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Almost 1 billion hectares of land have been pledged for restoration globally under the UN Decade on Ecosystem Restoration. Seed‐based restoration will be essential to achieve native revegetation targets in a timely and effective manner. However, problematic seed germination, seeding environments, and seed handling can limit our ability to use native seeds in revegetation. Seed enhancement technologies (SETs) are post‐harvest seed treatments, which may improve seed performance and handling, thereby optimizing seed‐use efficiency and success in restoration. We highlight SETs as a restoration tool accessible to anyone and which can also be used to deliver seed‐based restoration at scale. If SETs are to rise to the challenge of restoration targets in the coming decade, improving native seed supply, research efforts, knowledge and data sharing, and collaboration and funding will be essential. These actions are discussed within a roadmap for advancing SETs in the UN Decade on Ecosystem Restoration. [ABSTRACT FROM AUTHOR]

• Proper seed source selection is key for tropical forest restoration/reforestation. • Piecewise structural equation models assessed phenotypic effects on seedling quality. • Scarification, not tree phenotype, drives germination success in Coulteria platyloba. • Provenance, rather than tree phenotype, affects seedling quality in C. platyloba. • Both natural and managed populations should be used as seed sources for this species. A major obstacle faced by reforestation/restoration programs is an insufficient supply of high-quality seed. Seed collection is commonly based on opportunistic strategies that only consider availability and distance to seed sources, but not seed quality. Although for commercial timber species from temperate ecosystems the selection of individuals with above-average phenotypes often results in high-quality seeds and seedlings, the validity of this criterion has not been assessed in tropical dry forests (TDF). By using the abundant TDF tree Coulteria platyloba as study model and piecewise structural equation modelling (pSEM), we examined the associations between germination success and seedling growth, and various tree, fruit and seed characteristics, for seeds from two provenances (natural vs. managed populations), that were either scarified or not. Unexpectedly, phenotypic attributes of trees, fruits and seeds had no effect on germination success, as this response variable depended on scarification only. Also, fruit quality was unrelated to tree size, but it was related to provenance. According to pSEM, the best supported path resulting in high quality seedlings established a relationship between managed populations, high quality fruits and seedlings with better roots systems, but only for seeds that were scarified and did not germinate very rapidly. Overall, the assessed relationships were complex, weak, and sometimes difficult to interpret. Nonetheless, these results provide guidance to improve seed source selection efforts that consider operation costs of nurseries and the success of future plantations. In TDF, selecting trees with above-average phenotypes as seed sources does not necessarily favour the quality of seedlings used to restore degraded areas. In these ecosystems, we recommend a seed collection strategy that combines managed and natural populations as seed sources to maximize genetic variability in future plantations, while improving nursery operation efficacy. [ABSTRACT FROM AUTHOR]

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Seed is fundamental to broadscale plant restoration when the goal is to re-establish species and ecosystems. But climate change is expected to significantly influence plant reproduction, affecting seed availability and viability as well as planting opportunities. Meeting growing restoration targets within these constraints in new and unfamiliar climates will be challenging. Consequently, we need to develop a range of flexible strategies to ensure that sufficient volumes of viable seed are available to take advantage of planting opportunities under novel environmental scenarios. This requires coordinated leadership to align funding and planting timelines, using seed production areas to improve seed supply, building and maintaining infrastructure to stockpile seed, encouraging research to overcome storage and germination constraints, and developing and implementing new technologies in all of these areas. Increased tolerance to risk and failure will also be required as the application of current restoration practices may not be appropriate as the climate changes. [ABSTRACT FROM AUTHOR]

It has been almost 15 years since concerns about the limited capacity of remnant native vegetation to supply the volumes of seed required to meet increasing restoration demands were first raised. Since that time little progress has been made towards addressing this constraint with the ongoing decline of native vegetation communities, especially since 2000, further challenging seed supply. We provide examples of the size of this demand for seed, as well as major issues associated with seed sourcing. We also discuss how invoking the concept of market forces to drive seed supply and demand is inappropriate and highlight the need for an industry body to oversee seed collection and utilisation standards. We further propose key actions that are required to secure the seed supply chain within the next 20 years to meet existing and future restoration targets. We argue that concerted, coordinated action at Commonwealth, State and regional levels are required to underpin effective future restoration outcomes. [ABSTRACT FROM AUTHOR]

Restoring degraded land to combat environmental degradation requires the collection of vast quantities of germplasm (seed). Sourcing this material raises questions related to provenance selection, seed quality and harvest sustainability. Restoration guidelines strongly recommend using local sources to maximize local adaptation and prevent outbreeding depression, but in highly modified landscapes this restricts collection to small remnants where limited, poor quality seed is available, and where harvesting impacts may be high. We review three principles guiding the sourcing of restoration germplasm: (i) the appropriateness of using ‘local’ seed, (ii) sample sizes and population characteristics required to capture sufficient genetic diversity to establish self-sustaining populations and (iii) the impact of over-harvesting source populations. We review these topics by examining current collection guidelines and the evidence supporting these, then we consider if the guidelines can be improved and the consequences of not doing so. We find that the emphasis on local seed sourcing will, in many cases, lead to poor restoration outcomes, particularly at broad geographic scales. We suggest that seed sourcing should concentrate less on local collection and more on capturing high quality and genetically diverse seed to maximize the adaptive potential of restoration efforts to current and future environmental change. [ABSTRACT FROM AUTHOR]