Chemical Control

Chemical Control Contents

• Which herbicide do I use?
• Specific Herbicides on Specific Noxious Weeds
  • Musk thistle & Scotch thistle
  • Leafy Spurge
  • Diffuse knapweed & Yellow Starthistle
  • Dalmatian Toadflax
  • Whitetop or Hoary Cress
  • Orange and Meadow Hawkweed
  • Common Mullein
  • Houndstongue
  • Canadian Thistle
  • Kochia & Russian Thistle
• Calibration Guides
  • Calibrating Equipment
  • Calibration Formulas
  • Adequate Recordkeeping
• Okanogan County Commercial Applicators
  And Bid Prices

• Useful Tables and Charts
  • Liquid
  • Dry Weight
  • Mix for spot treatment
  • Calibration of Equipment
  • Tips!!!

WHICH HERBICIDE DO I USE?

• The key to successful herbicide application is adding the correct SURFACTANT!!!
• Use 1 Quart Surfactant per/100 gallons of Water or follow the label recommendation.
• To use 'Restricted Use Herbicides,' you must have a current Pesticide License for the State of Washington. There are 3 license categories to choose from, to fit your specific management needs on your property.

ALWAYS, READ and FOLLOW THE HERBICIDE LABEL!

SAFETY, FIRST!  LAST!  and  ALWAYS!!!

Specific Herbicides on Specific Noxious Weeds:

• Musk Thistle & Scotch Thistle
  (Spring and Fall applications are the best window of timing. For mature plants, Curtail or Tordon + Surfactant will give the best results.)
  • CURTAIL @ 2 Quarts per/acre + Surfactant
  • TORDON @ 1-1/2 Pints per/acre + 1 Pint of 2,4-D per/acre + Surfactant
  • BANVEL @ 1 to 1-1/2 Pint per/acre + Surfactant
  • REDEEM@ 1-1/2 Pint per/acre + Surfactant
    
• Leafy Spurge
  (Treat in full bloom to post bloom/regrowth, better control results if mature plants)
  • ESCORT @ 1 to 1-1/2 oz per/acre + 2 Quarts 2,4-D + Silicone Surfactant @ 1 Quart per/100 gallon WATER
  •  PLATEAU @ 12 oz per/acre + Surfactant, apply late Fall for best results
  • TELAR @ 1-2 oz per/acre + Surfactant
    
• Diffuse Knapweed & Yellow Starthistle (knapweed family)
  • TORDON @ 1-1/2 Pint per/acre + 1-1/2 Pint 2,4-D + Surfactant
  • CURTAIL @ 2 Quarts per/acre + Surfactant
  • TRANSLINE @ 1 Pint per/acre + Surfactant
    (recommended in forest/timber sites)
  • BANVEL @ 1 Pint per/acre + 2,4-D @ 2 Pints per/acre + Surfactant
  • REDEEM @ 1-1/2 Pint per acre + Surfactant
    

• Dalmatian Toadflax
  (Treat in full bloom stage in spring and post bloom very late fall for best results & wet entire plant)
  (Toadflax has a waxy leaf surface, silicone surfactant is the MOST important additive to any Herbicide mixture to insure results!)
  • ESCORT @ 1-2 oz per/acre + 2,4-D @2 Pints per/acre + Silicone Surfactant
  • TELAR @ 1-1/2 to 2 oz per/acre + 2,4-D @ 2 Pints per/acre + surfactant
  • PLATEAU @ 8-12 oz per/acre + MSO & silicone surfactant
    
• Whitetop or Hoary Cress
  (treat in full bloom & fall re-growth)
  • TELAR @ 3/4 to 1oz per/acre + Surfactant
  • ESCORT @ 1/2 to 1 oz per/acre + Silicone Surfactant
  • PLATEAU @ 8-12 oz per/acre + MSO
    
