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• Eleven new species are described. • New infraspecific combination created for I. pinnata. • All species illustrated in detailed photographic plates. • Conservation assessment and IUCN red list status is recommended for every species. Indigofera sect. Brachypodae DC. is a large group of approximately 40 species within the Cape Clade, mostly restricted to the Core Cape Region (CCR), with only two species extending eastwards to Grahamstown. This section has been subdivided into four subsections based primarily on morphological characters. Subsect. Brachypodae is the most diverse of the four subsections and is characterised by having sclerophyllous leaves, with a distinctly sunken midvein and (usually) revolute leaf margins. This group occurs almost exclusively within Fynbos, with a few species growing in coastal Strandveld vegetation. Revised here, nineteen species are recognized in this subsection, eleven of which are new to science. Additionally, a new infraspecific combination is created for I. pinnata following nomenclatural and identification confusion. All species are formally described here, with photographic plates of each and illustrations of corollas and calyces provided. Many of the new species were either unrecognised at the time of the last revision in Flora Capensis 2, or have only been discovered recently. Distribution maps and information regarding habitat preference, phenology, and ecology and recommended IUCN red list status of each species are also provided. [ABSTRACT FROM AUTHOR]

• Four Aspalathus species new to science are described. • Accounts are provided for three presumed extinct species that were rediscovered. • Detailed photographic plates and distribution maps are included. • Conservation assessments are provided for all seven species. We describe four new species from the Western Cape, South Africa. Aspalathus strigosa Du Preez & C.H.Stirt. is only known by the type collection from the southern slopes of the Klein Swartberg Mountains near Ladismith. Aspalathus albomagnifica Du Preez & C.H.Stirt. is a white-flowered species from lowland renosterveld and fynbos from Hartenbos on the Garden Route. Aspalathus jardinii Du Preez & C.H.Stirt. is a habitat specialist growing in sand dunes of the Riet River running through the Swartruggens Mountains. Aspalathus albicephala Du Preez & C.H.Stirt. is an attractive, critically endangered species from the rooibos belt on Gifberg Mountain. Notes are also provided on three recently rediscovered taxa that were believed to be extinct, Aspalathus cordicarpa R.Dahlgren, A. compacta R.Dahlgren and A. complicata (Benth.) R.Dahlgren. Composite photographic plates, distribution maps, details of habitat, ecology and conservation status are provided for all species. [ABSTRACT FROM AUTHOR]

• Four species new to science are described. • Detailed photographic plates and distribution maps are included. • Conservation assessments are provided for all four species. Four new Indigofera species are described from the Greater Cape Floristic Region (GCFR). Indigofera barkeri is a new annual from the Richtersveld, with small flowers, 3.5–4.0 mm long, pinnately trifoliolate leaves and laterally flattened seeds. Indigofera dodii is endemic to the area around Cape Town, growing on granite and shaly slopes. It has apically congested racemes, flowers 6.0–6.5 mm long, digitately trifoliolate leaves, fruit with a hispid indumentum and tuberculate seed testas. Indigofera gariepensis , endemic to dry riverbeds in the eastern Richtersveld, is recognized by its alternate, silky-velutinous leaflets and calyx lobes ± equal in length to its 5.5–6.5 mm long magenta flowers. Indigofera tanquana is known from only two collections and is endemic to the western Tanqua Karoo. It is easily recognized by its broad old grey stems, spinescent branches, simple grey-canescent leaves that aggregate on woody brachyblasts and reddish-magenta flowers. Detailed morphological descriptions are presented with composite photographic plates for each species. Notes on ecology, detailed diagnoses comparing with closely related species, a distribution map and an IUCN red list conservation assessment for each species is also provided. [ABSTRACT FROM AUTHOR]

