Clethodim vs. Bermudagrass: Effective Weed Control

Clethodim is a widely used herbicide that specifically targets grasses, making it an essential tool for controlling unwanted grass species in agricultural and turf management settings. However, when it comes to managing Bermudagrass, a tough and perennial grass, many growers and landscapers are left wondering whether Clethodim can effectively control it.

In this article, we will explore how Clethodim works, how it compares to Bermudagrass, and whether it can be used as an effective tool in managing or controlling this resilient grass species.

What is Clethodim?

Clethodim is a selective post-emergent herbicide primarily used to control grass weeds in various crops, including soybeans, corn, cotton, and rice, as well as non-crop areas like lawns and turf. It is part of the cyclohexanedione class of herbicides, and it works by inhibiting the acetyl-CoA carboxylase (ACCase) enzyme, which is essential for the production of fatty acids in plants. Without this enzyme, the plant cannot form the necessary lipids for growth, leading to cell damage and eventual death of the grass.

Clethodim is known for being grass-selective, meaning it primarily targets grass species while leaving broadleaf plants mostly unaffected, making it an effective tool for managing grass weeds in crop fields and turf areas.

How Does Clethodim Work on Bermudagrass?

Bermudagrass is a perennial and hardy grass species known for its extensive root system and drought tolerance, often making it a challenge to control in certain situations. It is widely used in lawns, golf courses, and pastures, but its aggressive growth can become problematic in agricultural fields or when it invades other areas.

When Clethodim is applied to Bermudagrass, it works in the same way it does with other grasses. The herbicide inhibits the acetyl-CoA carboxylase enzyme in Bermudagrass, leading to disruption in fatty acid synthesis. This causes the plant to experience growth cessation, yellowing, and eventual death of the grass. However, due to the resilience and deep root system of Bermudagrass, it may require multiple applications or higher doses of Clethodim to effectively control it.

While Clethodim can be effective on Bermudagrass, it is important to understand that Bermudagrass can be somewhat resistant to herbicides, and the process of killing it may take some time. To ensure optimal results, timing, dosage, and environmental conditions must be carefully considered.

Effectiveness of Clethodim on Bermudagrass: Key Factors

1. Timing of Application:

   • Clethodim works best when applied to actively growing Bermudagrass. It is most effective during the early stages of growth before the plant has fully established itself and developed a robust root system.
   • Applying Clethodim during Bermudagrass dormancy or when the grass is stressed (due to drought or extreme temperatures) will significantly reduce the herbicide’s effectiveness.

2. Multiple Applications:

   • Due to the hardiness of Bermudagrass, Clethodim may need to be applied multiple times to achieve complete control. A two- to three-application program is often recommended, spaced several weeks apart to ensure the herbicide targets both the new growth and the regrowth of the grass.

3. Application Rate:

   • The recommended application rate of Clethodim for controlling Bermudagrass is typically 0.1 to 0.2 pounds per acre, depending on the specific formulation. Higher rates may be necessary in cases of heavy infestation or older Bermudagrass plants. Always follow the label recommendations for the specific product you are using.

4. Environmental Conditions:

   • Clethodim works best under moderate weather conditions. Extremely high temperatures or heavy rainfall can affect its performance. It is recommended to apply Clethodim during mild temperatures (preferably between 60°F and 85°F) for optimal results.

Clethodim vs. Bermudagrass: Pros and Cons

Pros of Using Clethodim on Bermudagrass:

• Selective control: Clethodim targets grasses, leaving most broadleaf plants unaffected. This makes it an ideal option when trying to control Bermudagrass in crop fields or other areas with desirable broadleaf plants.
• Effective for initial control: When used early in the growing season, Clethodim can significantly reduce the population of Bermudagrass and provide effective weed control for multiple weeks.
• Reduced competition for crops: In agricultural settings, controlling Bermudagrass can reduce weed competition, allowing crops to thrive and improving yields.

Cons of Using Clethodim on Bermudagrass:

• Resistant species: Bermudagrass can sometimes show resistance to Clethodim, especially if the grass has been exposed to the herbicide repeatedly or if the plant is in its dormant phase.
• Multiple applications required: Since Bermudagrass is tough and has a well-established root system, multiple applications of Clethodim may be needed to completely control it.
• Environmental restrictions: Clethodim should not be applied in areas prone to runoff or near water sources, as it can have detrimental effects on aquatic life.

Best Practices for Using Clethodim to Control Bermudagrass

1. Monitor Growth Stages: Apply Clethodim when Bermudagrass is actively growing, ideally in the spring or early summer, when the grass is young and tender. Avoid applying the herbicide when the plant is dormant.

2. Use in Rotation: To prevent the development of resistance, consider using Clethodim in rotation with other herbicides that target grasses, such as Fusilade or Poast. This will help manage weed populations more effectively.

3. Follow Label Instructions: Always adhere to the label recommendations for both dosage and application timing. This ensures the safety of surrounding plants and optimal effectiveness for weed control.

Conclusion

Clethodim can be an effective solution for managing Bermudagrass, particularly in agricultural settings where this persistent grass competes with crops. However, due to its resilience, Bermudagrass may require multiple applications of Clethodim, proper timing, and attention to dosage for full control. While Clethodim provides targeted control with minimal effect on broadleaf plants, it is important to integrate it into a comprehensive weed management plan that accounts for possible resistance and environmental factors.

By following best practices and utilizing Clethodim in combination with other herbicides, you can effectively manage Bermudagrass and ensure the success of your crop or turf management goals.

Frequently Asked Questions (FAQs)

1. Can Clethodim be used to control all grass species?

   • Clethodim is effective against many grass weeds, but some grasses, including Bermudagrass, can be more resistant to the herbicide, requiring multiple applications for effective control.

2. How long does it take for Clethodim to kill Bermudagrass?

   • After application, Clethodim typically begins to show signs of weed damage within 24-48 hours, but full control may take several weeks depending on the severity of the infestation.

3. Is Clethodim safe for crops?

   • Yes, Clethodim is a selective herbicide that primarily targets grasses and leaves most broadleaf crops unharmed when applied correctly.

4. How often should I apply Clethodim to control Bermudagrass?

   • Multiple applications of Clethodim may be necessary to control Bermudagrass, typically spaced 2-4 weeks apart during the growing season.

5. Can I use Clethodim near water sources?

   • No, Clethodim should not be applied near water sources, as it can affect aquatic organisms. Always follow the label guidelines for application and environmental safety.