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Cover cropping has been proposed as an important component of integrated weed management strategies due to its potential effects on multiple demographic processes, including weed seedling emergence from soil, plant survival, seed production, and seed predation. In this article, we report the results of modelling analyses that investigated how a cover crop could affect the population dynamics of Amaranthus tuberculatus (Moq.) J.D. Sauer (waterhemp), an annual dicotyledonous species that is a major problem in maize and soyabean fields in the central USA. We constructed difference equation models for maize–soyabean rotations with and without a rye cover crop and parameterised the models with values drawn from published scientific literature. Results of the analyses indicate that the use of a winter cover crop would have minimal effects on the level of herbicide efficacy required to prevent increases in A. tuberculatus population density in maize and soyabean. However, if a high level of herbicide efficacy was imposed, cover crop‐derived reductions in A. tuberculatus seedling population density, delays in seedling emergence, and increases in seed predation would diminish A. tuberculatus seed population density in soil up to 96% over a 10‐year period. Thus, while cover crops did not replace the need for other control strategies for A. tuberculatus, they could complement them. Relative to cover crops, greater benefits for A. tuberculatus management might be gained using diverse sequences of cash crops. Possible synergies between cover crops and diversified crop rotations should be explored in both field experiments and modelling analyses. [ABSTRACT FROM AUTHOR]

A growing body of research suggests that although sustainable agriculture, particularly agroecology, can address challenges such as those related to climate change, ecosystem services, food insecurity, and farmer livelihoods, the transition to such systems remains limited. To gain insight into the state of U.S. sustainable agriculture and agroecology, we developed a 28-question mixed-method survey that was administered to scientists in these fields. Respondents (N=168) represented diverse locations, institutions, and career stages. They offered varied definitions of sustainable agriculture, with 40% considering economic and social well-being to be core components. Respondents identified the amount and duration of public research funding as important obstacles to conducting research on sustainable agriculture (85% and 61%, respectively). Further, most expressed challenges in communicating findings beyond academia, including to the media and policymakers, potentially limiting the impacts of such research. However, respondents expressed satisfaction in several areas, including relationships with community members (81%) and local producers (81%), and interest from students (80%) and research communities (73%), suggesting positive momentum in this field. Earlier versus later career scientists rated research on “human dimensions” as more important, expressed greater concerns over career stability, and were less satisfied with opportunities for policy engagement. Results imply that greater public investments, particularly fostering human dimensions, could support a transition to agroecology and its associated benefits. [ABSTRACT FROM AUTHOR]

The article addresses the experience of graduate students working in a unique and transformative transdisciplinary environment with the goal of offering examples of successful collaboration, challenges met and opportunities for continued success to future practitioners of team science that addresses complex social and ecological challenges. It cites the Climate and Corn-based Cropping Systems Coordinated Agricultural Project as a collaboration of 11 midwestern institutions that span 9 states.