• Erica glabella, Hippia frutescens and Salvia africana-lutea (methanol), and Eriocephalus racemosa (hexane) extracts IC 50 at < 30 µg/mL • Eriocephalus racemosa induced 21.48±2.86% apoptosis similar to cisplatin 23.72±4.36%. • Metabolite profiling of Salvia africana-lutea extract revealed the presence of phosphatidylcholines, triterpenoids, oxepane and 7-O-methylated flavonoids derivatives. Breast cancer is a leading cause of cancer-related deaths in women globally. Even though a plethora of treatments are available, most patients experience adverse effects which affect their quality of life. The aim of this study was to investigate the utility of nine Fynbos plants (Erica magnisylvae E.G.H Oliv., Erica canescens J.C. Wendl. , Erica coccinea L. , Erica glabella Thunb. , Erica corifolia L. , Eriocephalus racemosa L. , Hippia frutescens L., Salvia africana-lutea L. and an unknown Fynbos plant) in treating breast cancer. Solvent extraction of fynbos plants was performed, and crude extracts were evaluated against MDA-MB 231 cancer cell line to determine the cytotoxic activity with the mode of cell death confirmed using flow cytometry. Antioxidant activity and mass spectrometry-based metabolite profiling were performed to characterize and identify the phytochemical constituents of the extracts. The methanol extracts from E. glabella., H. frutescens and S. africana-lutea and the hexane extract from E. racemosa showed promising cytotoxic activities in the screening phase and thus were further evaluated to determine their 50% inhibitory concentrations (IC 50) which were found to be < 30 µg/mL. Flow cytometry analysis of treated MDA-MB 231 cells revealed promising results for the hexane crude extract (leaves) of E. racemosa and stem methanol crude extract of H. frutescens which induced apoptosis in MDA-MB-231 cancer cell line, similar to the reference drug cisplatin. Metabolite profiling of S. africana-lutea extract, the most potent apoptosis inducer in this study, revealed the presence of phosphatidylcholines, triterpenoids, oxepane and 7-O-methylated flavonoids derivatives. It was concluded that E. racemosa and S. africana-lutea are excellent candidates for further development of therapeutic agents in the fight against cancer, given the pressing need for novel efficacious agents. [ABSTRACT FROM AUTHOR]

• The alien Melaleuca rugulosa (Myrtaceae) has spread over 1.2 hectares in South Africa.. • The one invasive population is in pristine fynbos in Table Mountain National Park. • Recent fires most likely triggered the invasion of this serotinous species. • Melaleuca rugulosa can still be extirpated and should be listed as 1a under NEM:BA. Several Melaleuca (Myrtaceae) species are invasive globally. Recently an increase in invasive species from this genus have been reported in South Africa. Here we document the first detailed assessment of the distribution and invasive potential of Melaleuca rugulosa in South Africa. We assess population structure, determine the current and potential future distribution in South Africa using climatic variables, conduct a risk analysis, provide recommendations for management, and consider the feasibility of eradication. We found one naturalising population of ∼665 individuals covering more than 1.2 hectares. It was first recorded in 1961 invading the native fynbos vegetation in the Table Mountain National Park (TMNP). Two recent fires – in 2009 and 2016 – likely enhanced spread, this spread happened despite undocumented clearing attempts in the last decade. The south-western Cape is the most climatically suitable for M. rugulosa, with most other wetter areas of the country being only partly suitable regions. The risk analysis indicated a medium risk, and we suggest listing M. rugulosa as category 1a (eradication target) under the South African National Environmental Management: Biodiversity Act (10/ 2004). Given the small area occupied, ease of access and the lack of a soil seed bank, the population can be extirpated from Devil's Peak within the TMNP. We highlight that serotinous alien species, particular from the Myrtaceae, should receive more attention as potential invasive species in fire-driven ecosystems and that their lack of invasiveness in areas where fire is suppressed, should not be misinterpreted as being a low-risk species. [ABSTRACT FROM AUTHOR]

