It could have a small spool of wire to drop to the ground to make contact. This would allow the drone to rest on the wire while charging.
Creating current flows from a field is what induction is, so if you're imagining that you could just generate electricity from a field, well, that's what they're already doing. It doesn't take lowering a probe. You can just use an inductor.
https://makezine.com/article/craft/1000-fluorescent-lights-p...