ear to the ground, have one's

have an/(one's) ear to the ground

To listen for any indication of what is happening or will happen. A: "I'm not sure what's going to happen with this merger, so I have an ear to the ground." B: "Please let me know if you hear anything." I know Kim has her ear to the ground in case word gets out about the promotion.
See also: ear, ground, have
Farlex Dictionary of Idioms.

ear to the ground, have one's

Also, keep one's ear to the ground. Be or remain well informed; be on the watch for new trends and information. For example, She knew she'd succeed as a reporter if she kept her ear to the ground. This graphic expression probably alludes to listening for distant hoofbeats by putting one's ear close to the ground. [Late 1800s]
See also: ear, have
The American Heritage® Dictionary of Idioms by Christine Ammer.
See also:
  • have an ear to the ground
  • have an/(one's) ear to the ground
  • keep/have an/your ear to the ground
  • have an/(one's) ear close to the ground
  • keep an ear to the ground
  • keep an/(one's) ear to the ground
  • keep your ear to the ground
  • keep an/(one's) ear close to the ground
  • What’s the deal?
  • what's the deal