Impact of Frequently Employed Herbicides in Suppressing Woody Plants within Forest Gardens
In the realm of forest management, herbicides play a significant role in selectively removing less desirable trees, shrubs, and vines to improve forest health and growth. This article provides a comprehensive guide to the use of herbicides, based on a fact sheet first published in July, 2006.
The guide, rooted in references from Anderson and McGlamery (1992) and Arnold and LaBarge (1994), presents two tables detailing the relative effectiveness of several commonly used herbicides in controlling specific woody species.
When choosing an herbicide, factors such as ease of use, availability, worker exposure, environmental safety, personal experience, and effectiveness in controlling the target plant species are crucial considerations. It is essential to adhere to label directions for the careful and proper application of herbicides, as this minimizes personal and environmental risks while maximizing herbicide effectiveness.
The effectiveness of herbicides can vary based on factors such as the health and vigor of the plant, the amount and concentration of herbicide used, the method and season of application, and so on.
Table 1 offers a guide to the relative effectiveness of herbicides when frilling, girdling, or injecting, and also for the effectiveness of water-soluble herbicides in preventing sprouting when applied to a stump immediately after cutting. Herbicides based on glyphosate and triclopyr are generally more effective when applied via frilling, girdling, or injecting treatments on certain tree species. Notably, triclopyr shows strong relative efficacy on broadleaf trees, while glyphosate is effective on a wider range of species. The choice between application methods impacts uptake and overall effectiveness, with injection often providing more direct and lasting control than frilling or girdling.
Table 2 is a guide to the relative effectiveness of oil-soluble herbicides when applied as basal sprays or as cut stump treatments to prevent sprouting. Here, a ranking of Susceptible (S) indicates that a particular species is usually susceptible to the herbicide, and little if any retreatment should be necessary. A ranking of Intermediate (I) means that while not usually as effective as an herbicide ranked S, the herbicide will kill a high proportion of the treated stems. Conversely, a ranking of Resistant (R) means that the herbicide will usually provide relatively poor control of that particular species. When an herbicide that is ranked I is used, a portion of the stems may require retreatment.
It is important to note that no estimate is provided in the table when there is not enough information or experience to provide a reasonable estimate of control. Deadening, often chosen when removal is not economically feasible, is a common method for controlling unwanted plant growth in forests.
In conclusion, this guide serves as a valuable resource for those involved in forest management, offering insights into the selection, application, and effectiveness of various herbicides in controlling specific woody species. By adhering to label directions and considering the factors outlined in this guide, forest managers can make informed decisions that promote the health and growth of their forests.
