runoff may be hazardous to aquatic organisms in water 
adjacent to treated areas. Runoff of this product will be reduced by avoiding 
applications when rainfall is forecasted to occur within 48 hours. 
 
This chemical has properties and characteristics associated with chemicals detected in 
groundwater. The use of this chemical in areas where soils are permeable, particularly 
where the water table is shallow, may result in groundwater contamination. 
 
NON-TARGET ORGANISM ADVISORY: This product is toxic to plants and may 
adversely impact the forage and habitat of non-target organisms, including pollinators, 
in areas adjacent to the treated site. Protect the forage and habitat of non-target 
organisms by following label directions intended to minimize spray drift. 
 
GROUNDWATER ADVISORY: This chemical has properties and characteristics 
associated with chemicals detected in groundwater. MCPA is known to leach into 
groundwater under certain conditions as a result of label use. This chemical may leach

Orion Herbicide 
Page 4 
 
into groundwater if used in areas where soils are permeable, particularly where the 
water table is shallow. 
 
SURFACE WATER ADVISORY: This product may impact surface water quality due to 
runoff of rain water. This is especially true for poorly draining soils and soils with shallow 
ground water. This product is classified as having high potential for reaching surface 
water via runoff for several months or more after application. A level, well-maintained 
vegetative buffer strip between areas to which this product is applied and surface water 
features such as ponds, streams, and springs will reduce the potential loading of 
florasulam and MCPA from runoff water and sediment. Runoff of this product will be 
reduced by avoiding applications when rainfall or irrigation is expected to occur within 
48 hours. 
 
Shake Well Before Use - Avoid Freezing.

Orion Herbicide 
Page 5 
 
 
CONDITIONS OF SALE AND LIMITATION OF WARRANTY AND LIABILITY 
 
NOTICE: Read the entire Directions for Use and Conditions of Sale and Limitation of 
Warranty and Liability before buying or using this product. If the terms are not 
acceptable, return the product at once, unopened, and the purchase price will be 
refunded. 
 
The Directions for Use of this product must be followed carefully. It is impossible to 
eliminate all risks inherently associated with the use of this product. Crop injury, 
ineffectiveness or other unintended consequences may result because of such factors 
as manner of use or application, weather or crop conditions, presence of other materials 
or other influencing factors in the use of the product, which are beyond the control of 
SYNGENTA CROP PROTECTION, LLC or Seller. To the extent permitted by 
applicable law, Buyer and User agree to hold SYNGENTA and Seller harmless for any 
claims relating to such factors. 
 
SYNGENTA warrants that this product conforms to the chemical description on the label 
and is reasonably fit for the purposes stated in the Directions for Use, subject to the 
inherent risks referred to above, when used in accordance with directions under normal 
use conditions. To the extent permitted by applicable law: (1) this warranty does not 
extend to the use of the product contrary to label instructions or under conditions not 
reasonably foreseeable to or beyond the control of Seller or SYNGENTA, and (2) Buyer 
and User assume the risk of any such use. To the extent permitted by applicable law, 
SYNGENTA MAKES NO WARRANTIES OF MERCHANTABILITY OR OF FITNESS 
FOR A PARTICULAR PURPOSE NOR ANY OTHER EXPRESS OR IMPLIED 
WARRANTY EXCEPT AS WARRANTED BY THIS LABEL. 
 
To the extent permitted by applicable law, in no event shall SYNGENTA be liable for 
any incidental, consequential or special damages resulting from the use or handling of 
this product. TO THE EXTENT PERMITTED BY APPLICABLE LAW, THE 
EXCLUSIVE REMEDY OF THE USER OR BUYER, AND THE EXCLUSIVE LIABILITY 
OF SYNGENTA AND SELLER FOR ANY AND ALL CLAIMS, LOSSES, INJURIES 
OR DAMAGES (INCLUDING CLAIMS BASED ON BREACH OF WARRANTY, 
CONTRACT, NEGLIGENCE, TORT, STRICT LIABILITY OR OTHERWISE) 
RESULTING FROM THE USE OR HANDLING OF THIS PRODUCT, SHALL BE THE 
RETURN OF THE PURCHASE PRICE OF THE PRODUCT OR, AT THE ELECTION 
OF SYNGENTA OR SELLER, THE REPLACEMENT OF THE PRODUCT. 
 
