What is the best treatment method for established perennials?

The best treatment method for established perennials is the use of translocated herbicides during root food movement. This approach is effective because it targets the plant's physiological processes. Translocated herbicides work by being absorbed into the plant and moving through its vascular system, ultimately reaching the roots. This method is particularly beneficial for perennial plants because they often have deep root systems that enable them to recover from stress. By applying translocated herbicides when the plant is actively transporting nutrients to its roots—typically in late summer or early fall—you ensure maximum effectiveness, as the herbicide can disrupt the plant's ability to thrive and reproduce.

In contrast, a surface application of granular herbicides may not penetrate the dense foliage or root structure of established perennials effectively, thus offering limited control. Regular mowing can manage the top growth, but it does not address the root system, allowing the plants to regrow rapidly. Manual pulling may be effective in some situations but is labor-intensive and often impractical for large infestations or well-established plants with extensive root systems. Therefore, utilizing translocated herbicides at the right time is the most effective strategy for controlling established perennials.