Witchgrass Control: How To Get Rid of Witchgrass

This page is a general DIY guide for controlling witchgrass. Using the recommended products and methods, you can control witchgrass. Follow this DIY article and use the recommended products; we guarantee 100% control of witchgrass.

Witchgrass, also known as panicgrass, ticklegrass, tumble panic, tumbleweed grass, witches hair, common panic grass, old witch grass, and fool hay, is a common summer annual grass weed. This problematic weed gets its name due to its appearance: the hairy stem and large puffy seed head resemble the features of a storybook witch.

Compared to other weeds, witchgrass is a poor competitor in areas with existing vegetation but can still make its way through if needed. Once established, this weed can cause people to become allergic to it and cause toxic levels of nitrate if the soil is fertile. 

If you notice a witchgrass problem on your lawn, the following guide can help. Our lawn care experts have put together this DIY guide to show you precisely what needs to be done to remove Witchgrass from your lawn using our professional herbicide recommendations. Follow the step-by-step instructions below, and you will be guaranteed to eliminate Witchgrass fast and at an affordable price.

Identification

Before proceeding with a treatment program, you must be certain that you are dealing with a witchgrass infestation. Careless identification can lead to using the wrong treatment methods, which can be a waste of time and money. Below are the following characteristics to help you understand what witchgrass looks like.

• Witchgrass is a warm-seasoned annual grassy weed that reaches about 1-3 feet tall when mature. This erect plant can easily be identified by its sprawling or spreading stems emerging from the same collar, otherwise it is unbranched. 
• In its early stages, witchgrass leaves sheathes, and the collar possesses dense, green hair that becomes reddish purple as the plant matures.
• The leaf blades can grow 4 to 10 inches long and up to three-fifths wide. Each leaf has a distinct, white midrib. They will also roll in the bud and lack any auricles. Often, they appear limp, becoming more ragged as they age. 
• Each stem forms a large open panicle shape, also called spikelets, from the upper portion of the plant. The spikelets from these plants produce a single seed at the tip, which makes it appear fluffy. This spikelet can grow to half the length of the entire weed. The root system of witchgrass is fibrous. 

Use our description and image above to help you to identify witchgrass on your lawn. If you are having trouble identifying the weed, contact us and we will correctly identify the plant for you as well and offer herbicide product recommendations for control.

Inspection

Once you are confirmed that you are dealing with witchgrass, you can move on to inspection. During this phase, you will locate areas where witchgrass is thriving and observe the conditions that allow it to thrive. This information will help you know where to focus your herbicide application.

Where to Inspect

Witchgrass can be found in most soil types, but it grows best in sandy to loamy soils that receive full sunlight throughout the day. It also grows well in areas that receive partial sun. 

This weed grows commonly in croplands, gardens, lawns, landscapes, beaches, ditches, empty lots, railroads, waste areas, and other disturbed areas. 

What To Look For

As mentioned in identification, you'll want to look for grass with a hairy stem and a large puffy seedhead. Witchgrass will be hard to miss on a lawn or landscape because it stands out amongst uniform grass.

Treatment

After identifying witchgrass and inspecting where it is most active in your lawn, you can begin to treat your area. Be sure to wear the appropriate personal protective equipment (PPE) before handling or applying any product.

Post-emergent herbicides containing the active ingredient glyphosate are most effective against witchgrass. Eraser 41% is a non-selective glyphosate-based product that kills all plants that come in contact with it. 

We recommend using a barrier like a cardboard box during applications to avoid spray drift onto desired plants and prevent the death of desired foliage. 

Step 1: Measure and Mix Eraser

Measure the square footage of the treatment area to determine how much Eraser 41% glyphosate to use. To do this, measure the length and width of the treatment area in feet and multiply them together (length X width = square footage). 

For spot treatments, use 2 1/2 oz. of Eraser 41% Glyphosate per gallon of water to treat an area of approximately 300 sq. ft. 

Mix and apply this product with a handheld pump sprayer. Label your sprayer specifically for non-selective herbicides to help prevent cross-contamination in the future. 

