Monterey Weed Impede (Surflan Herbicide) - Questions & Answers

The Weed Impede product label does recommend that you use either a handheld sprayer or a backpack sprayer to get even coverage and this would be our recommendation as well. The amount of Weed Impede you will use will vary depending on what weeds you are trying to prevent and what season you are treating in but in general you will need 1-12 fl oz per 1,000 sq ft of area to be treated. According to the Weed Impede product label:

"The amount of water used to apply WEED IMPEDE™ herbicide is not critical, but should be sufficient for uniform coverage of the target area. Calibrate by determining the volume of water required to treat 1,000 square feet. Use this calibration volume to determine the amount of water and WEED IMPEDE™ herbicide needed to treat the target area (see the following calibration example). Note: Sprayer calibration (volume of spray needed to treat 1,000 square feet) will vary with each individual operator.
Steps in Calibration:
1. Mark an area of 1,000 square feet (i.e. 20 by 50 feet or 25 by 40 feet).
2. Place the sprayer on a level surface and add water noting the final level of water in the spray tank.
3. Spray the marked area with a sufficient volume of water to provide uniform coverage. Refill the sprayer to the same level as before measuring the amount of water added. The measured water added to the sprayer is the volume needed to cover 1,000 square feet.
4. Determine the application rate (fl. oz./1,000 sq. ft.) for WEED IMPEDE™ from the Recommendations section of this label.
5. To each volume of water used as measured in step 3, add the amount of WEED IMPEDE™ as determined in step 4.
Example: If the sprayer uses 2 gallons of water to cover 1,000 square feet and the desired application rate of WEED IMPEDE™ is 3 fluid oz./1,000 square feet, then you would add 3 fluid ounces of WEED IMPEDE™ to every 2 gallons of water to be used."

Monterey Weed Impede (Surflan Herbicide) is indeed a bright orange liquid product.

Pets can return to the area once dry, typically a few hours is best after applying Monterey Weed Impede to ensure the area is thoroughly dry.

Monterey Weed Impede is not labeled to control dandelions. Fertilome Broadleaf Weed Control with Gallery is labeled to control dandelions and may better meet you needs.

Monterey Weed Impede (Surflan Herbicide) is labeled for applications around established Iris and Rose of Sharon. Please check the product label list for tolerable plant species on page 3 and application instructions.

The active ingredient Oryzalin in Monterey Weed Impede is known to be used as a pre-emergent for Sandburs. Your best control begins in mid-February with a pre-emergence herbicide application. Follow the label, and treat again as needed.

Application timing will vary by region and the best person to ask about application timing is your local master gardener who works at your local cooperative extension office.

Cooperative Extension Locator:

http://npic.orst.edu/pest/countyext.htm

Yes, Monterey Weed Impede Herbicide will prevent puncturevine and many other common broadleaf weeds from germinating. Be sure to activate with rainfall or irrigation within 21 days of application, in accordance with the product lablel.

According to the Weed Impede product label: Herbicides that control annual weeds may also affect establishment of desirable turfgrass seedlings. Reseeding should be delayed for at least 90 - 120 days following application of Weed Impede. With reseeding, it is essential that proper cultural practices such as soil cultivation and seedbed preparation, irrigation and fertilization be followed. For satisfactory reseeding results following use of Weed Impede, the seeding rate should be increased and equipment designed to play seed in full contact with soil (such as the Rogers Aero Seeder) should be employed.

The Monterey Weed Impede (Surflan Herbicide) is not labeled for nutsedge or nutgrass control. It does kill a large variety of other broadleaf weeds and is safe for many lawn types, but it would most likely not work for your needs. Nutsedge is a weed that requires a very specific treatment with products specificially targeted to that weed and not many others. Our Sedgehammer Herbicide is one of the best products on the market for control of Nutsedge.

We do not recommend applying Monterey Weed Impede (Surflan Herbicide) with a hose end sprayer.

