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Memo_CarbonSequestration_Feb2019Northampton Memo on Carbon Sequestration | Linnean Solutions 1 MEMORANDUM To: The City of Northampton From: Linnean Solutions Date: February 18, 2019 Re: Research and recommendations for approaches to enhance carbon sequestration Note: This memorandum is written to share the research behind the strategies developed for carbon sequestration. The content of this memorandum will be included in the Appendix of the Northampton Climate Resilience and Regeneration Plan. While beyond the scope of this project, there is a wealth of further publications and ongoing research that discuss the species, forest and agricultural management processes, chemical processes, and climatic variables that will play a role in impacting the carbon balance between soils and biomass and the atmosphere. We recommend further research—and potentially collaboration with researchers in the biogeochemistry field—for further refinement of strategies to maximize carbon sequestration and storage potential. Context: Building Soil Carbon Soils represent the largest reservoir of terrestrial carbon on the planet, storing more carbon than vegetation and the atmosphere combined (Lorenz & Lal, 2012). The potential for carbon sequestration in urban soils, in particular, has far been underplayed in the literature, yet urban areas retain significant percentages of soil cover that can positively contribute to regenerative land practices and climate change mitigation (Brown, Miltner, & Cogger, 2012; Renforth, Edmondson, Leake, Gaston, & Manning, 2011). Strategies for enhancing carbon sequestration and storage within biomass (i.e., trees and other vegetation) largely go hand-in-hand with efforts to increase the soil carbon pool. The health and carbon-carrying capacity of soil depends on a number of factors, including compaction, erosion, decomposition, plant productivity, and maintenance (Renforth et al., 2011). Data on these specific factors are therefore key to understanding which strategies will be most appropriate by location and soil condition, and evaluating the city’s soil cover and soil conditions is a useful starting point for understanding the potential for carbon sequestration through proactive urban soil management. A soil evaluation of this type can take a number of forms; the European Union’s Urban Soil Management Strategy program, for example, recommends the following steps for the practical implementation of urban soil management: 1. Data collection on soil quality, including contamination and land take; 2. Evaluation of soil quality, current land use, existing urban development concepts and plans; Northampton Memo on Carbon Sequestration | Linnean Solutions 2 3. Definition of goals for soil protection, including thresholds for acceptable land consumption and the resulting needs for soil management; 4. Selection and application of the most promising strategies and tools for urban soil management; 5. Monitoring of soil management implementation; 6. Evaluation of goals achievement. A soil management strategy lays the groundwork for tracking changes in soil health, and a deliberate process for enhancing carbon sequestration and storage, biological activity, and water infiltration. It also further justifies conscious and proactive policies for conserving the city’s healthy soils. The subsequent sections of this memorandum review a range of strategies currently being employed or actively studied as techniques for increasing soil carbon sequestration and regeneration along three core opportunity areas: forests, parklands, and agricultural land. Carbon Sequestration Strategies 1. Forests Forests (including both their soils and biomass) represent significant resources for climate mitigation and are the largest contributors to carbon sinks in the United States (Chitkara & McGlynn, 2018). Despite the majority of Massachusetts forests being relatively young, recent studies estimate that forestland in Massachusetts sequesters roughly 13 percent of the annual energy sector emissions in the state (De la Cretaz, Fletcher, Gregory, VanDoren, & Barten, 2010; Orians & Berbeco, n.d.). Regenerative forest management techniques can help increase forest carbon sequestration rates and enhance carbon storage, both in soils and biomass. These include: a. Avoided conversion (protection): Managing urban and agricultural development to protect forestland from conversion or disturbance, often coupled with protections like conservation easements. Maintenance and acquisition of conserved forestlands will be a key tool for ensuring that the city maintains its current capacity for sequestering carbon. Mature forests offer enormous ecological benefits far beyond those of young or regenerating forests (Chazdon, 2008; Nowak & Crane, 2002), including greater carbon storage, biodiversity, water infiltration, and soil health, which makes conservation of mature forests a top priority. Healthy trees over 77cm in diameter have shown to sequester 90 times more carbon, and store approximately 1,000 times more carbon, than healthy trees under 8cm in diameter (Nowak & Crane, 2002). Northampton Memo on Carbon Sequestration | Linnean Solutions 3 Over the past two decades, Northampton has worked to acquire and conserve prime forestland (as well as other highly valuable natural areas). Today, over 20% of the city’s land area is permanently protected open space, including 1,241 acres (502 hectares) of Chapter 61 forestland as of 2010 (City of Northampton, 2010). While Chapter 61 parcels are considered only “temporarily protected,” the City is entitled to the right of first refusal to purchase a parcel should the property be proposed for conversion to a program-ineligible use. Likewise, the City’s 2010-2018 Open Space, Recreation, and Multi-Use Trail Plan (Open Space Plan) delineates further action the City intends to take to acquire and preserve intact ecological areas, eventually aiming to reach 25% of the city’s land area. Carbon sequestration rates associated with existing forests vary greatly depending on forests’ rates of growth, species composition, soil carbon saturation, and size, in addition to factors such as climate. Project Drawdown estimates carbon sequestration rates for temperate forests at 3.0 metric tons of carbon per hectare per year based on 18 data points from eight sources; Nowak & Crane (2002) estimate an average urban forest carbon sequestration rate of 0.8 metric tons of carbon per hectare per year in urban areas of Massachusetts. Forest carbon assessments have furthermore shown that an acre of forest in Massachusetts contains roughly 85 tons of carbon, stored across the root systems, bark, foliage, dead wood, understory vegetation, forest floor (litter), and soil. According to the City’s Open Space Plan, Northampton has 11,607 acres (4,697 hectares) of non-protected forestland. For schematic purposes based on the sequestration rates above, losing these acres of forests to development would mean that the city would lose the capacity to sequester 3,758 – 14,091 metric tons of carbon per year, in addition to the impact from releasing the stored carbon from the land conversion. b. Forest restoration and regeneration (expansion): Identifying and capitalizing on opportunities for reforestation and afforestation, especially on already degraded soils where forest ecosystems can have the greatest regenerative benefit. In addition to maintaining existing forests, expanding the city’s forestland through forest restoration and regeneration will enhance the city’s capacity for further carbon storage and sequestration. The City’s Open Space Plan notes the explicit goal of replanting cleared areas with native species for several of the City’s existing conservation areas, such as Fitzgerald Lake Conservation Area. For private property, landowners of Chapter 61 forests are required to submit a forest management plan outlining property resources and long-term management objectives, making a commitment to improving the quality and quantity of timber on their land. Chapter 61 forest management plans include details of the protected land such as the presence of abandoned fields, which may then become highlighted as opportunities for afforestation. Working with this kind of data and with individual landowners, the City can advocate for afforestation where the greatest potential in terms of land area and landowner willingness exists. The City may find additional opportunities for afforestation by examining other types of degraded lands, such as brownfields, abandoned farmland, and other underutilized open spaces. Northampton Memo on Carbon Sequestration | Linnean Solutions 4 Project Drawdown estimates the carbon sequestration potential of temperate forest restoration (i.e., healthy forest replacing degraded forest) at 3.0 metric tons of carbon per hectare per year and the carbon sequestration potential for afforestation (i.e., planting forest where there was none before) at 4.7 metric tons of carbon per hectare per year. (For any timber that is being harvested, this carbon release would need to be factored into any carbon balances.) These estimates are drawn and averaged from a number of studies globally, and thus rates for local forests would vary. Nevertheless, it offers a baseline for understanding the potential for increasing carbon sequestration through forest expansion. c. Enhanced forest management (increased health and productivity): Promoting growth in existing forests using sustainable forestry practices as well as techniques to maximize forest biomass and promote forest soil health. Increasing forest productivity increases carbon input into the soil, thereby enhancing the carbon storage capacity of the “stable pool”—that is, storage in the mineral soil that is not released through the decomposition of organic matter (Jandl et al., 2007). Minimizing disturbance in the forest structure and soils reduces carbon loss. Techniques that have been shown to help maximize forest biomass, build forest soil health, and prevent erosion include the application of organic matter or biosolids (i.e., sludge and compost) or wood chip mulches on the forest floor (Beesley, 2012; Lal, 2005; Scharenbroch & Watson, 2014), and strategic placement of organic matter berms on watershed embankments (Tyler, 2001). These strategies constitute a form of enhanced forest management and can be used in all of the above scenarios (reforestation, afforestation, and existing forest protection). The rate and magnitude of carbon sequestration and storage (in both biomass and soil) varies by species, and