Iowa Right-of-Way Herbicide Practice Exam

A herbicide that can control all types of plants is classified as a nonselective herbicide. Nonselective herbicides are designed to kill or inhibit the growth of a wide range of plant species, including both agricultural crops and weeds. This broad-spectrum capability makes them particularly useful for tasks such as clearing areas of vegetation, preparing sites for planting, or managing invasive species. Nonselective herbicides are often used in scenarios where complete vegetation control is desired.

In contrast, a selective herbicide is formulated to target specific plants while leaving others unharmed, making it unsuitable for controlling all types of plants. Residual herbicides refer to those that remain in the soil and continue to affect plant growth over time, functioning differently from nonselective products. Lastly, contact herbicides act by destroying the parts of the plant that come into direct contact with the chemical, rather than affecting the entire plant systemically, which again distinguishes them from nonselective herbicides.