• The suitability of road verges as habitats for fynbos plants is poorly understood. • We investigate pollination of ornithophilous Erica glandulosa in road verges. • Fewer flowers were visited by birds closer to the road. • Fewer flowers were visited in road verges next to transformed land. • On average, 20–30% of flowers found within 10 m of the road were visited by birds. Road verges can provide important habitats for plants, especially in transformed landscapes. However, roads and their associated traffic have several adverse impacts on ecosystems that can disrupt vital ecological processes, including pollination. In transformed landscapes, the negative effects of roads on pollination might be complemented by impacts of large-scale habitat modification. In these landscapes, road verge populations of plants that rely on pollinators could thus be at risk of pollination failure. This study investigates the pollination of a reseeding, bird-pollinated shrub, Erica glandulosa , in road verges of a fragmented and transformed rural landscape in the southeastern Cape Floristic Region. We test for road impacts on pollination by comparing number of ruptured anther rings – a proxy for pollination – in fynbos vegetation fragments at different distances from the road (0–10, 20–30 and 40–50 m). We also test whether different land-cover types (intact fynbos, alien thickets and rangelands/pastures) next to road verges influence the number of ruptured anther rings. After controlling for robbing rate and plant density, fewer flowers were pollinated near the road (0–10 m) than farther away (beyond 20 m), and fewer flowers were pollinated where road verges occurred next to alien thickets or pastures/rangelands compared to intact fynbos. However, bird pollinators were not excluded in road verges: on average, ca. 20–30% of flowers occurring within 10 m of the road were still visited by birds. While we expect the reduced pollination rate to have a negative effect on the fecundity of road-verge plants, it remains to be tested whether the pollination rate observed in verges is sufficient to sustain populations of bird-pollinated, seed-dependent plants. [ABSTRACT FROM AUTHOR]

• Secondary invader species after alien tree clearing are seldom reported. • Secondary invader richness is lower in riparian Fynbos than non-riparian areas. • Secondary invaders are a mix of annuals and perennials (shrubs, herbs and graminoids). • Secondary invader richness persisted up to a decade after clearing. After the clearing of invasive alien plants, non-target alien species often move in. This is known as secondary invasion and these alien species can suppress native plant species' recovery. This is a global problem that has only recently received attention in South Africa. But whether secondary invaders in riparian areas have similar effects than those in more terrestrial areas is largely unknown globally and in South Africa. Therefore, here we ask which species and growth forms are associated with secondary invasion in riparian areas in the Fynbos biome, and secondly whether secondary invader species richness changes over time post clearing. We found 13 secondary invader species in a riparian area after clearing of alien invasive Eucalyptus trees. In the first year after clearing, there were only annuals, but thereafter it was a mix of annuals and perennials (shrubs, herbs, and graminoids). Secondary invader richness did not significantly differ with time after clearing, persisting even up to 10 years. In this riparian area, secondary invader species richness was much lower than that for non-riparian Fynbos areas. From this preliminary study we highlight the need for more research in understanding how secondary invaders influence restoration efforts and native species recovery in riparian systems. [ABSTRACT FROM AUTHOR]