so these processes can theoretically be amplified through selective planting of specific native species, with the understanding that climate and soil conditions will alter these parameters (Jandl et al., 2007; Scharenbroch, 2012). Generally speaking, for a given biomass trees with high wood densities accumulate more carbon than those with low densities (e.g., many deciduous species versus many coniferous tree species, respectively). Species with greater root depths have also shown a higher capacity to increase the pool of stabilized carbon in mineral soil (Jandl et al., 2007). In all cases, planting diverse native tree crops plays a key role in increasing soil sequestration over the long-term as stands of mixed species that occupy complementary ecological niches can reach higher levels of biomass production than pure stands; increase forest stability in a changing environment; and increase resilience to pests and disease (Chazdon, 2008; Jandl et al., 2007). There is an opportunity for the City to explicitly integrate long-term planning for increased carbon sequestration and storage through forest restoration and regeneration and enhanced forest management practices within forest stewardship plans for conservation land. Taking into account the experimental findings summarized above, we recommend the following strategies for continuing current efforts and adopting new practices that will help support carbon sequestration and storage goals. Northampton Memo on Carbon Sequestration | Linnean Solutions 5 Strategy Recommendation 1.1: Continue to protect, grow, and enhance the city's forestland and its capacity to store carbon. Continue the City's ongoing efforts to conserve prime forestland, particularly large blocks of mature and contiguous forestland, which support water infiltration, help conserve water supplies, keep the city's air cleaner and cooler with higher temperatures, as well as play a significant role in carbon sequestration. Continue to seek opportunities for open space acquisition in accordance with the City’s Open Space, Recreation, and Multi-Use Trail Plan, and maintain policies such as the City's right of first refusal to purchase a parcel of Chapter 61 forestland should the property be proposed for conversion to a program-ineligible use. In addition to conservation, continue identifying opportunities to replant cleared areas with diverse native species in the City’s existing conservation areas, as well as any brownfields, abandoned farmland, or other underutilized open spaces. The capacity of the city's forestland to sequester carbon can be further increased through enhanced forest management. Consider adopting practices for management of public lands that prioritize carbon sequestration and storage such as the inclusion of long-term carbon sequestration and storage planning in forest stewardship plans, and education programs for the adoption of similar practices on private land. Strategies such as the application of organic matter or biosolids (i.e., sludge and compost) or wood chip mulches on the forest floor, and strategic placement of organic matter berms on watershed embankments can help build soil organic matter, maximize forest biomass, and prevent erosion—all of which will play a role in increasing carbon sequestration and storage capacity. Further protecting and enhancing the diversity of tree species within the city’s forests, will also increase forest stability, resilience, and long-term benefits for carbon storage. Strategy Recommendation 1.2: Conduct a tree and forest ecosystems vulnerability and resilience assessment. Note: This strategy focuses on building the resilience of Northampton’s forests, which ultimately goes hand-in-hand with protecting forestland and its capacity for sequestering carbon. Conduct a citywide inventory of tree populations and forest ecosystems, identifying locations of large stands of tree species that are vulnerable to invasive species, pests, and local climate changes. Since ecosystems do not follow property boundaries, the assessment will be most effective if trees, stands, and forests are assessed across both public and private property, and if the City works with partners such as property owners, farmers, and local ecologists in conducting the assessment. Develop City strategies such as ongoing monitoring protocols, selective harvesting, adaptive species planting, invasive species removal, and improvements to soil health, among others in tandem with a public campaign to help raise awareness around addressing vulnerabilities in tree stocks and ecosystems. Emphasize strategies that will simultaneously support carbon accumulation in forest biomass and soils, such as organic amendments and enhancing species diversity in tree stands. Northampton Memo on Carbon Sequestration | Linnean Solutions 6 2. Municipal Parkland Opportunities exist for Northampton to capitalize on its parks and landscape plantings in service of carbon sequestration and soil regeneration. Continuing to pursue the goal to “reclaim pavement for parks,” as laid out in the City’s Open Space Plan, presents one avenue for making more land available for carbon sequestration in plants and soils. Adopting or enhancing landscape management practices with a focus on carbon sequestration and storage, such as through the