The Weed Impede product label does recommend that you use either a handheld sprayer or a backpack sprayer to get even coverage and this would be our recommendation as well. The amount of Weed Impede you will use will vary depending on what weeds you are trying to prevent and what season you are treating in but in general you will need 1-12 fl oz per 1,000 sq ft of area to be treated. According to the Weed Impede product label:

"The amount of water used to apply WEED IMPEDE™ herbicide is not critical, but should be sufficient for uniform coverage of the target area. Calibrate by determining the volume of water required to treat 1,000 square feet. Use this calibration volume to determine the amount of water and WEED IMPEDE™ herbicide needed to treat the target area (see the following calibration example). Note: Sprayer calibration (volume of spray needed to treat 1,000 square feet) will vary with each individual operator.
Steps in Calibration:
1. Mark an area of 1,000 square feet (i.e. 20 by 50 feet or 25 by 40 feet).
2. Place the sprayer on a level surface and add water noting the final level of water in the spray tank.
3. Spray the marked area with a sufficient volume of water to provide uniform coverage. Refill the sprayer to the same level as before measuring the amount of water added. The measured water added to the sprayer is the volume needed to cover 1,000 square feet.
4. Determine the application rate (fl. oz./1,000 sq. ft.) for WEED IMPEDE™ from the Recommendations section of this label.
5. To each volume of water used as measured in step 3, add the amount of WEED IMPEDE™ as determined in step 4.
Example: If the sprayer uses 2 gallons of water to cover 1,000 square feet and the desired application rate of WEED IMPEDE™ is 3 fluid oz./1,000 square feet, then you would add 3 fluid ounces of WEED IMPEDE™ to every 2 gallons of water to be used."

 

Weed Impede can only be used on plants listed on the product label that will not bear fruit for at least one year. Unfortunately raspberries are not listed on the product label of Weed Impede. We recommend you contact your local Dept of Agriculture as they are usually helpful in coming up with a product or a combination of products that can be used on specific crops.

Weed Impede is not specifically labeled for basket grass.  One thing to note is that weed impede is a pre-emergent mainly labeled to keep certain type of turf grasses out of other turf grass and landscaped areas.  Are you looking to kill existing basket grass?  You should use a non-selective weed killer to eradicate basket grass, like our professional Eraser product.  This will kill anything it touches, like Roundup but stronger. So be careful where you apply it.

Application timing of Monterey Weed Impede will vary by region and the exact weeds you are targeting. We recommend contacting your local extension office to confirm the right application timing for your needs. 

 

Per the Monterey Weed Impede product label:  “Do not spray in an area that will be planted or seeded for 6 months after application when applying at the 3 fl. oz. per 1,000 sq. ft. use rate.  Do not spray in an area that will be planted or seeded for 12 months after application when applying at the 5.75 fl. oz. per 1,000 sq. ft. use rate.”

Monterey Weed Impede is a pre-emergent treatment for control of annual grasses and certain broadleaf weeds in established warm-season turf. This product will not work to kill any existing spurge. To control existing or actively growing spurge you can look at a product like Monterey Spurge Power. 

Yes, Monterey Weed Impede (Surflan Herbicide) is labeled to treat spurge in ryegrass. You will 1.5 - 3 oz. per 1,000 sq. ft. Please see the Label for complete application instructions 

Yes, Monterey Weed Impede (Surflan Herbicide) will help prevent the johnsongrass seeds from germinating 

No, Monterey Weed Impede is used for pre-emergent control of broadleaf weeds and would not kill any weeds that are currently growing. Without knowing what type of lawn you have, the only product we could recommend would be Solitare which is labeled for Warm and Cool Season lawns. Please check product label for your lawn type and application instructions before using.

Only time is going to tell if there is any effects from an over applciation of Monterey Weed Impede (Surflan Herbicide).  The only thing that can usually be done when an herbicide is over applied is applying an activated charcoal (liquid carbon) immediately after doing so.  You may have to delay seeding for at least 8 months from when you applied as it can last up to that time at a high rate and would not be able to apply again for at least one year.