• Secondary invader germination is not influenced by available soil nitrogen. • Elevated available soil nitrogen favours secondary invader growth. • Secondary invader species respond differently to available soil nitrogen. • Secondary invasion can be managed through a reduction in soil nitrogen levels. Invasive alien nitrogen-fixing species, such as Australian acacias, often leave a legacy of elevated available soil nitrogen after their removal. This legacy effect can facilitate secondary invasion by other alien species, thereby preventing natural restoration of areas being managed. To restore viable native plant communities in ecosystems where secondary invasion is a barrier to restoration, it is important to understand the soil legacy effects of invasions. Using Acacia saligna (Labill.) H. L. Wendl. (Fabaceae) invasions in the South African fynbos as case study, we determined (1) the extent to which levels of available soil nitrogen influence the germination and growth of secondary invaders; and (2) how this differs between secondary invader species. We chose five of the most common species that have been identified as secondary invaders after clearing invasive A. saligna in the Cape Flats Sand Fynbos: (i) Avena fatua (L.) (Poaceae), (ii) Briza maxima (L.) (Poaceae), (iii) Bromus diandrus (Roth.) (Poaceae), (iv) Hypochaeris radicata (L.) (Asteraceae), and (v) Raphanus raphanistrum (L.) (Brassicaceae). Using proportional fertigation, we created soil nitrate levels similar to those found in non-invaded areas (1mg/kg), and the lowest (3 mg/kg), median (7.5 mg/kg) and highest (12 mg/kg) levels typically found in areas previously invaded by A. saligna up to ten years after clearing. For each soil nitrate level, we germinated secondary invader seeds (five seeds per petri dish) in an incubator (five species × four soil nitrate levels × five replicates = 100 petri dishes). Furthermore, for each soil nitrate level, we grew secondary invaders (one plant per pot) in a greenhouse tunnel for five months (five species × four soil nitrate levels × five replicates = 100 pots). There was no significant relationship between germination success and soil nitrate level for any species. However, root and shoot dry mass were significantly positively correlated to soil nitrate level for all species. The relationship was nonetheless only linear for Bromus diandrus, Hypochaeris radicata , and Raphanus raphanistrum. These results indicate that the legacy of elevated available soil nitrogen does not have an effect on the germination of secondary invaders, but favours their growth. Therefore, secondary invasion can be managed through a reduction in soil nitrogen levels. However, secondary invader growth does not decrease at the same rate for all species in response to a decrease in available soil nitrogen. Thus, the use of soil nitrogen reduction as a tool for the management of secondary invasions should take into account the species being managed. However, given that multiple secondary invader species often dominate a restoration site, restoration efforts should reduce soil nitrogen to non-invaded levels to account for the different response rates to available soil nitrogen, and simply management efforts. [ABSTRACT FROM AUTHOR]

• In the 30–50-year absence of fire, thicket does not replace fynbos on all sites. • Fynbos persists on dune crests where it occupies a drier sites than thicket. • Fynbos shrubs are invading a dense turf, or grazing lawn adjacent to the coast. • Woody plant cover increased everywhere in the study area over the past three to five decades. • A shift in land use from subsistence agriculture to tourism most likely underpins these vegetation changes. It is hypothesized that in the Holocene dune fynbos-thicket mosaics of the Cape, decades-long absence of fire results in closed-canopy thicket replacing more open fynbos shrublands. We tested this hypothesis by analyzing repeat photographs from 16 sites at Cape St Francis in the south-eastern Cape Floristic Region. The period of monitoring ranged from 55 to 17 year and most sites had been last burnt between 30 and 50 years ago. We divided the sites into coastal (salt wind-exposed) and inland zones and computed, for each pair of photographs, the rate of change of four plant types, namely thicket shrubs, fynbos woody, fynbos herbaceous and grass. Coastal zone sites showed a significant increase in thicket shrub cover and a significant decline in both grass and fynbos herbaceous cover. Fynbos woody cover declined in the face of thicket invasion, but increased in grassy sites, most likely due to a decline in herbivory intensity. No significant changes in plant types were observed in the inland sites, although thicket shrub cover did increase marginally at the expense of fynbos woody plants. However, thicket invasion was restricted to swales and lower dune slopes; the dune fynbos of the upper slopes and crests remains uninvaded by thicket and surprisingly vigorous after 30–50 year without fire. This is consistent with the notion that fynbos species occupy drier sites than thicket in these dune landscapes and regular fire is not a prerequisite for its persistence. Overall, we showed a large increase in woody plant cover throughout the study area. While this pattern is consistent with predictions for vegetation change in response to atmospheric [CO2] pollution, it can also be explained by land use changes experienced in the study area, starting in the early 1960s, involving a shift from subsistence agriculture to holiday resort development and tourism. [ABSTRACT FROM AUTHOR]