SYNGENTA and Seller offer this product, and Buyer and User accept it, subject to the 
foregoing Conditions of Sale and Limitation of Warranty and Liability, which may not be 
modified except by written agreement signed by a duly authorized representative of 
SYNGENTA.

Orion Herbicide 
Page 6 
 
 
DIRECTIONS FOR USE 
 
It is a violation of federal law to use this product in a manner inconsistent with its 
labeling. 
 
Read all Directions for Use carefully before applying. 
 
Do not apply this product in a way that will contact workers or other persons, either 
directly or through drift. Only protected handlers may be in the area during application. 
For any requirements specific to your state or tribe, consult the agency responsible for 
pesticide regulation. 
 
 
AGRICULTURAL USE REQUIREMENTS 
 
Use this product only in accordance with its labeling and with the Worker Protection 
Standard, 40 CFR Part 170. This standard contains requirements for the protection of 
agricultural workers on farms, forests, nurseries, and greenhouses, and handlers of 
agricultural pesticides. It contains requirements for training, decontamination, 
notification, and emergency assistance. It also contains specific instructions and 
exceptions pertaining to the statements on the label about personal protective 
equipment, restricted-entry interval, and notification to workers (as applicable). The 
requirements in this box apply to uses of this product that are covered by the Worker 
Protection Standard. 
 
Do not enter or allow worker entry into treated areas during the restricted entry 
interval (REI) of 12 hours. 
 
For early entry into treated areas that is permitted under the Worker Protection 
Standard and that involves contact with anything that has been treated, such as plants, 
soil, or water, wear: 
 
• Coveralls 
• Waterproof gloves 
• Shoes plus socks 
 
 
FAILURE TO FOLLOW THE DIRECTIONS FOR USE AND PRECAUTIONS ON THIS 
LABEL MAY RESULT IN CROP INJURY AND/OR POOR WEED CONTROL. 
 
PRODUCT INFORMATION 
 
Use Orion Herbicide as a postemergence herbicide for the control of annual broadleaf 
weeds such as chickweed, wild buckwheat, mustards and cleavers (catchweed

Orion Herbicide 
Page 7 
 
bedstraw) in wheat (including spring, winter and durum), barley, oats, rye and triticale 
not underseeded with legumes. 
 
Orion Herbicide rapidly stops growth of susceptible weeds. However, typical symptoms 
(discoloration) of dying weeds may not be noticeable for 1 to 2 weeks after application, 
depending upon growing conditions and weed susceptibility. Degree of control and 
duration of effect are dependent upon weed sensitivity, weed size, crop competition, 
growing conditions at and following treatment, and spray coverage. 
 
Use Precautions 
 
When applying this product in tank-mix combination, follow all applicable use directions, 
precautions, and limitations on each manufacturer’s label. 
 
Chemigation: Do not apply this product through any type of irrigation system. 
 
Do not apply Orion Herbicide directly to, or otherwise permit it to come into direct 
contact with, susceptible crops or desirable plants including alfalfa, edible beans, 
canola, flowers and ornamentals, lentils, lettuce, peas, potatoes, radishes, soybeans, 
sugar beets, sunflowers, tomatoes, or tobacco. Do not permit spray mists containing 
Orion Herbicide to drift onto such plants. 
 
This product has potential to leach. Do not apply excessive irrigation. 
 
Do not apply to crops underseeded with legumes. 
 
