Beware!! of the people that are claiming to kill gophers with carbon monoxide. Carbon monoxide is an odorless, colorless gas which just seeps up through the ground when the hose is inserted underground. Gophers have several holes close to the surface where gas can escape. This does not work to kill underground rodents. Also, these people are not usually licensed by the California Department of Pesticide Regulation (DPR). By law, anyone for hire must have a valid DPR license to treat for pests in California.
Becky’s Creative Landscape & Design has a portable machine which adds a white smoke and a repellant to the carbon monoxide gas, therefore the smoke can be seen and the holes filled as the machine is running. This method is effective in making their runs an undesirable place. The gophers leave the area due to the smell and taste. The repellant is odorless to humans. In addition to the underground repellant we use a granular which is watered in by lawn sprinklers. We have had good results with the repellants and they are safe to use where pets and children play. CDPR license#139176. Check a pest control business for valid license on the CDPR website: https://www.cdpr.ca.gov/docs/license/currlic.htm
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