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Background and Aims European ancient woodlands are subject to land use change, and the distribution of herbaceous understorey species may be threatened because of their poor ability to colonize isolated forest patches. The regeneration niche can determine the species assembly of a community, and seed germination traits may be important descriptors of this niche. Methods We analysed ecological records for 208 herbaceous species regarded as indicators of ancient woodlands in Europe and, where possible, collated data on seed germination traits, reviewed plant regeneration strategies and measured seed internal morphology traits. The relationship between plant regeneration strategies and ecological requirements was explored for 57 species using ordination and classification analysis. Key Results Three regeneration strategies were identified. Species growing in closed-canopy areas tend to have morphological seed dormancy, often requiring darkness and low temperatures for germination, and their shoots emerge in early spring, thus avoiding the competition for light from canopy species. These species are separated into two groups: autumn and late winter germinators. The third strategy is defined by open-forest plants with a preference for gaps, forest edges and riparian forests. They tend to have physiological seed dormancy and germinate in light and at higher temperatures, so their seedlings emerge in spring or summer. Conclusion Seed germination traits are fundamental to which species are good or poor colonizers of the temperate forest understorey and could provide a finer explanation than adult plant traits of species distribution patterns. Seed dormancy type, temperature stratification and light requirements for seed germination are important drivers of forest floor colonization patterns and should be taken in account when planning successful ecological recovery of temperate woodland understories. [ABSTRACT FROM AUTHOR]

With the need to meet ambitious restoration targets, an improved native seed sector for the production of herbaceous species with a practical and supportive policy framework is recognized. We evaluated the current “ready‐made” policy frameworks in Europe regarding the native seed supply of herbaceous species and found them to be, generally, unsatisfactory for both producers and users. Initially, such policies were designed for fodder seed and relate to distinctness, uniformity, and stability, traits that do not reflect the genetic heterogeneity of native species required for ecological restoration. Until recently, more suitable certification standards were designed to multiply fodder seed for preservation of the natural environment; however, due to the disparateness of the seed market in Europe, this policy is rarely practical and fails to encompass all herbaceous native species often resulting in unregulated seed sales. We recommend a new or adapted native seed policy constructed through a participatory or bottom‐up approach and supported through the formation of widely based trade associations. Such a policy could stimulate the native seed trade with concomitant impacts on the speed of improving ecosystem services. [ABSTRACT FROM AUTHOR]

The geographical distribution of existing populations of horse chestnut ( Aesculus hippocastanum L.) in Europe is determined by past demographic events during the Quaternary. In the present study we evaluate the imprints that northward expansions originated from common ancestry at southern Europe may have left on the present patterns of genetic variation for horse chestnut across the continent. Genetic diversity and levels of population structure in a European south-north gradient, ranging from the Balkans to the Scandinavian Peninsula, were determined with Amplified Fragment Length Polymorphism (AFLP) markers in 159 loci. A family of rarefaction techniques for the estimation of gene diversity was used to exclude potential confounding effects as a result of the unequal sample sizes. The results indicate that northern populations are not more genetically depleted than southern populations, thus suggesting that diversity for this species is not correlated with latitudinal distribution. Detailed hypotheses based on prediction models for different historical events associated with human-mediated spread of cultivation are examined for a better understanding of the current genetic patterns of regional differentiation. [ABSTRACT FROM AUTHOR]

The effects of fruit maturity, at the time of natural dispersal, on subsequent desiccation tolerance and sub-zero storage was investigated in three lots of Acer pseudoplatanus (sycamore) collected from northern to southern Europe. Fruits from the native plant distribution range in Italy had significantly higher desiccation tolerance (0.16 g water per g DW) than those from England (0.30) and Norway (0.50), confirming that the maximum potential desiccation tolerance in sycamore exceeds that of the recalcitrant type. In contrast, the unfrozen water content varied only slightly between seedlots, but systematically reduced with development (0.35 to 0.27 g water per g DW). Maximum survival (60 percent fruit germination) of seven days sub-zero temperature storage coincided with drying the Italian fruit lot to c. 0.2 g water per g DW followed by holding at -20 degree C, above the onset temperature for freezing, or at -196 degree C (liquid nitrogen). Fruit survival was much lower in the Italian fruits when held at this water content and -70 degree C, and in all other combinations of water content, temperature and fruit lot provenance. As the risk of nucleation in partially dried fruits held at -20 degree C is high, we recommend sycamore fruits are cryopreserved for long-term conservation.