application of soil amendments, will be another way to enhance the potential of public parkland. The soil cover types associated with parklands are particularly well-suited to amendment application because they are “no-till” environments, minimizing the counterproductive effects of soil disturbance (Brown et al., 2012). A 2012 study from Tacoma, WA of the sequestration potential of turfgrass and landscape planting demonstrated significant gains in carbon storage over a middle-term (5-15 year) period through use of organic soil amendments (Brown et al., 2012). Although organic amendments such as composted biosolids, food waste, and yard waste are traditionally added to soils for the purposes of improving plant growth and reducing runoff, Brown and colleagues demonstrated the additional benefits of carbon sequestration at rates similar to those of no-till agriculture. Their results are summarized as the following: Soil cover type Development type Amendments C sequestration potential (5-15 year) (metric tons / hectare) Turfgrass New 4cm compost 2-20 Turfgrass Existing 4cm compost 12-13* Landscape plantings New 8cm compost 4-5 Landscape plantings Existing 8cm compost 13 Vacant land Restoration 8cm compost 2-2.5 * Rate reflects sequestration after subtracting mower emissions associated with turfgrass management. Drawn from this research, best management practices for post-development soil amendments mandate the application of 7.5cm of compost for landscape beds, and 4.5cm for turfgrass, with compost containing approximately 22% carbon and 2% nitrogen. These one-time applications have shown to increase average carbon sequestration by 0.22 metric tons per hectare per year over a 15-year time-frame (Brown et al., 2012). The Northeast Organic Farming Association (NOFA) provides additional recommendations for landscape management practices to increase soil carbon storage: • Emphasize perennials in plantings (particularly native plants) and use annuals to fill gaps (reduces soil disturbance and promotes soil aeration and infiltration). • Minimize the use of pavement and unproductive mulch. • Use biological controls instead of fungicides and pesticides. Northampton Memo on Carbon Sequestration | Linnean Solutions 7 • Rule out synthetic nitrogen fertilizers on athletic fields, institutional campuses, and public park lands. • Incorporate nitrogen-fixing trees and perennials into the landscape. • Mow, cut back, and/or heavily mulch over weeds instead of pulling. • Establish a composting area for your municipality—or deliver to a commercial composting company. While establishing a municipal composting program is not a feasible priority for Northampton in the short-term, the City may want to consider the opportunity to take advantage of compost collection in its long-term planning. The City of Tacoma, WA, in association with the research mentioned above, has capitalized on synergies between carbon sequestration, carbon mitigation, and waste diversion. A large proportion of the organic amendments applied in the city are produced from locally collected food waste, yard waste, and biosolids, and then re-sold to homeowners and developers for compliance with local stormwater management ordinances that require amendment application post-development, or other purposes such as public park landscaping, urban agriculture, commercial and roadside landscaping, and home garden fertilization (Brown et al., 2012). This circular model helps the City to reduce its emissions associated with landfilled organic materials and provides a revenue stream that offsets the cost of the composting program. The combined stormwater policy and municipal composting program has created wider use of organic soil amendments; researchers estimate the total potential carbon sequestration from the application of locally-produced organic amendments at 1,500 metric tons of carbon per year. Worth noting, these practices have also shown to improve soil infiltration rates, and thus concurrently have the potential to improve local water quality and stormwater management (Brown et al., 2012). Taking into account the experimental findings summarized above, we recommend the following strategy for supporting carbon sequestration and storage goals in municipal parkland. Strategy Recommendation 2.1: Adopt landscape and parkland management practices that amplify soil carbon storage. Adjust or adopt new municipal landscaping and parkland management practices to enhance the city's soil carbon storage. Organic amendments, in particular, can amplify the carbon storage capacity of soils. Best management practices for post-development soil amendments recommend the application of 7.5cm of compost for landscape beds, and 4.5cm for turfgrass, with compost containing 22% carbon and 2% nitrogen. One-time applications of such amendments have shown to increase average carbon sequestration by 0.22 metric tons per hectare per year over a fifteen-year timeframe. Additional landscaping and parkland management strategies to enhance soil carbon storage could include: emphasizing native perennials in plantings and using annuals to fill gaps; minimizing the use of pavement and unproductive mulch; using biological controls instead of fungicides and pesticides; eliminating synthetic nitrogen fertilizers on athletic fields, institutional