Is Glyphosate Effective for Goosegrass?

If you are a gardener, farmer, or anyone struggling with goosegrass (Eleusine indica)—a tenacious, bushy weed that can invade lawns, farmland, and landscapes—you might wonder if glyphosate (one of the world’s most widely used herbicides) can effectively control it.      

In short, the answer is yes, glyphosate can kill goosegrass, but its effectiveness depends on three key factors: application timing, proper use, and addressing potential weed resistance issues.

Why Glyphosate Works on Goosegrass (And Its Limitations)

Glyphosate is a non-selective herbicide, meaning that the leaves of weeds absorb it, and it is then transported to all parts of the plant—including the roots and stems—to inhibit protein synthesis. This “whole-plant kill” is crucial for goosegrass because its extensive root system allows it to regenerate even if only the above-ground parts are removed. However, the herbicidal effect of glyphosate is not absolutely guaranteed. Two main limitations should be noted:

– Goosegrass Resistance: In some areas (especially those with repeated glyphosate use), goosegrass has developed resistance to this herbicide. Even when the herbicide is applied correctly, resistant plants may not show any signs of damage.

– Growth stage sensitivity: Glyphosate is most effective on young, vigorous goosegrass plants. Mature plants with thick stems or that have produced seeds are more difficult to kill because their outer layers hinder herbicide absorption.

How to Use Glyphosate for Goosegrass: Step-by-Step Guide

To maximise the control effect of glyphosate on goosegrass, please follow these practical steps

1. Reading the Product Label

The product label on glyphosate containers is a wealth of information, and it is of utmost importance to read and follow it meticulously. Different formulations of glyphosate, such as the 41% glyphosate IPA salt SL, come with their own specific dilution ratios and safety instructions. For example, some labels may indicate that for a particular application, the glyphosate should be diluted with a specific amount of water per gallon, and this ratio is crucial for achieving the right concentration. If the dilution is incorrect, it can have a significant impact on the herbicide’s effectiveness. Diluting it too much may result in a weak solution that is unable to penetrate the goosegrass effectively, leading to only partial damage to the leaves and leaving the roots intact. On the other hand, using a solution that is too concentrated can not only be wasteful but may also cause damage to the surrounding environment and non-target plants. Additionally, the safety instructions on the label are vital for protecting the user. They may include information on the type of protective gear to wear, such as gloves, long sleeves, pants, and safety glasses, as well as precautions to take during mixing and application to avoid any potential health risks.​

2.Timing is Everything​

The timing of glyphosate application is a critical factor in determining its success against goosegrass. The ideal stage to target goosegrass is when it is 2 – 6 inches tall, which corresponds to the young seedling to early tillering stage. At this early growth stage, the goosegrass is more vulnerable to the effects of glyphosate. The plant’s cells are actively dividing, and its physiological processes are in high gear. The young leaves are tender and have a thinner cuticle, which allows the glyphosate to be absorbed more easily. Once absorbed, the herbicide can quickly move through the plant’s vascular system due to the plant’s rapid growth and active circulation, reaching all parts of the plant, including the roots, to effectively kill it.

​

However, applying glyphosate during extreme weather conditions, such as extreme heat (above 90°F/32°C) or drought, can be counterproductive. In extreme heat, the goosegrass may close its stomata, which are the tiny pores on the leaves through which gases and water vapor are exchanged. When the stomata are closed, the absorption of glyphosate is severely hindered as the herbicide cannot enter the plant effectively. During a drought, the stressed goosegrass may have reduced metabolic activity. It may also have a thicker cuticle as a protective mechanism to conserve water. These factors make it more difficult for glyphosate to be absorbed and translocated within the plant, resulting in decreased effectiveness of the herbicide. Early morning or late afternoon, when temperatures are milder, is the best time to apply glyphosate. At these times, the goosegrass is more likely to have its stomata open, allowing for better absorption of the herbicide, and the environmental conditions are more conducive to the proper functioning of the glyphosate.​

