Large scale management of weed populations is vital to decreasing propagule pressure and reducing weed seedbanks, two of the principle process targets in integrated weed management strategies.Unfortunately, demands for improved management techniques will escalate in many areas as herbicide resistance (HR) expands. One strategy–cooperative weed management areas (CWMAs)–have been a fixture in western rangeland systems, and are increasingly being adopted to manage invasive plant populations in the eastern U.S. CWMAs are defined loosely as coalitions of neighboring landowners, natural resource agencies, and conservation organizations that pool and distribute public and private resources to optimize regional weed control. As plant dispersal is not restricted by land ownership boundaries, and both the direct and indirect movement of weed seeds is facilitated by the agricultural infrastructure, whether through contaminated feeds or manure, use of non-certified seed, or weed seeds carried on farm equipment transported or used across broad areas, a more regional or landscape approach to weed management may be an important innovation in traditional Midwestern row cropping environments.
Why Public Lands Have Adopted CWMAs?
CWMAs have been effective across the West in managing infestations that cross boundary lines or require expensive or intensive treatments. For instance, Montana and Nevadahave ongoing and active programs to develop and coordinate Cooperative Weed Management efforts. In cropping systems, successful regional cooperative efforts have been implemented to reduce the prevalence of cotton boll weevil and stem the spread of citrus diseases. However, these types of cooperative arrangements have been rare in cropping systems, particularly in the eastern U.S., and have been primarily system or problem specific.
Why Private Landowners Will Benefit from Working Cooperatively?
A problem such as weed herbicide resistance gives rise to a situation in which individual, on-farm, practices affect common pool resources (i.e., resistance susceptibility), resulting in a tradeoff between the immediate benefits of highly effective weed control through herbicide application coupled with HR crops, and the long term efficacy of these management tools (i.e., herbicides and HR crops), and system productivity (quality of ecosystem services). Long term investments in sustainable practices can improve system health and management efficacy over time, but experience has shown that the net benefit of these investments cannot be optimized piecemeal, with no coordination at the landscape-scale of weed populations and control of post-harvest transport.
In rangeland systems and other invasive plant management efforts, control strategies and knowledge dissemination has benefited from cooperative networks of landowners, managers, and researchers involved in the development and implementation of pest control technology. Multiple studies have suggested coordinated management above the farm-scale is necessary to reduce regional weed populations, and increase the sustainability of weed control options; however, this represents just as much of a social dilemma as ecological one. Practices that are optimal at the farm-scale do not necessarily result in landscape-scale benefits, and implementation of alternative management strategies necessitates both agronomic and cultural changes.
What Are Legal Tools for Encouraging and Facilitating Private Cooperative Weed Management Areas?
As mentioned in the previous section, a coordinated management scheme is needed for successful invasive management as a tool for farmers to fight herbicide resistance. While the science is clear, the social dilemma of how to facilitate cooperative work between neighboring farmers over a certain geographic boundary is a hurdle to CWMA formation and long-term success. Existing state-level laws that attempt to solve the issue generally fail to regulate invasive plants. These weak rules cover, on average, only 20% of the species considered invasive by scientific authorities. When regulatory systems fail to cover disputed topics, it falls upon individual farmers and landowners to develop alternative strategies. There are several possible solutions with varying governmental involvement to promote the use of private CWMAs; including private action, state regulation, or a hybrid model of public-private engagement whereby the state creates supporting structures for private CWMAs. All options require individuals to contract with each other to ensure long term success and establish roles and responsibilities of the members.
Private action requires private individuals and business to contract with each other to reach a desired outcome. Much like the CWMAs for public lands, a private CWMA should contain clauses that clearly define the purpose of the agreement, specify the boundaries of the CWMA and adapt the rules to local conditions, specify who the members are, decide how accountability and monitoring of progress will work, impose sanctions for violations of the agreement, contain conflict resolution mechanisms, and detail the governance structure. Future work by the authors will develop model private agreements for the establishment of voluntary CWMAs.
In addition to private contracts, policymakers may find that state regulations would help increase the likelihood and willingness of farmers to adopt CWMAs. Model statues can clarify the terms of each clause discussed in the section above, while giving more teeth to the legitimacy of the CWMA through state endorsement of incentives and enforcement clauses. Another regulatory option is to craft statutes that govern the formation, governance and conflict resolution of a farmer’s association that would resemble the already existing framework of homeowner’s associations.
There is no clear answer as to which option–private action, state regulation or a hybrid model–is the most effective for encouraging the adoption of private CWMAs. However, the current uncoordinated practices by landowners and farmers demonstrate a need for a more nuanced and comprehensive framework to promote establishment of CWMAs in order to better manage invasive species and slow the rate of herbicide resistance.
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 Lauren D. Quinn et al, Navigating the "Noxious" and "Invasive" Regulatory Landscape: Suggestions for Improved Regulation, 63 BioScience 124 (2013).
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