Here's some info from the City of Temecula about their Local Weed Abatement Program for Fire Prevention Program:
The City of Temecula has a hazardous vegetation (weed abatement) program in place to reduce wildfire risk and minimize potential harm to people and property.
Property owners are required to keep their properties free of hazardous vegetation throughout the year which keeps our community safe. Vegetation management is one of the most effective fire prevention measures. To help property owners keep up-to-date with the latest information, the City recently launched a comprehensive weed abatement webpage that includes frequently asked questions, a sign-up for email alerts, and information about the weed abatement process. You can check it out here: TemeculaCA.gov/weeds.