3.Solution Preparation and Application​

Preparing the glyphosate solution correctly is essential for its effectiveness. For concentrate formulations, the mixing process must be carried out with precision. As a general guideline, for goosegrass control, one typically mixes 2 – 4 ounces of 41% glyphosate per gallon of water, as recommended on the label. It is crucial to use clean water for mixing. Impurities in the water, such as dirt, minerals, or other contaminants, can interfere with the chemical properties of the glyphosate and reduce its effectiveness. The mixing should be done thoroughly to ensure that the glyphosate is evenly distributed in the water, creating a homogeneous solution.​

When it comes to application, a sprayer is commonly used to coat all the above-ground parts of the goosegrass, including the leaves and stems. The goal is to achieve uniform coverage. This means that every part of the goosegrass should receive an adequate amount of the glyphosate solution. Missed spots can provide an opportunity for the goosegrass to regrow. To ensure uniform coverage, the sprayer should be held at the right distance from the plant and moved in a consistent, sweeping motion. It is also important to adjust the sprayer settings, such as the nozzle type and pressure, according to the specific requirements of the application. For example, a fine-mist nozzle may be more suitable for smaller, more delicate goosegrass plants, while a coarser spray may be better for larger, more robust ones.​

4.The Role of Adjuvants​

Adjuvants, such as nonionic surfactants, can play a significant role in enhancing the effectiveness of glyphosate, especially when dealing with mature or hard – to – kill goosegrass. These substances work by reducing the surface tension of the glyphosate solution. The waxy leaves of goosegrass can be a challenge for the herbicide to adhere to and penetrate. A nonionic surfactant helps the glyphosate solution spread more evenly across the waxy surface of the leaves, increasing the contact area between the herbicide and the plant. This improved spreading also allows the glyphosate to better penetrate the leaf cuticle and enter the plant cells. By enhancing the absorption of glyphosate, adjuvants can boost the herbicide’s effectiveness by 20 – 30%.

​

There are numerous real-world examples of the successful use of adjuvants. In some large-scale agricultural fields where mature goosegrass had been a persistent problem, farmers added a nonionic surfactant to their glyphosate solution. The results were remarkable. The previously hard – to – control goosegrass was effectively killed, with a much higher rate of success compared to when glyphosate was used alone. In a home garden setting, a gardener struggling to get rid of large, established goosegrass patches found that by adding an adjuvant to the glyphosate, the weed began to show signs of wilting and dying within a few days, while in previous attempts without the adjuvant, the goosegrass had continued to thrive despite glyphosate application. These examples clearly demonstrate the importance and effectiveness of using adjuvants in glyphosate applications for goosegrass control.

Key Safety & Best Practices About Glyphosate

Glyphosate is safe when used properly, but it requires careful handling to protect yourself, other plants, and the environment:

-Wear protective gear: Always put on gloves, long sleeves, pants, and safety glasses when mixing. Avoid water sources: Do not apply near ponds, streams, or wells — glyphosate can leach into water if overused.

-Some alternative herbicides still work for some resistant populations. These include paraquat, glufosinate, and certain residual or pre-emergence options. Their success depends on careful management.

-Wait for results: Glyphosate takes 7–14 days to kill goosegrass. Do not reapply sooner — give the glyphosate time to work through the plant’s system.

Final Thoughts

Glyphosate is a reliable tool for controlling goosegrass, but it’s not a “set-it-and-forget-it” solution. By applying it at the right stage, using the correct rate, and following safety guidelines, you can eliminate this stubborn weed and keep your spaces weed-free. Efficacy drops fast for larger or resistant plants. Based on my experience, you need integrated, multi-herbicide approaches. I suggest mixing modes of action. If you’re unsure about choosing a glyphosate formulation or how to deal with resistant goosegrass, please feel free to consult us at any time for technical support.