Which property of a herbicide provides selective control, sparing desirable turf?

Which property of a herbicide provides selective control, sparing desirable turf?

• A. Broad spectrum.
• B. Selective.
• C. Soil residual.
• D. Narrow spectrum.

Answer: (B)

The core idea being tested is selectivity—the ability of a herbicide to control certain plants while leaving the desirable turf unharmed. A selective herbicide targets biochemical pathways or uptake patterns that are different between weeds and turfgrass, so it disrupts weed growth without damaging the grass. For example, many selective products act on a weed-specific hormone system or on enzymes that are present in broadleaf weeds but not in turfgrass, or they’re taken up and translocated more by the weeds. This is why the best choice is descriptive of that property: it describes a product that provides control in a way that spares the turf. Broad-spectrum would affect a wide range of plants and could injure the turf; soil residual describes how long the chemical stays active in the soil rather than its selectivity; narrow spectrum refers to targeting a limited set of weeds, which doesn’t inherently guarantee turf safety.

The core idea being tested is selectivity—the ability of a herbicide to control certain plants while leaving the desirable turf unharmed. A selective herbicide targets biochemical pathways or uptake patterns that are different between weeds and turfgrass, so it disrupts weed growth without damaging the grass. For example, many selective products act on a weed-specific hormone system or on enzymes that are present in broadleaf weeds but not in turfgrass, or they’re taken up and translocated more by the weeds.

This is why the best choice is descriptive of that property: it describes a product that provides control in a way that spares the turf. Broad-spectrum would affect a wide range of plants and could injure the turf; soil residual describes how long the chemical stays active in the soil rather than its selectivity; narrow spectrum refers to targeting a limited set of weeds, which doesn’t inherently guarantee turf safety.