Cal. Gov. Code § 39562.1
At the time it adopts the resolution as provided for by Sections 39561 and 39562, the legislative body may also find and declare that weeds on specified parcels of property are seasonal and recurrent nuisances.
Such seasonal and recurrent nuisances shall be abated in accordance with the provisions of this article, provided, that upon the second and any subsequent occurrence of such nuisance on the same parcel or parcels within the same calendar year, no further hearings need be held and it shall be sufficient to mail a post card notice to the owners of the property as they and their addresses appear upon the current assessment roll.
The notice shall refer to and describe the property and shall state that noxious or dangerous weeds of a seasonal and recurrent nature are growing on or in front of the property, and that the same constitute a public nuisance which must be abated by the removal of said noxious or dangerous weeds, and that otherwise they will be removed and the nuisance will be abated by the city authorities, in which case the cost of such removal shall be assessed upon the parcel and lands from which or in front of which such weeds are removed and that upon confirmation such cost will constitute a lien upon such parcel or lands until paid.
Ca. Gov. Code § 39562.1