Barnyardgrass Control: How to Get Rid of Barnyardgrass

Barnyardgrass (Echinochloa crus-gallia) is a summer annual grassy weed which has long been a problem on agricultural farms but has now spread its way onto residential lawns. It is often found in rice, corn, orchards, vegetables and other agricultural crops. It can also be found in moist turf areas and marshes.

This weed is easy to identify because of its unique seedhead, which is usually purple with a bristle at the end which can vary from 2 to 8 inches in length. Seeds develop on side branches and are flat on one side and round on the other.

This weed can produce more than 2,400 pounds of seeds per acre. Wind, water, animals, and humans help to spread the seed to other areas. Barnyardgrass is a vigorous grower and quickly removes vital nutrients such as potassium, nitrogen and phosphorus from the soil so if it grows onto your lawn, you have to act fast to control it before it zaps the lawn of all of its nutrition.

If your lawn has been invaded by barnyardgrass, our step-by-step DIY treatment guide will show you exactly how to get rid of barnyardgrass quickly and affordably.

Identification

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

• Barnyardgrasses grow in clumps, growing 1 to 5 feet in height at maturity. The grass blades are mostly flat, with the upward-facing surfaces being hairless.
• The grass blades are up to 8 inches in length and three-quarter inches in width. These weeds are most identifiable when flowering or when their seedheads have formed.
• The plant's inflorescence, or flowering structure, is a green-to-purple, lumpy, panicle. The seeds, when released, look like light-brown teardrop shapes.

Use the description and image above to help you to identify whether your weed is barnyardgrass. If you are unsure which kind of weed you are encountering in your yard, turn to the experts to ID the weed for you by contacting us.

Inspection

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

Where to Inspect

Barnyard grasses grow in moist, poorly drained areas where the soil has been disturbed.

Common sites include crops, fields, waste lands, ditches, marshes, roadsides, marshes, wet meadows, pastures, floodplains, lakeshores, gardens, new turf establishments, and poorly maintained lawns.  

What to Look For

Watch out for an erect or slightly sagging stalk growing at the tops of the plants. Aside from checking the severity of its presence, also check what maturity level the barnyardgrass is at because if they are more mature, you're looking at a more difficult time removing the plant.

Treatment

Barnyardgrass can be a headache to hand-pull and frankly doing so is a waste of time because if it has already gone to seed, it will just grow back if you yank it out from the ground.

The best option for control is utilizing chemical herbicides. Make sure to wear the proper personal protective equipment before applying any herbicides to your yard.

We recommend using a non-selective herbicide like Eraser 41% Glyphosphate which contains the active ingredient glyphosate to kill barnyardgrass in your turf. Keep in mind this product is non-selective meaning it will kill all foliage it comes into contact with. 

Step 1: Spot Treat With Post Emergent Herbicide

Determine how much Eraser 41% Glyphosphate to use by measuring the square footage of the treatment area. To do this, measure the length and width of the treatment area in feet then multiply them together (length X width = square footage). 

For spot treatments, use 2 1/2 oz. (5 tbs) of Eraser 41% Glyphosate in a gallon of water to treat 300 sq. ft.

Mix the appropriate amount of Eraser 41% Glyphosate into your sprayer and mix well. You can do this by filling the tank with half the amount of water, adding in the correct amount of product, then filling the rest of the way with remaining half of water. Agitate the tank to thoroughly mix it in. 

With a fan tip nozzle, spray a fine mist to the barnyardgrass to ensure it is evenly coated. To better protect desired foliage you can place a cardboard box between the weed and desired foliage to prevent drift. 

Step 2: Reapply if Needed

Most treated weeds usually show initial symptoms in 2-4 days and complete kill in 1-2 weeks.

If barnyardgrass is still occuring then you can make a second application when 4 weeks have passed after the first application. 

It’s best to apply on a warm sunny day when daytime temperatures are above 60 degrees Fahrenheit. Weed control is accelerated by warm sunny weather. 

Prevention

After you have eliminated barnyardgrass from your property, you need to implement culture practices as shown below:

• Prevent barnyardgrass from returning to your lawn with Barricade Pre-Emergent Herbicide Prodiamine Granular. This product contains prodiamine, a highly effective active ingredient that controls and prevents seeds from sprouting. Depending on your turfgrass type, Barricade can be applied at a rate from 1.5 pounds to 4 pounds per 1,000 sq. ft. Calibrate your spreader to the right spreader setting for application and load the appropriate amount of granules into a push or broadcast spreader. Apply the granules until your lawn is covered evenly to get a uniform application. After broadcasting the granules, you should then water in and activate them with at least 0.5 inches of water.
• Mow your grass at proper intervals to maintain a thick growing density. A lawn dense with taller trimmed grass is better able to choke out weeds and prevent them from establishing.
• Reduce the shade cast on your lawn by trimming overgrown shrubbery and tree branches, rake away leaf litter and pick up any debris, and employ a proper watering schedule to provide the local grass with enough water to strengthen its roots, but not so much that will encourage weeds. Many grasses require 1 inch of water every week. Apply the water all at once in the morning so it has time to seep into the ground without evaporating in the sun.

Key Takeaways

What is Barnyardgrass?

• Barnyardgrass is a particularly difficult summer weed to control because it has multiple germinations or cohorts. It is a fast grower that is known to spread over lawns and gardens quickly

How to Get Rid of Barnyardgrass

• We recommend applying a spot treatment of Eraser 41% Glyphosate to remove Barnyardgrass from your lawn.

Preventing Barnyardgrass Reinfestations

• To prevent barnyardgrass from returning, a mixture of good lawn maintenance practices and repeat pre-emergent applications of Barricade Pre-Emergent Herbicide Prodiamine Granular should be implemented.