• Orange and Meadow Hawkweed
  • TORDON @ 1 Pint per/acre + 2,4-D @ 1 Pint + Surfactant
  • TRANSLINE @ 1 Pint per/acre + Surfactant
    (use on forest sites)
  • CURTAIL @ 1 Quart per/acre + Surfactant
  • REDEEM @1-1/2 Pint  per/acre + Surfactant
• Common Mullein
  (treat in rosette stage, early Spring)
  • TORDON @ 2 Pints per/acre + 2,4-D @ 2 Pints + MSO +  Silicone Surfactant
  • TORDON @ 1-1/2 Pints + BANVEL @ 1-1/2 Pints + MSO + Silicone Surfactant
  • ESCORT @ 1 oz per/acre + MSO + Silicone Surfactant
    
• Houndstongue

  (prefer rosette stage)

  • PLATEAU @ 8 oz per/acre + MSO
  • ESCORT @ 1 oz per/acre + MSO + Surfactant
  • TORDON @ 1 Pint per/acre + 2,4-D @ 1 to 2 pints per/acre + MSO + Surfactant
  • BANVEL @ 2 Pints per/acre + 2,4-D @ 2 pints per/acre + MSO  Surfactant
  • CURTAIL @ 2Quarts per/acre + Surfactant
    
• Canadian Thistle
  (apply in active growing stage or full bloom/fall; this is the only thistle that is a perennial)
  • BANVEL @ 1-1/2 pints per/acre + 2,4-D @ 2 pints per/acre + surfactant
  • CURTAIL @ 1 to 2 Quarts per/acre + Surfactant
  • RODEO @ 1 Quart per/acre + LI700 surfactant, need an aquatic license for applying in or near any water or wetland areas.
    
• Kochia & Russian Thistle and sometimes Russian Knapweed
  • These are Herbicide resistant weeds to most chemical formulations, we recommend to use the sulfonylureas inhibitors such as: ESCORT, TELAR, ALLY, OUST, HARMONY, EXTRA, GLEAN,  FINESSE, PLATEAU, CURTAIL and TORDON, call us for rates.
  • BANVEL (also works well on Kochia) @ 2 Pints per/acre + Surfactant.
  • KOCHIA apply at early stage of growth for best results 4" to 6" in height. Follow the label instructions for rate per/acre. RUSSIAN THISTLE apply at rossette stage. RUSSIAN KNAPWEED apply at bud to full bloom.

Some Herbicides can be purchased and applied without a Pesticide license. Although more choices have been made available, we do recommend obtaining your Pesticide License for the education and safety training.  These are offered at our Re-certification classes during the Fall. See our office for Labels, recommendations and mode of action for each Herbicide. Follow Label directions and instructions carefully!

The following Herbicides are listed for individuals without a pesticide license:

• 2, 4-D, 1 gallon per person
• Redeem
• Round-up
• Escort
• Plateau
• Telar
• Curtail, 1 gallon per person

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CALIBRATION GUIDE

Checklist for Applying Noncrop Herbicides:

In order to ensure good herbicide performance and eliminate off-target injury, consideration must be given to many factors before an herbicide application is made. The following checklist should be used in developing a safe and effective noncrop herbicide program.

Application Accuracy

• Select the proper equipment for the spray job.
• Use the best nozzle type and check for replacement if worn.
• Calibrate periodically for spray output accuracy.
• Use as low a pressure as practical to reduce drift.
• Use of drift control agents is recommended.
• Limit speed to 15 mph or less.
• License and certify application personnel as necessary.
• Maintain detailed spray records of all treatments, according to State Law.

Chemical Selection

• Understand the solubility, mobility and persistence properties of the herbicides to be used for a job.
• Match the herbicide to be used with the target weed species.
• Select an adequate rate of product.
• Determine if the site requires an aquatic or terrestrial type of product.
• Consider local issues and restrictions before selecting the herbicide for a job.
• Consider the sensitivity of adjacent crops or plants to the products to be used.