Weed Resistant Management 
FLORASULAM GROUP 
2 HERBICIDE 
MCPA GROUP 4 HERBICIDE 
 
Orion Herbicide contains the active ingredients florasulam which inhibits acetolactate 
synthase (ALS, Site of Action Group 2) and MCPA which causes abnormal cell growth 
(synthetic auxin, Site of Action Group 4). Some naturally-occurring weed populations 
have been identified as resistant to Group 2 and 4 herbicides. Selection of resistant 
biotypes, through repeated use of these herbicides or lower than labeled use rates in 
the same field, may result in weed control failures. A resistant biotype may be present 
where poor performance cannot be attributed to adverse environmental conditions or 
improper application methods. If resistance is suspected, contact your local Syngenta 
representative and/or agricultural advisor for assistance. 
 
Scout and know your field 
• Know weed species present in the field to be treated through scouting and field 
history. An understanding of weed biology is useful in designing a resistance 
management strategy. Ensure the weed management program will control all 
weeds present.

Orion Herbicide 
Page 8 
 
• Fields should be scouted prior to application to determine species present and 
growth stage. Always apply this herbicide at the full labeled rate and correct 
timing for the weeds present in the field. 
Utilize non-herbicidal practices to add diversity 
• Use diversified management tactics such as cover crops, mechanical weed 
control, harvest weed seed control, and crop rotation as appropriate. 
Use good agronomic practices, start clean and stay clean 
• Use good agronomic practices that enhance crop competitiveness. 
• Plant into weed-free fields utilizing tillage or an effective burndown herbicide for 
control of emerged weeds. 
• Sanitize farm equipment to avoid spreading seed or vegetative propagules prior 
to leaving fields. 
Difficult to control weeds 
• Fields with difficult to control weeds should be planted in rotation with crops that 
allow the use of herbicides with an alternative mode of action or different 
management practices. 
• Difficult to control weeds may require sequential applications, such as a broad 
spectrum preemergence herbicide followed by one or more postemergence 
herbicide applications. Utilize herbicides containing different modes of action 
effective on the target weeds in sequential applications. 
Do not overuse the technology 
• Do not use more than two applications of this or any other herbicide with the 
same mode of action in a single growing season unless mixed with an herbicide 
with a different mode of action which provides overlapping spectrum for the 
difficult to control weeds. 
Scout and inspect fields following application 
• Prevent an influx of weeds into the field by controlling weeds in field borders. 
• Scout fields after application to verify that the treatment was effective. 
 
• Suspected- herbicide resistant weeds may be identified by these indicators 
• Failure to control a weed species normally controlled by the herbicide at the dose 
applied, especially if control is achieved on adjacent weeds; 
• A spreading patch of non-controlled plants of a particular weed species; and 
• Surviving plants mixed with controlled individuals of the same species. 
• Report non-performance of this product to your Syngenta retailer, Syngenta 
representative, or call 1-866-Syngent(a) (
866-796-4368). If resistance is suspected 
ensure weed escapes are controlled using an herbicide with an effective mode of 
action and/or use non-chemical means to prevent further seed production.

Orion Herbicide 
Page 9 
 
Prevent weed escapes before, during, and after harvest 
• Do not allow weed escapes to produce seed or vegetative structures such as 
tubers or stolons which contribute to spread and survival. Consider harvest 
weed seed management and control weeds post-harvest to prevent seed 
production. 
Resistant Weeds 
• Contact your local Syngenta representative, retailer, crop advisor or extension 
agent to determine if weeds resistant to modes of action contained in this product 
are present in your area. Do not assume that each listed weed is being controlled 
by multiple modes of action. Premixes are intended to broaden the spectrum of 
weeds that are controlled. Some weeds may be controlled by only one of the 
active ingredients in this product. If resistant biotypes have been reported, use 
the full labeled rate of this product, apply at the labeled timing, and tank-mix with 
an additional different mode of action product so there are multiple effective 
modes of application for each suspected resistant weed. 
 
Crop Rotation Intervals 
 
The following rotational crops may be planted at the indicated interval following 
application of Orion Herbicide. 
 
