This document provides guidance on developing a standardized weed mapping program for the California Department of Food and Agriculture (CDFA). The goals are to increase the effectiveness of CDFA's statewide weed management program by implementing integrated weed mapping on local and state levels. The document covers various methods for data assembly and acquisition, including hand mapping, GPS mapping, computer mapping, and applications of geographic information systems (GIS) to analyze spatial distributions of weeds and compare infestations over historical time periods. Standardized mapping across agencies and personnel will help quantify weed management plans, identify problem areas, understand invasion processes, and allocate resources more effectively.