Safety Considerations

• Consider local wind, temperature and humidity conditions before making the application.
• Consider shallow groundwater conditions on the site.
• Avoid applications to saturated or frozen soils, or just prior to a heavy rainfall.
• Do not make herbicide treatments on steep slopes where rainfall may move the herbicide to non-target areas.
• Protect waterways, irrigation and potable water supplies and domestic wells from possible chemical contamination.
• Dispose of used containers by following label instructions or applicable state laws.
• Always read the entire label before application.
• Be cautious with dirt or gravel road treatments.
• Avoid mechanical operations that disturb treated soil.
• Develop good public relations and attitudes.
• Consider agricultural crops. Avoid side-by-side treatment with crops or other sensitive vegetation.
• Maintain stable buffer areas or physical barriers between sensitive vegetation.
• Look out for tree or plant roots growing into a treatment area.

Calibrating Equipment

• New nozzles should be utilized to provide a uniform spray swath. Calibrate with a drift agent to ensure proper output. Use large nozzles mounted close to the ground to reduce drift.
• Drift agents should always be used to reduce off-target drift next to sensitive vegetation.
• Surfactants should be used when green growth is present.
• Select and maintain proper ground speed.
• Continuous agitation provides a uniform mixture.
• Use of dyes and colorants is beneficial when using handguns or spot spraying in difficult areas to mark or the possibility of missing plants.
• Weather, winds greater than 10 MPH, temperatures higher than 85 degrees F, and humidity less than 20% can lead to severe off-target problems.
• Proper cleanup ensures repeated high efficiency applications and reduced tank contamination.
• Records must be provided on all applications to provide a retrievable spray record. We have forms in our office to supply to you.
• Be sure all nozzles on boom are of the same type and size!
• Fill spray tank with clean water and prime the spray system before calibrating.
• Check for leaks and plugged nozzles.
• Check nozzle output uniformity by operating sprayer and collecting water from each nozzle for 60 seconds, (determine oz per minute for each nozzle). Replace nozzles as necessary.

After each day's use, thoroughly flush with water both inside and out, to prevent accumulation of chemicals. Use an appropriate cleaning agent to flush tank and boom. Very important to keep all machinery clean and flushed!!

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CALIBRATION FORMULAS

 Boom and Boomless Sprayers

1. Fill the spray tank with water.
2. Run the sprayer at operating pressure (25-35psi). Use good nozzles to uniformly cover the desired swath width. Measure the swath width (SW) in feet.
3.  Collect the spray volume from the nozzles and measure the exact amount caught in 1 (one) minute. Record the amount in gallons per minute (GPM).

4. Determine the sprayer speed (MPH) over a 200 foot distance. Maintain the desired speed and measure in seconds (SECS) the time the sprayer takes to travel the 200-foot distance.

5. Determine the gallons per acre (GPA).

6. Calculate the amount of chemical needed per tank.

B. Stationary Method

1. Fill the spray tank approximately 1/2 full with clean water. If a drift control agent will be used during the application, calibrate with that agent.
2. Measure the spray pattern width in inches.
3.  Collect the spray output from the nozzles for 1 minute. Measure the volume collected in fluid ounces and divide by 128 to determine gallons per minute (GPM).
4.  Select the speed, in miles per hour, that will be used for spraying.
5. Determine the gallons per acre (GPA) being applied, using a large output nozzle or a cluster of nozzles.

   Gallons per acre =	5940 X gallons per minute
   (GPA)	MPH X width in inches

OR

6. Chemical needed =

C. Backpack Sprayer (Spot Treatment)

1. Establish a calibration plot that is exactly
   18.5 feet wide X 18.5 feet long
2. Spray the calibration plot uniformly with water, noting the number of seconds required.
   
   Time Required = ________ of seconds.
   
3. Spray into a bucket for the same number of seconds.
4.  Measure the number of ounces of water in the bucket.

   Volume Sprayed = ______ of ounces.
   