 
Crop 
Rotation Interval 
(Months) 
Barley, grasses, oats, rye, triticale, wheat 1 
Field corn, popcorn, seed corn, sweet corn, sorghum 3 
Alfalfa, canola, chickpea, soybean, dry bean, pea (dry and 
succulent), flax, lentil, potato, safflower, sugar beet, sunflower 
9 
Other crops not listed 12 
 
Avoiding Injurious Spray Drift 
 
This product can affect broadleaf plants directly through foliage and indirectly by root 
uptake from treated soil. Do not apply Orion Herbicide directly to, or allow spray drift to 
come into contact with, broadleaf crops including, but not limited to, alfalfa, canola, 
beans, cotton, flowers, grapes, lettuce, lentils, mustard, peas, potatoes, radishes, 
soybeans, sugar beets, sunflowers, tobacco, tomatoes, vegetables, or other desirable 
broadleaf crops or ornamental plants or soil where sensitive crops will be planted the 
same season. (See Crop Rotation Intervals section.) 
 
Make applications only when there is little or no hazard from spray drift. Very small 
quantities of spray, which may not be visible, may seriously injure crops, whether 
dormant or actively growing. When applying Orion Herbicide, use low pressure 
equipment capable of producing sprays of uniform droplet size with a minimum of a 
medium-quality spray. Under adverse weather conditions, fine spray droplets that do

Orion Herbicide 
Page 10 
 
not settle rapidly onto target vegetation may be carried a considerable distance from the 
treatment area. A drift control or spray thickening agent may be used with this product 
to improve spray deposition and minimize the potential for spray drift. If used, follow all 
use recommendations and precautions on the product label. 
 
Ground Applications: To minimize spray drift, apply Orion Herbicide in a total spray 
volume of 8 gallons or more per acre. Refer to the spray equipment manufacturer's 
recommendations for detailed information on nozzle types, arrangement, spacing and 
operating height and pressure. Spot treatments should be applied only with a calibrated 
boom to prevent over application. Operate equipment at spray pressures no greater 
than is necessary to produce a uniform spray pattern. Operate the spray boom no 
higher than is necessary to produce a uniformly overlapping pattern between spray 
nozzles. Do not apply with hollow cone-type nozzles or other nozzles that produce a 
fine-quality spray. 
 
Aerial Application: To minimize spray drift, apply Orion Herbicide in a total spray 
volume of 3 gallons or more per acre. Drift potential is lowest between wind speeds of 2 
to 10 mph. However, many factors, including droplet size and equipment type, 
determine drift potential at any given speed. Spray drift from aerial application can be 
minimized by applying a coarse spray at spray boom pressure no greater than 30 psi, 
and by using straight-stream nozzles directed straight back. Spray pattern and droplet 
size distribution can be evaluated by applying sprays containing a water-soluble dye 
marker or appropriate drift control agents over a paper tape (adding machine tape). 
 
Mechanical flagging devices may be used.

Orion Herbicide 
Page 11 
 
 
SPRAY DRIFT MANAGEMENT 
 
MANDATORY SPRAY DRIFT MANAGEMENT 
Aerial Applications: 
• Do not release spray at a height greater than 10 ft above the ground or vegetative 
canopy, unless a greater application height is necessary for pilot safety. 
• Applicators are required to use a medium or coarser droplet size according to the most 
current version of the American Society of Agricultural & Biological Engineers Standard 
641 (ASABE S641). 
• If the windspeed is 10 miles per hour or less, applicators must use ½ swath 
displacement upwind at the downwind edge of the field. When the windspeed is 
between 11 – 15 miles per hour, applicators must use ¾ swath displacement upwind at 
the downwind edge of the field. 
• Do not apply when wind speeds exceed 15 mph at the application site. If the 
windspeed is greater than 10 mph, the boom length must be 65% or less of the 
wingspan for fixed wing aircraft and 75% or less of the rotor diameter for helicopters. 
Otherwise, the boom length must be 75% or less of the wingspan for fixed-wing aircraft 
and 90% or less of the rotor diameter for helicopters. 
• Do not apply during temperature inversions. 
 
Ground Boom Applications: 
• User must only apply with the release height recommended by the manufacturer, but 
no more than 3 feet above the ground or crop canopy. 
• Applicators are required to use a medium or coarser droplet size according to the most 
current version of the American Society of Agricultural & Biological Engineers Standard 
572 (ASAE S572). 
• Do not apply when wind speeds exceed 15 miles per hour at the application site. 
• Do not apply during temperature inversions. 
 
