When is a broad spectrum, non-selective herbicide appropriate to use on turf?

A broad spectrum, non-selective herbicide is appropriate to use on turf when the existing grass is essentially dominated by weeds or when preparing for new sod installation. This type of herbicide kills all vegetation that it contacts, which makes it suitable in situations where you want to eliminate all existing plant life in the area to start fresh.

When the turf is overrun with weeds, applying a non-selective herbicide allows for the removal of undesired plants and provides a clean slate for new grass to be sodded or seeded. In the context of preparing for new sod, it is vital to clear away all existing vegetation to ensure that the new sod can establish itself without competition for nutrients, water, and sunlight from weeds.

Using this herbicide when the grass is healthy, thriving, or well-established and disease-free would be inappropriate, as it would destroy the desirable grass along with the weeds, leading to further issues in maintaining a healthy turf.