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Societal Impact Statement Large quantities of diverse native seeds are required to scale up global restoration efforts. However, it remains unclear for many ecosystems how the diversity of available seed in commercial stocks reflects the composition of the ecosystems where vegetation is being remade. This study highlights existing shortfalls in the diversity of seed presently available for use in restoration and identifies gaps in the seed supply chain while providing a new method for optimising species selection given these constraints. This work underscores how improved collaboration between stakeholders is required to strengthen the seed supply chain and help remake functionally diverse vegetation. Summary Restoration using native seed is frequently implemented to restore degraded ecosystems. However, it remains unclear how constraints on the diversity of germplasm available for use in restoration may limit the recovery of both species and plant functional diversity. Using a dataset of seed availability for Australia's major vegetation types, we explore variation in the diversity and breadth of functional traits (leaf mass per area, seed mass, plant height) for species where seed is available on commercial markets relative to unavailable. Using these data, we simulate theoretical seed mixes derived from two species pools: (1) constrained by the current market of commercially available seed, and (2) assuming all native species can be planted; then we compare differences in functional diversity (dispersion) as an exercise to explore possible limitations within the current seed supply. Seed from only 12% of Australian plant species (2992 species) is presently available for immediate purchase. Seed was more frequently available for trees and shrubs than for understorey species. Available species were on average taller, with thicker, longer‐lived leaves than unavailable species. Overall, functional dispersion was lower for seed mixes generated using available seed compared with those drawn from all species. Solutions are required to address seed shortfalls so that plantings are not only species rich but also functionally diverse. We develop two options: (1) quantifying and addressing gaps in the seed supply chain that currently limit the capacity for practitioners to restore diverse vegetation; and (2) applying a trait‐informed species‐selection method to plantings that maximises functional diversity using available seed.

Abstract Large‐scale ecological restoration is a crucial tool for improving the quality and extent of habitat for wildlife. In Australia, 25,000 hectares of land is to be restored to support habitat connectivity for the Endangered koala (Phascolarctos cinereus). However, limited funding is a barrier to achieving restoration of this scale without the integration of new technologies and approaches. Seed enhancement technologies (SETs) are commonly used in agriculture to improve plant establishment and growth while reducing seed wastage; yet SETs are rarely used in restoration. Here, we tested the efficacy of SETs with five native tree species favored by koalas. Using a greenhouse trial, we measured emergence, time to emergence, growth rates, and survival up to 7 weeks post planting. At 33 weeks post‐planting, we measured total biomass, root: shoot ratios, and the specific root length. SETs resulted in comparable emergence and survival and promoted a longer time to emergence relative to bare seeds. Importantly, seedlings grown from SETs yielded higher average growth rates (0.3 mm/week higher), total biomass (5.93 mg higher) and root: shoot ratios (0.258 higher) relative to seedlings grown without SETs. These findings underscore the applicability of SETs to native species to support large‐scale koala habitat restoration by increasing the growth rate and size of seedlings at the early life stage.

Native seeds are a finite resource, and their inclusion in revegetation is vital for supporting restoration outcomes that are both effective and scalable. Pelletized seed enhancement technologies (SETs) offer a promising solution to improve seed use efficiency in ecological restoration. Yet, knowledge of how diverse suites of native species perform when pelletized is required to optimize the application of SETs to the many species and ecosystems where restoration is required. Using a greenhouse trial of 64 Australian plant species, we assessed species performance to pelleting by evaluating (1) overall species amenability to pelleting based on total emergence and survival and (2) how pelleting modifies the rate of emergence based on average time to emergence, emergence rate index, and time spread of emergence. We investigated the potential for using morphological seed traits (seed endosperm:seed ratio, seed length, seed area, and seed coat thickness) to predict performance outcomes, by identifying traits that may aid in the prediction of species amenability to pelleting and emergence speed when pelletized. We found that some species demonstrate high amenability to pelleting and that pelleting can modify the emergence rates for many species. This work advances our understanding of the applicability of SETs for diverse native species, demonstrating the application of such technologies for meeting ecological restoration goals.

Climate change risk assessments are essential for the successful conservation and management of species under future climates. However, many management plans fail to include such assessments when evaluating threats to species or ecological communities. Species distribution models (SDMs) are versatile tools that can estimate species exposure to shifts in climate, but they lack information on the response capacity of species to climate change. Functional traits can be used in conjunction with SDMs to understand aspects of species biology that would suggest sensitivity to climate change. We illustrate how exposure to climate change and sensitivity of species based on their traits can be combined to generate predictions of climate change risk in four species listed as threatened (under state and federal legislation) and four unlisted plant species from the endemic Australian genus Persoonia (Proteaceae). We develop distribution models for each species using two emissions scenarios and assess four traits and two range metrics that are recognized as limiting factors in four potential climate change responses (reproduction, movement capability, habitat specialization, and spatial coverage) to assess the sensitivity of these eight species to climate change. Listed and unlisted species varied in niche breadth, environmental envelopes, and the percent contribution of variables to the model building process. Our models project a significant decline in habitat suitability under future climates at current occurrence locations for all species, and a 32–95% reduction in the total area (km2) of suitable habitat for all species by 2060, with significantly greater decline under the higher emissions scenario. Seven out of the eight species assessed ranked high for overall climate sensitivity therefore listing status may be a poor indicator of climate change risk to plant species. This has important implications for the continued focus on threatened taxa in conservation planning, particularly for hyper-diverse groups like plants and invertebrates where a species listing status is influenced by an often-slow progress towards comprehensive assessments of threat status.