SPRAY DRIFT ADVISORIES 
 
THE APPLICATOR IS RESPONSIBLE FOR AVOIDING OFF-SITE SPRAY DRIFT. BE 
AWARE OF NEARBY NON-TARGET SITES AND ENVIRONMENTAL CONDITIONS. 
 
IMPORTANCE OF DROPLET SIZE 
 
An effective way to reduce spray drift is to apply large droplets. Use the largest droplets 
that provide target pest control. While applying larger droplets will reduce spray drift, the 
potential for drift will be greater if applications are made improperly or under unfavorable 
environmental conditions. 
 
Controlling Droplet Size - Ground Boom 
 
• Volume - Increasing the spray volume so that larger droplets are produced will 
reduce spray drift. Use the highest practical spray volume for the application. If a

Orion Herbicide 
Page 12 
 
greater spray volume is needed, consider using a nozzle with a higher flow rate. 
 
• Pressure - Use the lowest spray pressure recommended for the nozzle to produce 
the target spray volume and droplet size. 
 
• Spray Nozzle - Use a spray nozzle that is designed for the intended application. 
Consider using nozzles designed to reduce drift. 
 
Controlling Droplet Size – Aircraft 
 
• Adjust Nozzles - Follow nozzle manufacturer’s recommendations for setting up 
nozzles. Generally, to reduce fine droplets, nozzles should be oriented parallel with 
the airflow in flight. 
 
BOOM HEIGHT – Ground Boom 
 
Use the lowest boom height that is compatible with the spray nozzles that will provide 
uniform coverage. For ground equipment, the boom should remain level with the crop 
and have minimal bounce. 
 
RELEASE HEIGHT – Aircraft 
 
Higher release heights increase the potential for spray drift. When applying aerially to 
crops, do not release spray at a height greater than 10 ft above the crop canopy, unless 
a greater application height is necessary for pilot safety. 
 
 
SHIELDED SPRAYERS 
 
Shielding the boom or individual nozzles can reduce spray drift. Consider using 
shielded sprayers. Verify that the shields are not interfering with the uniform deposition 
of the spray on the target area. 
 
TEMPERATURE AND HUMIDITY 
 
When making applications in hot and dry conditions, use larger droplets to reduce 
effects of evaporation. 
 
TEMPERATURE INVERSIONS 
 
Drift potential is high during a temperature inversion. Temperature inversions are 
characterized by increasing temperature with altitude and are common on nights with 
limited cloud cover and light to no wind. The presence of an inversion can be indicated 
by ground fog or by the movement 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. Avoid applications during temperature

Orion Herbicide 
Page 13 
 
inversions. 
 
WIND 
 
Drift potential generally increases with wind speed. AVOID APPLICATIONS DURING 
GUSTY WIND CONDITIONS. 
Applicators need to be familiar with local wind patterns and terrain that could affect 
spray drift. 
 
SENSITIVE AREAS 
The pesticide should only be applied when the potential for drift to adjacent sensitive 
areas (e.g., residential areas, bodies of water, known habitat for threatened or 
endangered species, non-target crops) is minimal (e.g., when wind is blowing away 
from the sensitive areas). 
 
MIXING 
 
Mixing Orion Herbicide Alone 
 
1. Fill the tank with ½ of the total amount of water. 
2. Start agitation. 
3. Add the required amount of Orion Herbicide. 
4. Continue agitation while filling the spray tank to the required volume. 
5. To ensure a uniform spray mixture, continuous agitation is required during 
application. If product is allowed to settle, thoroughly agitate to resuspend the 
mixture before spraying. Apply mixture immediately after it is prepared. 
 
