Conifers are resistant to which group of grass-control chemicals?

Conifers are resistant to which group of grass-control chemicals?

• A. Triazines—simazine, atrazine, and hexazinone
• B. Glyphosate
• C. Sulfometuron
• D. Imazapyr

Answer: (A)

Conifers have a notable tolerance to a group of herbicides known as triazines, which include simazine, atrazine, and hexazinone. These compounds inhibit photosystem II, effectively stopping photosynthesis in many plants. Grasses and many broadleaf weeds readily take up and are damaged by triazines, but conifers tend to withstand these chemicals, so they remain unharmed when triazines are used at labeled rates around a stand. That compatibility is why this group is identified as the one conifers resist. In contrast, other options like glyphosate, sulfometuron, and imazapyr are more likely to injure conifers if they contact the foliage or are taken up, so they’re not the group conifers are resistant to.

Conifers have a notable tolerance to a group of herbicides known as triazines, which include simazine, atrazine, and hexazinone. These compounds inhibit photosystem II, effectively stopping photosynthesis in many plants. Grasses and many broadleaf weeds readily take up and are damaged by triazines, but conifers tend to withstand these chemicals, so they remain unharmed when triazines are used at labeled rates around a stand. That compatibility is why this group is identified as the one conifers resist. In contrast, other options like glyphosate, sulfometuron, and imazapyr are more likely to injure conifers if they contact the foliage or are taken up, so they’re not the group conifers are resistant to.