About

Donors and investors need guidance on which organizations to support. This guide provides the public with information about what is known about the characteristics, practices, and transparency of organizations, in order to identify organizations with exceptional standards in key areas of practice and incentivize collective improvements across the field so that the substantial enthusiasm and funding for reforestation results in the best outcomes for the biodiversity, climate, and people of this planet.

We reviewed the practices of reforestation organizations based on a combination of a survey completed by many organizations and web-based information when organizations did not complete our survey. Specifically, our study focuses on “intermediary” organizations, which we broadly define as groups involved in the tree growing movement that lead programs and large-scale initiatives aimed at supporting networks of smaller local implementing groups across broad geographic areas; some also implement their own local projects. Our emphasis on intermediary organizations seeks to address the leaders in the field whose various administrative and implementing practices are likely to be adopted by many local organizations, both those existing and yet to be established. Moreover, it would be impossible to evaluate the thousands of local organizations and agencies engaged in tree growing across the globe,

In a precursor study, using only web-based information (Schubert et al. 2024), we found that tree growing intermediary organizations broadly recognize the importance of many best practices, such as clear goals, local community involvement, and monitoring, yet many key details were not readily available. Given that organizations do not necessarily share all this information on their websites, we designed a survey to elucidate greater detail on key questions about organizational practices and policies.

In collaboration with Mongabay and with funding from the Center for Coastal Climate Resilience and the MacArthur Foundation Endowed Chair at the University of California, Santa Cruz, we sent surveys to 125 intermediary organizations about how they follow best practices for tree growing recommended by numerous experts in the field. We divide these into four categories:

• Permanence - Although many projects focus on the number of trees planted, for projects to achieve the desired ecological, social, and carbon sequestration goals it is essential that trees are maintained over time. Hence best practices for ensuring project longevity are key to successful outcomes, regardless of specific project objectives. We have more criteria in this category and consider it the most important and generalizable in evaluating organizations.

• Ecological - Enhancing biodiversity and ecosystem services (e.g. water quality, flood control) is a stated goal of many tree growing projects. All projects at minimum should aim to have no net negative effects on these factors.

• Social - Many projects aim to enhance human livelihoods and equity, and community engagement is key to the success of nearly all projects except some on remote public lands or large private landholdings. At minimum projects should not displace landholders without offering alternative income or unintentionally exacerbate social conflict.

• Financial - It is important for funders to know how their money is being spent and for organizations to ensure that funding covers the cost not only of implementation but also maintaining projects over the longer time period required to reach most reforestation goals.

Public transparency of information is important for funders, policymakers and others to be able to verify outcomes of tree growing projects and is integrated across the four categories.

Survey Methodology

We designed a survey of 29 questions intended to provide details about organizational policy and practice across four categories: permanence, ecological, social, and financial (Survey Template). Questions included a mix of closed- and open-ended questions and organizations could elaborate on most closed-ended questions if desired. We sent the survey as a Google doc so that multiple organizational representatives could contribute to the survey if desired. Informal feedback from survey respondents indicated that the survey took 0.5-3 hours to fill out depending on the survey respondents’ referential knowledge of reforestation programs, and the need to consult documents or gather responses from other organization staff. We encouraged survey respondents to share and reference sections of report or protocol documents relating to the survey prompts, where the information was already well developed, instead of writing out lengthy responses. Our team reviewed those documents and incorporated the information into our evaluation system.

Beginning October 2024, we contacted organizations to request direct participation in the survey. We used organization websites to locate official contact information. We addressed our communications directly to email addresses of organizational leaders or scientific staff whenever available, and secondarily used “info@” addresses, web forms, when only these were available. We systematically contacted each organization by first sending an invitation and two reminder messages via email. If we received no response to our messages, we followed up by calling listed telephone numbers. We explained, at multiple phases of our communication with organizations, that a summary of data from the survey would be shared publicly through a list of organizational reforestation practices we were developing with Mongabay. If we received a reply from an organization, we shared our survey and asked that it be completed by people within the organization with appropriate program knowledge. Primary contact people and survey contributors included senior executives, forestry specialists, and program officers.

We offered each participating organization a 3-week provisional deadline to complete the survey and extended that up to two months if requested. We sent at least two standard reminder messages and also encouraged communication with our team to answer questions when participants were uncertain how to interpret certain questions. Our survey period formally closed 30 June 2025.

For all organizations that either did not respond to our survey invitation or declined to complete the survey, we performed systematic reviews of organization’s websites and publicly available reports to seek answers to our survey questions between January and June 2025. Each review involved multiple screenings by at least two trained project members, plus final proofing by SCS. We navigated to all website pages and reports to collect information on tree growing operations and standards. Cumulative review times ranged 80-200 min per organization, depending on the extent of information available.

Additionally, we collected information on any standard or certification labels that organizations referenced. We reviewed these standards, independently from organizations, to assess the extent to which their compliance measures addressed the questions on our survey. These standards were then used to infer practices and populate relevant sections of the data if the topic was not otherwise addressed explicitly by organization policy descriptions. Furthermore, if the standard’s compliance was at a higher level than the information provided by the organization’s survey or website, we upgraded the response. If multiple standards were listed as varying from program to program, the lowest-level commitment among these was chosen as the baseline standard.

References

• Brancalion, P. H. S., & Holl, K. D.(2020). Guidance for successful tree planting initiatives. Journal of Applied Ecology, 57, 2349–2361.


• Di Sacco, A. et al. (2021). Ten golden rules for reforestation to optimize carbon sequestration, biodiversity recovery and livelihood benefits. Global Change Biology, 27,1328–1348.


• Elias, M. et al. (2022). Ten people-centered rules for socially sustainable ecosystem restoration. Restoration Ecology, 30,e13574.


• Fleischman, F., et al. (2020). Pitfalls of tree planting show why we need people-centered natural climate solutions. Bioscience, 70, 947–950.


• Holl, K. D., & Brancalion, P. H. S. (2022). Which of the plethora of tree-growing projects to support? One Earth, 5,452–455.


• International Tropical Timber Organization (ITTO). (2020). Guidelines for forest landscape restoration in the tropics. ITTO Policy Development Series No. 24.


• Löfqvist, S. et al. (2022). How social considerations improve the equity and effectiveness of ecosystem restoration. Bioscience, 73, 134–148.


• Schubert, S. C. & Holl, K. D. et al. (2024). Advances and shortfalls in applying best practices to global tree-growing efforts. Conservation Letters, 17:e13002.


• Sousa-Silva, R. et al. (2023). Keys to better planning and integrating urban tree planting initiatives. Landscape and Urban Planning, 231, 104649.