Orion Herbicide Applied in Tank-Mix Combination 
 
If a broader spectrum of weed control is needed, Orion Herbicide may be tank mixed 
with labeled rates of other herbicides provided (1) the tank-mix product is labeled for the 
timing and method of application for the use site to be treated; and (2) tank mixing is not 
prohibited by the label of the tank-mix product. It is the pesticide user’s responsibility to 
ensure that all products in the listed mixtures are registered for the intended use. Users 
must follow the most restrictive directions for use and precautionary statements of each 
product in the tank mixture. 
 
Tank Mixing Precautions 
 
• Read carefully and follow all applicable use directions, precautions, and limitations 
on the respective product labels. 
• Do not exceed recommended application rates for respective products or maximum 
allowable application rates for any active ingredient in the tank mix. 
• Always perform a (jar) test to ensure the compatibility of products to be used in tank 
mixture.

Orion Herbicide 
Page 14 
 
Tank-Mix Compatibility Testing: A jar test is recommended prior to tank mixing to 
ensure compatibility of Orion Herbicide and other pesticides. Use a clear glass quart jar 
with lid and mix the tank mix ingredients in their relative proportions. Invert the jar 
containing the mixture several times and observe the mixture for approximately ½ hour. 
If the mixture balls-up, forms flakes, sludges, gels, oily films or layers, or other 
precipitates, it is not compatible and the tank-mix combination should not be used. 
 
Vigorous, continuous agitation during mixing, filling and throughout application is 
required for all tank mixes. Sparger pipe agitators generally provide the most effective 
agitation in spray tanks. To prevent foaming in the spray tank, avoid stirring or 
splashing air into the spray mixture. 
 
Mixing Order for Tank Mixes 
 
1. Fill the spray tank to ¾ of the total spray volume required with water. 
2. Start agitation. 
3. Add Orion Herbicide and agitate for 2 to 3 minutes. 
4. After adding Orion Herbicide, add different formulation types in the following 
order: (1) dry flowables; (2) wettable powders; (3) aqueous suspensions, 
flowables and liquids. Maintain agitation and add: (4) emulsifiable concentrates; 
(5) solutions; and (6) adjuvants. Allow time for complete mixing and dispersion 
after each addition. 
5. Finish filling the spray tank. Maintain continuous agitation during mixing and 
throughout application. If product is allowed to settle, thoroughly agitate to 
resuspend the mixture before spraying. Apply mixture immediately after it is 
prepared. 
 
If application or agitation must be stopped before the spray tank is empty, the materials 
may settle to the bottom. Settled materials must be resuspended before spraying is 
resumed. A sparger agitator is particularly useful for this purpose. Settled material may 
be more difficult to resuspend than when originally mixed. 
 
Cleanout Procedures for Spray Equipment 
 
1. Drain any remaining spray mixture from the application equipment. 
2. Hose down the interior surfaces of the tank while filling the tank ½ full of water. 
3. Add household ammonia at a rate of 1 gallon per 100 gallons of water. 
Recirculate for 5 minutes and spray out part of this mixture for 5 minutes through 
the boom. Drain tank. 
4. Remove all spray nozzles and screens and clean separately. 
5. If spray equipment will be used for pesticide application to crops sensitive to 
Orion Herbicide, steps 1-3 should be repeated. Exterior surfaces of spray 
equipment should also be thoroughly cleaned. 
 
Note: Rinsate may be disposed of on site according to label use directions or at an 
approved waste disposal facility.

Orion Herbicide 
Page 15 
 
Weeds Controlled or Suppressed by Orion Herbicide 
 
Weeds Controlled 
buckwheat, wild mustard, black 
canola, volunteer1 mustard, blue (purple) 
chamomile, corn mustard, tans y 
chamomile, false (scentless) mustard, treacle (bushy wallflower) 
chamomile, mayweed (dogfennel) mustard, tumble (Jim Hill) 
chamomile, wild mustard, wild 
chickweed, common penn ycress, field 
cleavers (catchweed bedstraw) pi gweed, redroot3 
fiddleneck, coast 
flixweed
2 
pineappleweed 
prickl
y lettuce2 
hempnettle3 ra gweed, common 
knotweed shepherdspurse 
lambsquarters smartweed 
(green, ladysthumb, Pennsylvania) 
London rocket sunflower, annual 2 
Weeds Suppressed4 
burdock2 
dandelion (seedlings and overwintered 
rosettes <6 inches in diameter)3 
plantain (top growth) 
sowthistle, annual 
sowthistle, perennial 
filaree, redstem3 thistle, Canada 3 
 