campuses, and public park lands; incorporating nitrogen-fixing trees and perennials into the landscape; and mowing, cutting back, and/or heavily mulching over weeds instead of pulling. These strategies for enhancing soil health also support stormwater infiltration. Northampton Memo on Carbon Sequestration | Linnean Solutions 8 3. Agricultural Land Soil cultivation through plowing or other tillage methods releases carbon dioxide into the atmosphere through the mineralization of soil organic carbon. Consequently, studies that focus on mechanisms for improving soil health and maintaining or enhancing carbon capture capacity point to practices that minimize soil disturbance and encourage the proliferation of healthy microbial communities. These approaches include regenerative agriculture practices, as well as specifically agroforestry and silvopasture (Toensmeier, 2016). The City’s Open Space Plan mentions the City’s and residents’ interests in encouraging regenerative agriculture, and highlights all three approaches—regenerative agriculture, agroforestry, and silvopasture—as potential recommended uses, specifically for the Bleiman Parcel in the Meadows. These three practices and their carbon sequestration potential are further explored below. a. Regenerative Agriculture: Enhancing and sustaining the health of the soil through agricultural practices that restore its carbon content, which in turn improves productivity. The principles of regenerative agriculture support the explicit goals of minimizing soil disturbance, enhancing site biodiversity, and maintaining microbial communities to support soil health, and specifically maintain soil organic carbon. Core approaches of regenerative agriculture include: • Minimum soil disturbance – adoption of no-till or low-till approaches to prevent soil carbon emissions and microbial community disruption; • Adequate surface cover – use of mulch or cover crops to protect soils from oxidation, compaction, and erosion, and to enhance carbon sequestration; • Crop diversity and rotation – use of diverse crops and rotations to enhance crop resilience against pests and promote soil and site biodiversity, further improving soil quality and productivity; • No chemical use – promotion of the use of organic amendments, such as biochar, manure and compost, with the understanding that synthetic fertilizers and pesticides are known to damage soil microbial communities and degrade soils over time. While the scale or extent to which no-till or low-till approaches increase carbon capture has recently come into question (Luo, Wang, & Sun, 2010; Powlson et al., 2014), research consistently shows positive effects of the collective application of conservation or regenerative agriculture approaches (i.e., reduced tillage, use of cover crops, organic amendments, etc.) on increasing soil carbon (Poeplau & Don, 2015; Syswerda, Corbin, Mokma, Kravchenko, & Robertson, 2011). As a whole, Project Drawdown estimates the carbon sequestration potential of adopting regenerative agriculture practices at 0.6 MTCO2e per hectare per year. As a schematic exercise, the City’s roughly 5,000 hectares of protected agricultural land (including Chapter 61A and Agricultural Preservation Restriction lands) have the potential to sequester approximately 3,000 MTCO2e per year if regenerative agriculture practices are maximally adopted. (This exercise omits the fact that regenerative agriculture practices are already being Northampton Memo on Carbon Sequestration | Linnean Solutions 9 practiced in some cases.) Regenerative agriculture would include the further benefits of increasing water holding capacity, reducing erosion, and maintaining soil structure and organic content. b. Agroforestry: Integrating trees (or other woody crops) into traditional cropland. Also known as “tree intercropping,” agroforestry refers to the integration of trees into traditional cropland, along field borders and stream banks (riparian buffers), as strategic windbreaks, in less productive areas of fields, and between rows of crops. The practice has long been touted for enhancing and maintaining long-term soil productivity, ecosystem functional and structural diversity, as well as carbon sequestration and storage potential—both in the tree biomass as well as soil carbon stocks (Jose, 2009). According to estimates by Project Drawdown, introducing agroforestry can increase carbon sequestration on agricultural lands by 1.3 MTCO2e per hectare per year, assuming no other changes to conventional practices are made (i.e., conventional tillage and annual crops are maintained). As a similar schematic exercise as used for regenerative agriculture, introducing agroforestry to Northampton’s roughly 5,000 hectares of protected agricultural land (including Chapter 61A and Agricultural Preservation Restriction lands), could result in carbon sequestration enhancements on the order of 6,500 MTCO2e per year if maximally adopted. Riparian buffers and windbreaks are highlighted as particularly beneficial practices for soil health (Kittredge, 2015). Riparian buffers stabilize soils along waterways, preventing erosion, and improving water quality in the process; windbreaks likewise prevent gusts or storms from displacing soil, and help to keep soil carbon in the ground. When the incorporated