Ecological management of invasive weeds will require substantial increases in the application of ecological knowledge and its integration with other forms of knowledge. To enable these increases, we call for purposeful development of knowledge networks in which new knowledge about a complex situation is created by the interaction of different forms of knowledge. We believe that invasive-plant management must be based on a fine-tuning of managed ecosystems, in which operations (e.g., farm activities) are comprehensively adjusted to confront invasives with a wide array of control measures. Land managers must have the primary role in this tuning process because of their holistic knowledge of the ecosystems they manage. Additionally, such ecological management of invasives will require support from new or improved practices in many relevant sectors, e.g., involving extension workers, farm advisors, and researchers of many sorts. Knowledge networks facilitate the creation, application, and integration of knowledge that will be needed to support ecological invasive-plant management. Worldwide, knowledge networks are under very active development as promising solutions to ecological-management challenges. To develop, networks require proactive organization and facilitation. We have developed an experimental knowledge network to facilitate ecological management of field-crop weeds on the basis of collaborative learning groups that help farmers and other professionals develop necessary knowledge. These groups have been favorably evaluated by most participants, and this article describes the results of our project, including our insights into development of such networks.