5. The number of ounces collected from the bucket is equal to the number of gallons per acre the sprayer is delivering.

Gallons Per Acre (GPA) = ________

D. Calculation of Gallons Per Acre

# of Acres X Rate of Herbicide (pints or ounces) = # of pints or ounces by pints per gallon or ounces per gallon to = # of gallons needed for amount of acres. Example: 20 acres X 1.5 pints = 30 pints ( 8 pints per/gal = 3.75 gallons to use.

E. Charts

1 Gallon = 4 quarts - 8 pints - 16 cups - 128 ounces

1 Quart = 2 pints - 4 cups - 32 ounces

1 Pint = 2 cups - 16 ounces

1 Cup = 8 ounces

1 Ounce = 2 tablespoons

1 Tablespoon = 3 teaspoons

Dilution Rates:

Approximate quantity of liquid material to be added to various quantities of water to get certain dilutions.

F. Adequate Recordkeeping

Thirteen Pesticide application facts are required for Recordkeeping.

1. Name: The name and address of the person for whom the pesticide was applied or own use.
2. Location: The address or exact location of the land where the pesticide was applied.
3. Time: The year, month, day and beginning and ending times of the application of the pesticide.
4. Pesticide: The product name on the pesticide label and Environmental Protection Agency registration number (EPA Reg. NO.), if applicable, of the pesticide that was applied.
5. Weather Conditions: The direction from which the wind was blowing, estimated velocity of the wind, and the temperature at the time the pesticide was applied.
6. Amount: The total amount of pesticide applied (gallons, pounds, ounces, etc.).
7. Rate: The amount of pesticide applied (pounds or gallons) per acre, per 1,000 square feet or other measurement.
8. Concentration: The pesticide concentration that was applied. Liquid applications may be recorded as the amount of product per 100 gallons of spray, or other appropriate measure, i.e. gallons per acre.
9. Pest: The pests to be controlled (for Pest Control Operator classification only.)
10. Site: The crop or site to which the pesticide was applied.
11. Apparatus: The apparatus license plate number, if applicable.
12. Applicators' name: the licensed applicator's name, license number, and the name and license number of the individual making the application, (if different).
13. Area: The number of acres or other appropriate measure, to which the pesticide was applied.

Our weed office has 2 different forms available for your spray records, one for weed control and one for orchard or agriculture use form. You can also call the Dept of Ag at the Wenatchee office for any specific questions or forms.

Commercial Applicators

Weed Control

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USEFUL TABLES and CHARTS

LIQUID

1 Gallon = 4 Quarts or 8 Pints, 16 Cups, 128 oz
1 Quart = 2 pints
1 Pint = 2 Cups
1 Cup = 8 Ounces or 16 Tablespoons
1 Ounce = 2 Tablespoons
3 Teaspoons = 1 Tablespoon

DRY WEIGHT

1 Ounce = 28.4 Grams
16 Ounce = 1 Pound
1 Pound = 454 Grams
1 Kilogram = 2.2 Pounds

MIX FOR SPOT TREATMENT

1% Solution per/100 Gallons = 1 Gal/Herbicide
1% Solution per 3 Gallons = 3.8 oz Herbicide
1% Solution per/1 Gallon = 1.3 oz/4 Tbsp/Herbicide
2% Solution per/1 Gallon = 2.5 oz/4 Tbsp/Herbicide

At 1 Quart or 2 Pints per/acre rate of Herbicide, with 1 gallon of water, add; 3.3 Tbsp of Herbicide + Surfactant (1 Tblsp)

CALIBRATION OF EQUIPMENT

Acres treated x Rate of Product = total volume

Divide by 8 Pints/per Gallon = # of total gallon

TIPS!!

• Always use Clean Water!!
• Check and Clean equipment after every use!
• Wear Safety clothing, boots, and gloves!
• Calibrate sprayer and follow label instructions!

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