trees are also yield-bearing (e.g., fruit, nuts, mushrooms), farmers may benefit from crop diversification and be better insulated from risk. Additional benefits can include increased drought resilience of the landscape, leading to improved climate resilience over time. c. Silvopasture: Integrating trees (or other woody crops) into pastures for livestock grazing. As a form of agroforestry, silvopasture involves the addition of trees into a traditional pasture landscape as an alternative to conventional livestock grazing. It offers the same benefits previously mentioned in agroforestry, including enhancing soil health, reducing erosion, increasing drought resilience, and diversifying crops to insulate farmers from risk, along with reduced climate stress on livestock. Furthermore, the presence of livestock has shown to increase fertility of forest ecosystems and enhance carbon storage substantially: based on estimates from Project Drawdown, the sequestration rate for silvopasture reaches 4.8 MTCO2e per hectare per year. The presence of trees and livestock concurrently contribute to the high sequestration rates: silvopasture landscapes have shown to sequester five to ten times as much carbon as the same landscape without trees. Northampton Memo on Carbon Sequestration | Linnean Solutions 10 Although animal grazing is not a significant land use in Northampton, the notable carbon sequestration benefits of such a model are worth considering. The City’s Open Space Plan again suggests that regenerative agriculture approaches such as silvopasture may be an appropriate recommended use for sites such as the Bleimen parcel. More generally, silvopasture highlights the opportunity for closed-loop, self-sustaining models for replenishing water and nutrients, including soil carbon. Farmer outreach and peer-to-peer education have shown to be successful avenues for spreading adoption of silvopasture and other agroforestry systems. As such, the City may consider a partnership with local and regional farming initiatives and organizations (e.g., Smith Vocational and Agricultural High School, Keep Farming Northampton, the Northeast Organic Farming Association, etc.) to develop and promote a peer education program. Accordingly, we recommend the following strategies for supporting carbon sequestration and storage goals in the City’s agricultural land. Strategy Recommendation 3.1: Support education and training in regenerative agriculture systems, including agroforestry and silvopasture. Identify opportunities to support education and training in regenerative agriculture, agroforestry, and silvopasture systems for farmers interested in working with those methods. Regenerative agriculture approaches aim to minimize soil disturbance, enhance site biodiversity, and maintain microbial communities to support soil health. Agroforestry (the integration of trees in agricultural land) and silvopasture (the integration of trees and livestock grazing) are forms of regenerative agriculture that bring additional ecological and economic benefits such as crop diversification. Trees planted along riverbanks (riparian buffers) and as windbreaks stabilize soils, prevent erosion (thereby improving water quality), and retain carbon in the ground. All three practices— regenerative agriculture, agroforestry, and silvopasture—have shown to increase carbon sequestration potential of agricultural lands by 0.6 MTCO2e, 1.3 MTCO2e, and 4.8 MTCO2e per hectare per year, respectively. Additional benefits can include increased drought resilience of the landscape, leading to improved climate resilience over time. Consider peer-to-peer learning models through collaboration with local and regional farming initiatives with the explicit goal of developing contextually-specific practices for enhancing carbon sequestration and storage. Use such collaborations as a platform for identifying adjustments to municipal policies or systems, such as aligning lease lengths with harvest rotations for longer-term perennial plantings, that can further facilitate adoption of regenerative agriculture practices. Strategy Recommendation 3.2: Serve as a pilot community for the Massachusetts Healthy Soils Action Plan. Serve as a pilot community for the Massachusetts Healthy Soils Action Plan. The Massachusetts Executive Office of Energy and Environmental Affairs is contracting the development of a Healthy Soils Action Plan for the Commonwealth over the course of 2019- 2020, which will become a blueprint for improving farming, forestry and lawn care practices to reduce erosion, improve production, increase carbon sequestration and storage, and better withstand intensive weather events and droughts. The project involves collaboration with a Working Group to develop the action plan, as well as listening sessions with representatives Northampton Memo on Carbon Sequestration | Linnean Solutions 11 from farming, forestry, municipal, urban/suburban residents, and institutional and business land owners across the state. Northampton City staff, residents, institutions, and agricultural sector can engage by both contributing to the plan's development (as part of the Working Group or by attending the listening sessions) as well as becoming early adopters of the plan's strategies. 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