Glyphosate: The Effective Solution for Killing Mature Pine Trees
Glyphosate, a systemic herbicide, has proven to be an effective solution for killing mature pine trees. This comprehensive guide will delve into the effectiveness of glyphosate, the chemicals that can prevent bark beetle attacks, and the precise amount of glyphosate required to harm a pine tree.
How Effective is Glyphosate in Killing Mature Pine Trees?
Glyphosate is a powerful herbicide that can effectively kill pine trees, even mature ones. Studies have shown that glyphosate can injure young pine seedlings and reduce their height growth, even at low application rates. For example, a study by Haywood and Melder (1990) found that broadcasting glyphosate over loblolly pine seedlings at rates of 0.42 to 1.68 kg acid equivalent per hectare resulted in injury and reduced height growth, with many treatments increasing pine mortality.
When it comes to mature pine trees, a more targeted approach is often necessary. One effective method is to drill holes into the tree and inject undiluted glyphosate concentrate directly into the tree. This technique has been demonstrated in a YouTube video, where one ounce of undiluted 41% glyphosate concentrate was used to kill a 70-foot diseased pine tree. The video shows the tree’s decline over several weeks, with visible effects such as brown needles appearing within a month.
What Chemicals Can Prevent Bark Beetle Attacks on Pine Trees?
Bark beetles are a significant threat to pine trees, and several chemicals can be used to prevent these attacks. One common method is to apply insecticides that target the beetles. Permethrin and bifenthrin are commonly used to control bark beetles and can be applied as foliar sprays or soil injections, typically at rates of 0.5 to 2.0 ounces per 100 gallons of water.
Another approach is to use systemic insecticides that are absorbed by the tree and distributed throughout its tissues. Imidacloprid is an example of such an insecticide, which can be applied as a soil injection or foliar spray. Research has shown that imidacloprid can effectively control bark beetles and reduce tree mortality.
How Much Glyphosate is Needed to Harm a Pine Tree?
The amount of glyphosate required to harm a pine tree depends on several factors, including the tree’s size, age, and health. Generally, a higher dose of glyphosate is needed to kill a mature pine tree compared to a young seedling.
For foliar sprays, a typical rate is 1 to 2% glyphosate solution, which translates to 1 to 2 ounces of glyphosate per gallon of water. For soil applications, the rate can be higher, typically 2 to 4 ounces of glyphosate per gallon of water.
When using the drilling method, as demonstrated in the YouTube video, a smaller amount of undiluted glyphosate concentrate can be effective. In this case, one ounce of 41% glyphosate concentrate was sufficient to kill a 70-foot pine tree.
Safety Precautions
When working with glyphosate or other herbicides, it is essential to follow safety precautions to avoid exposure and environmental contamination. These precautions include:
- Wearing protective clothing, including gloves, long sleeves, and eye protection.
- Avoiding overspray or drift onto non-target plants.
- Following the recommended application rates and methods.
- Avoiding application during windy or rainy conditions.
- Keeping the herbicide away from water sources and wildlife.
Reference:
- Haywood, J. D., & Melder, T. E. (1990). Loblolly pine seedling response to herbaceous weed control. Southern Journal of Applied Forestry, 14(2), 73-77.
- Use Glyphosate with Care Near Trees: https://extension.psu.edu/use-glyphosate-with-care-near-trees
- Glyphosate on Trees: https://www.thecombineforum.com/threads/glyphosate-on-trees.30137/
- Glyphosate and Pine Trees: https://www.tractorbynet.com/forums/threads/spraying-glyphosate-and-pine-trees.319271/