1Including all herbicide-tolerant canola varieties. 
2Up to the 4-leaf stage. 
3Improved control can be achieved with the addition of 1 oz ae per acre of MCPA ester 
(2.2 fl oz per acre of a 3.7 lb ae per gallon of a MCPA ester product). 
4Weeds Suppressed means significant activity but not always at a level considered 
acceptable for commercial weed control. 
 
APPLICATION DIRECTIONS 
 
Application Timing 
 
Apply Orion Herbicide early postemergence to actively growing weeds. Extreme 
growing conditions such as drought or near freezing temperatures prior to, at, or 
following time of application may reduce weed control and increase the risk of crop 
injury at all stages of growth. Only weeds that have emerged at the time of 
application will be controlled. If foliage is wet at the time of application, control may 
be decreased. Applications of Orion Herbicide are rainfast within 4 hours after 
application. 
 
Spray Coverage 
 
Use sufficient spray volume to provide thorough coverage and a uniform spray pattern. 
Do not broadcast apply in less than 3 gallons of total spray volume per acre. For best 
results and to minimize spray drift, apply in a spray volume of 10 gallons or more per

Orion Herbicide 
Page 16 
 
acre. As vegetative canopy and weed density increase, spray volume should be 
increased to obtain equivalent weed control. Use only nozzle types and spray 
equipment designed for herbicide application. To reduce spray drift, follow precautions 
under Avoiding Injurious Spray Drift. 
 
Adjuvants 
 
Generally this product does not require the use of an adjuvant to achieve satisfactory 
weed control. An adjuvant may be added to optimize herbicidal activity when 
applications are made at lower carrier volumes; under conditions of cool temperature, 
low relative humidity or drought; or when a tank-mix partner recommends the use of an 
adjuvant. 
 
When an adjuvant is to be used with this product, the use of an adjuvant that meets the 
standards of the Chemical Producers and Distributors Association (CPDA) adjuvant 
certification program is recommended. 
 
Wheat (Including Durum), Barley, Oats, Rye, Triticale 
 
Apply 17 fl oz of Orion Herbicide per acre to actively growing wheat (including spring, 
winter and durum), barley, oats, rye and triticale from the 3-leaf crop growth stage up to 
the joint stage (Zadoks scale 31). Apply when weeds are actively growing. Only weeds 
emerged at the time of treatment will be controlled. Best results are obtained from 
application made to seedling weeds. A later application when the crop is between the 
jointing and boot stage of growth may be used to control later emerging weeds; 
however, do not apply unless the risk of injury is acceptable. Do not apply after the boot 
stage. 
 
Warm, moist growing conditions promote active weed growth and enhance the activity 
of Orion Herbicide by allowing maximum foliar uptake and contact activity. Weeds 
hardened off by cold weather or drought stress may not be adequately controlled or 
suppressed and regrowth may occur. For best results, ensure thorough spray coverage 
of target weeds. 
 
Tank Mixtures for Wheat (Including Durum): Orion Herbicide may be applied in 
tank-mix combination with labeled rates of other products registered for postemergence 
application in wheat. See Tank Mixing Precautions under Mixing. When tank mixing, 
do not exceed recommended application rates and use only in accordance with the 
most restrictive precautions and limitations on the respective product labels. It is the 
pesticide user’s responsibility to ensure that all products in the listed mixtures are 
registered for the intended use. Users must follow the most restrictive directions for use 
and precautionary statements of each product in the tank mixture. 
 
Restrictions 
 
• Do not make more than one application per year. 
• Do not apply more than 17 fl oz of Orion Herbicide per acre per year.

