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Collection of plants and seeds from wild populations threatens a large number of cycad species. We investigated to what extent individual life history stages contribute to population growth (λ) and compared two species with major differences in life histories in the African genus Encephalartos: Encephalartos cycadifolius, a highly persistent grassland species that resprouts after fire, and Encephalartos villosus, a relatively fast growing, non-sprouting forest species. Several harvesting scenarios impacting different sized individuals were simulated to determine the sensitivity of the two functional types to harvesting. In both species λ was most sensitive to changes in abundance of adult plants. The harvesting of seeds had minimal impact on population growth rates, whereas harvesting of adult plants led to rapid population decline. This response from two very different functional types suggests that the conservation of adult plants is critical for all cycad species. Despite similar responses to adult mortality, the two species had substantially different population growth rates. This determined recovery time after harvesting of adult individuals. Encephalartos cycadifolius is typical of highly persistent plant species associated with low levels of recruitment and unable to recover from even small losses of adults within a reasonable conservation time frame (<100 years). Our results suggest that the ability to recover from loss of individuals is an important factor that should be considered when assessing the vulnerability of wild populations to threats. [Copyright &y& Elsevier]

• We estimated the age of four geoxylic taxa by 14C dating B. insignis, C. laureola, P. simplex and T. kraussiana xylopodia. • The relatively medium to large xylopodia of all forbs tested were older than a decade, and up to five decades old. • Xylopodia showed no ring structure or unclear structures only visible at 7X magnification, which did not match 14C dates. • We recommend Radiocarbon dating using AMS, with sample treatment improvements, to calculate geoxyle age. Annual growth rings are absent in many long-lived grassland geoxyles. Thus, estimates of age for individuals are largely based on non-benchmarked assessments by experienced botanists. We wished to obtain a more precise estimate of age from the xylopodia of four geoxylic taxa (i.e. Berkheya insignis, Callilepis laureola, Protea simplex and Tephrosia kraussiana) growing in a Pondoland grassland, using both the gas proportional counting and Accelerated Mass Spectroscopy radiocarbon dating techniques. Plants sampled in 2008 fell within modern concentrations of carbon 14; therefore, radiocarbon dating generally yielded two ages for each plant, an older age (range: 45–51 years, mean=49, CV=3.6%) corresponding with the nuclear testing period, and a younger age (range: 10–29 years, mean=18, CV=35%), corresponding to the period after the Partial Nuclear Test Ban Treaty. Hence the older ages are much less variable than the younger ages. All plants had the older age estimate, and all but two had the younger age estimate. In addition, two plants each, had two similar older age estimates. P. simplex plants were 16, 24, 27 and 29, or 45, 46–49, 47 and 49 years, T. kraussiana 13, 15 and 16, or 50 and two of 51 years, C. laureola 12, 15 and 21, or 49–50 and two of 50 years and B. insignis were 10, or 49, 50 and 51 years old. Growth rings were not visible with the naked eye. However, using stereomicroscopy, ring-like patterns were visible to some extent at 7X magnification for B. insignis, P. simplex and T. kraussiana , but not C. laureola. Counts of these structures were much lower than the younger 14C dates, and hence are unlikely to be annual rings. Despite the ambiguity of multiple ages, these estimates are a useful starting point or benchmark for future empirical investigations of age for forbs with no clear annual rings. Most studies have used radiocarbon dating to estimate the age of woody tree stem tissue, whereas this study is one of few to measure the age of below-ground modern tissues of South African forbs. Suggestions for further refinement during collection and processing of geophytic sample material are made based on lessons learned from this investigation. [ABSTRACT FROM AUTHOR]

Despite its recognition as an important global resource for conservation, the International Union for Conservation of Nature's (IUCN) Red List of Threatened Species only provides assessments of extinction risk for a small and biased subset of known biodiversity. A more complete Red List can better support species-level conservation by indicating how quickly we need to act on species deemed to be priorities for conservation action. Vascular plants represent one of the Red List knowledge gaps, with only 7% of species currently on the Red List (including in the Data Deficient and Least Concern categories). Using vascular plants as a case study we highlight how recent developments, such as changes to rules, improvements to data management systems, better assessment tools and training, can support Red List assessment activity. We also identify ongoing challenges, such as the need to support regional and national assessment initiatives, the largely voluntary nature of the Red List community, as well as the need to meet core operating costs for the Red List. Finally, we highlight how new opportunities such as automation and batch uploading can fast-track assessments, and how better monitoring of assessment growth can help assess the impact of new developments. Most of our findings are also applicable to other species-rich groups that are under-represented on the Red List. We examine trends in plant Red Listing and conclude that the rate of new assessments has not increased in line with what would be required to reach goals such as the Barometer of Life. This may result partly from a lag between recent changes and their effects, but further progress can be made by realising the opportunities outlined here and by growing the Red List community and strengthening collaboration with IUCN. • The IUCN Red List, a key conservation resource, has incomplete and biased coverage. • Most known species have yet to be assessed and published on the Red List. • Rule changes and technical innovations may help scale up production of assessments • Current assessment rates are not sufficient to meet 2020 targets [ABSTRACT FROM AUTHOR]