I helped my Daddy fight a loosing Mole war in his yard for years .
We were at the Hardware store trying to find a poison or trap that might work better than the stuff we had been trying . So we asked ... what works best ?
The owner of the store , I know this sounds crazy but we have these electronic stakes , you drive into the ground and the moles hear the constant noise / vibration , they don't like it and move ... I swear . He said that since Dad was such a long time good customer ... if they didn't work , he would refund his money !
We followed the instructions and slowly , one by one the moles left .
He only got 4 stakes and just moved them around , after a while they all eventually went away . The traps and Poisons we were using always bothered Dad , he didn't want a child or dog/cat getting hurt ... but the electronic repellers ...they were safe .
His took a battery but now some have Solar Cells for power .
the name was Pest Guru ... strange but they did the job .
Dad kept the repellers just in case !
If the things made any noise ... neither me nor Dad could hear it ... it must be low .
Gary