Orion Herbicide 
Page 17 
 
• Livestock may be grazed on treated crops 7 days following application. 
• Preharvest Interval: Do not apply within 60 days of crop harvest. 
• Do not exceed 0.75 lb ae of MCPA or 0.0044 lb ai of florasulam per acre per year 
from all combined uses. 
 
STORAGE AND DISPOSAL 
 
Do not contaminate water, food, or feed by storage or disposal. 
 
Pesticide Storage 
 
Store in original container only. Storage below 14°F will cause the product to freeze. If 
product freezes, bring to room temperature and agitate before use. 
 
Pesticide Disposal 
 
Improper disposal of excess pesticide, spray mixture or rinsate is a violation of Federal 
Law. If these wastes cannot be disposed of by use according to label instructions, 
contact your State Pesticide or Environmental Control Agency, or the Hazardous Waste 
Representative at the nearest EPA Regional Office for guidance. 
 
Container Handling 
 
Container Handling [less than or equal to 5 gallons] 
Non-refillable container. Do not reuse or refill this container. Triple rinse container (or 
equivalent) promptly after emptying. Triple rinse as follows: Empty the remaining 
contents into application equipment or a mix tank and drain for 10 seconds after the flow 
begins to drip. Fill the container ¼ full with water and recap. Shake for 10 seconds. 
Pour rinsate into application equipment or a mix tank or store rinsate for later use or 
disposal. Drain for 10 seconds after the flow begins to drip. Repeat this procedure two 
more times. Then offer for recycling if available or puncture and dispose of in a sanitary 
landfill, or by incineration, or by other procedures approved by state and local 
authorities. 
 
Container Handling [greater than 5 gallons] 
Non-refillable container. Do not reuse or refill this container. Triple rinse container (or 
equivalent) promptly after emptying. Triple rinse as follows: Empty the remaining 
contents into application equipment or a mix tank. Fill the container ¼ full with water. 
Replace and tighten closures. Tip container on its side and roll it back and forth, 
ensuring at least one complete revolution, for 30 seconds. Stand the container on its 
end and tip it back and forth several times. Turn the container over onto its other end 
and tip it back and forth several times. Empty the rinsate into application equipment or 
a mix tank or store rinsate for later use or disposal. Repeat this procedure two more 
times. Then offer for recycling if available or puncture and dispose of in a sanitary 
landfill, or by incineration, or by other procedures approved by state and local 
authorities.

Orion Herbicide 
Page 18 
 
Container Handling [greater than 5 gallons] 
Refillable container. Refill this container with pesticide only. Do not reuse this container 
for any other purpose. Cleaning the container before final disposal is the responsibility 
of the person disposing of the container. Cleaning before refilling is the responsibility of 
the person refilling. To clean container before final disposal, empty the remaining 
contents from this container into application equipment or mix tank. Fill the container 
about 10 percent full with water. Agitate vigorously or recirculate water with the pump 
for 2 minutes. Pour or pump rinsate into application equipment or rinsate collection 
system. Repeat this rinsing procedure two more times. Then offer for recycling if 
available or puncture and dispose of in a sanitary landfill, or by incineration, or by other 
procedures approved by state and local authorities. 
 
For minor spills, leaks, etc., follow all precautions indicated on this label and clean up 
immediately. Take special care to avoid contamination of equipment and facilities during 
cleanup procedures and disposal of wastes. In the event of a major spill, fire, or other 
emergency, call 1-800-888-8372, day or night. 
 
CONTAINER IS NOT SAFE FOR FOOD, FEED, OR DRINKING WATER. 
 
Orion® and the Syngenta Logo are Trademarks of a Syngenta Group Company. 
 
©20XX Syngenta 
 
 
For non-emergency (e.g., current product information), call 
Syngenta Crop Protection at 1-800-334-9481 
 
 
Manufactured for: 
Syngenta Crop Protection, LLC 
P.O. Box 18300 
Greensboro, North Carolina 27419-8300 
 
Orion 1307 MAS 0616 AMEND-E FEB2020-CL – ep – 10-22-25 
000100-01307.2020214E.ORION-AMEND-FEB2020-CL