The phrase "ear to the ground" is commonly used to describe someone who is vigilant and alert about the surrounding environment, always on the lookout for any potential danger or opportunity. If you're looking for alternative terms to convey the same meaning, consider similar idiomatic expressions like "keeping your eyes peeled," "on high alert," and "being watchful." Other related phrases include "keeping a close eye on," "attentive," and "wary." Whatever term you choose, remember that staying alert and attuned to your surroundings can help you make better decisions and stay safe in a wide range of situations.