Devices and method for the extermination of pests are described. These devices and methods may be used to inject gases, which may be inert gases, underground to inject the gas into burrows of pests. In one embodiment, the device is an earth penetrator with hole for injecting gas through discharge holes at the distal end. The discharge holes maybe covered during penetration to prevent dirt from entering into the device. A device for covering and uncovering the hole are provided. The device includes a valve to controllably deliver the gas to the discharge ports. The method includes covering the discharge ports, inserting the device into the ground, uncovering the discharge ports, and then injecting the gas.