To mix, simply pour in half the amount of water, add a measured amount of Eraser 41% Glyphosate, and then add the remaining half of water. Close the tank lid and shake until the solution is mixed. 

Step 2: Spot Treat the Witchgrass

Spot treat the witchgrasses you found during your inspection. Adjust the sprayer nozzle to a fan or cone spray setting, then spray the weed leaves until they are wet but not to the point of runoff. 

It is best to make applications when the weather is warm, sunny, and above 60 degrees Fahrenheit. Plus, weed control is accelerated during warm, sunny weather. 

Most treated weeds show initial symptoms in 2-4 days and complete kill in 1-2 weeks. Hard-to-control weeds that are not completely dead in 4 weeks may require a second application. 

Prevention

Once witchgrass has been eliminated from your property, you will need to implement preventative measures to ensure that it does not return.

• To stop witchgrass from growing on your property, apply a pre-emergent herbicide when soil temperatures reach about 55 degrees Fahrenheit or higher - typically, this is about April to October. Barricade Pre-Emergent Herbicide Prodiamine Granular is a prodiamine-based pre-emergent granule herbicide that prevents various weeds, including witchgrass, from emerging in residential turf. To use Barricade Pre-Emergent Herbicide Prodiamine Granular, apply 1.5 to 4 lbs. of product per 1,000 sq. ft., depending on the turf type. A push or broadcast spreader is preferred if you have a large property to spread the granules on, while a hand spreader is better for more precision and control over where you want to spread the granules. Broadcast the granules evenly across your lawn in two perpendicular passes. After broadcasting the granules, water them with at least 0.5 inches of water to activate them. Make an application in the fall to stop seeds from germinating in spring. An additional application may be made after 6 months for year-round weed prevention.
• For larger treatment areas, a pre-emergent such as Prodiamine 65 WDG would be best for witchgrass prevention. Unlike Barricade, Prodiamine 65 WDG is a water-dispersible granule that can be mixed with water and then applied with a backpack sprayer or spray rig. General applications in turf will use 1.00 lbs of Prodiamine 65 WDG per acre with enough water to provide good even coverage, such as 20 gallons. In smaller applications, use 0.4 oz. of product per 0.5 gallons of water per 1,000 sq. ft. Fill the sprayer with half the amount of water, then add the proper rate of product and pour the remaining half of the water into the tank. Agitate the solution until well mixed. After mixing is complete, you can broadcast your mixed solution. For best results, the soil in the treatment area should be free of clods, weeds, and debris such as leaves and mulch. Perform an over-the-top spray over the treatment area until wet, but not to the point of runoff. After application, water the treated area with 0.5 inches of irrigation or rainfall. This must be done at least 14 days after the previous treatment. 
• A lush and healthy lawn is less prone to invasion by the witchgrass. Witchgrass grass grows best in poor soil and disperses an allelopathic chemical that keeps wanted plants from growing. Properly fertilize your property at the best time recommended for your particular grass.
• Mow your grass regularly and at the right height. Witchgrass thrives on sunlight, so keeping a lush lawn shades out weed seeds, hindering their growth. Reseed thin patches of turf in the lawn as an effective means of witchgrass control. Part of effective witchgrass control includes proper fertilization, so take a soil test to determine which amendments are necessary for thick, healthy turfgrass on your lawn.

Key Takeaways

What is Witchgrass?

• Witchgrass is a prolific grassy weed with a unique puffy seedhead and the ability to spread quickly via seed disbursement by the wind.

How to Get Rid of Witchgrass

• Our top recommendation for treating witchgrass is a post-emergent treatment of Eraser 41% Glyphosate. 

Preventing Witchgrass Reinfestations

• Prevent witchgrass reestablishment by maintaining a good lawn care schedule involving mowing, watering, and fertilizing at optimum times. Be sure to apply Barricade Pre-Emergent Herbicide Prodiamine Granular for residential lawns or Prodiamine 65 WDG for larger treatment areas before witchgrass appears to help prevent them.