When is conservation tillage consistently recommended?

Conservation tillage is typically recommended for slopes less than 18% because this practice helps reduce soil erosion and maintain soil structure, especially on steeper terrains. When the slope is greater than 18%, the risk of erosion increases significantly, which can undermine the benefits of conservation tillage. This method is designed to leave residue on the soil surface to protect it from water and wind erosion and improve soil health.

Therefore, recommending conservation tillage for areas with slopes less than 18% ensures that the benefits of this practice can be maximized while minimizing the risk of soil loss. The other choices suggest greater slope percentages, which could compromise the effectiveness of conservation tillage due to increased erosion risks, making them less appropriate.