• Resource allocation after 3 defoliation levels of Watsonia fourcadei plants was investigated. • Resource allocation patterns changed after 100% defoliation to favor survival of parent plants. • Sexual reproduction was only supported when surplus resources were available. • Allocation patterns of dry mass and nutrients was similar and p was probably limited in the habitat. • The reasons why Watsonia fourcadei plants follow " K' survival strategy are discussed. Geophytes are abundant in the Cape fynbos vegetation and many of the Cape geophytes , such as Watsonia species, flower mostly only in the first year after a fire. This study investigates the question if these plants have a resource allocation strategy which limits sexual reproduction to the post-fire environment and that they favor resource allocation to the storage organ for the survival of the parent plant at a cost to sexual reproduction. To test the hypothesis that the Cape geophyte Watsonia fourcadei represses sexual reproduction in favor of the survival of the parent plant, three levels of defoliation (20, 50 and 100%) were applied during a phenological stage when resources were least in the parent corms. Resource allocation to different plant parts was investigated when plants were in the seeding phase. Dry mass and nutrient (N, P. K, Ca, Mg and Ca) content were used as indicators of the resource allocation pattern. Dry mass and nutrient allocation patterns were similar, with significantly higher percentages of resources allocated to vegetative survival of the parent plant than to sexual reproductive organs (inflorescence and seeds) after complete defoliation, than after 20 and 50% defoliation. The W. fourcadei plants were able to accumulate adequate resources in the post-fire growth season to support sexual reproduction after up to 50% defoliation, albeit to a lesser extent than in control plants, but sexual reproduction was poorly supported after complete defoliation. Results indicate that W. fourcadei plants must be able to accumulate at least 3.5 g of dry mass in the new developing corm before resources are allocated to sexual reproductive plant parts. Replenishment of nutrient content after defoliation was not a limiting factor for resources allocation to sexual reproduction, except in the case of phosphate. W. fourcadei plants acted as a functional unit and resources allocation to sexual reproduction was controlled and depended on the availability of resources. None of the current resource allocation models are applicable to W. fourcadei and factors that could have selected for the apparent ' K ' survival strategy in this and other Cape geophyte species are discussed. [ABSTRACT FROM AUTHOR]

• Active sowing results in successful establishment of native shrub cover and diversity. • Pre-treatment of seed can improve success of a restoration sowing intervention. • Passive restoration is seed limited, suggesting a biotic threshold has been crossed. • Invasive plant seedbanks are not more effectively depleted by burning after clearing. • A decision tree has been developed to determine best protocols for restoration based on site-specific characteristics. Invasive alien plants negatively impact ecosystems, but recovery of native vegetation may fail following standard methods of alien species removal alone. Alternative management actions may thus be required. Cape Flats Sand Fynbos is a critically endangered vegetation type in the Cape Floristic Region of South Africa which is threatened by Acacia saligna invasion, but standard clearing methods have failed to restore native vegetation structure. A restoration study was performed comparing passive treatments i.e. clearing without burning (stack-block) versus clearing and burning (burn-block), as well as active intervention by sowing seeds of native species, either initially after burning or a year later, in which seeds were either not pre-treated or pre-treated with smoke and heat exposure before sowing. After two years all treatments resulted in different recovery trajectories, although none resembled the reference condition. Clearing without burning facilitated recovery in less degraded areas with higher initial native shrub cover, but otherwise resulted in limited vegetation recovery. Limited recovery facilitated secondary invasion by herbaceous weeds. Active seed sowing resulted in the highest recovery of native shrub cover and diversity. These findings suggest that passive restoration is constrained by seed limitation, due to the lack of recovery of vegetation components under passive clearing treatment. Active sowing was able to partially overcome this constraint through improved recovery of total shrub cover. However, non-sprouting shrub cover was higher while resprouting shrubs and species of Restionaceae were lower compared to the reference condition. Pre-treatment of seeds before sowing improved establishment of some species. Active treatment involving sowing pre-treated seeds after clearing and burning therefore resulted in best fynbos recovery compared to either of the passive treatments tested. A decision tree has been developed based on these findings in order to guide best protocol for managers. [ABSTRACT FROM AUTHOR]

• Flowering response of Watsonia fourcadei after slashing and burning treatments is quantified. • Flowering stimulus of several fynbos geophytes is not due to fire associated factors per se. • Mass flowering and seed set saturated pre-dispersal seed predation by seed weevils. • Some hypotheses for the fire stimulated flowering of Cape geophytes are rejected. • Post fire flowering is due to seed predator saturation and seedling requirement for an open seed bed. The often mass flowering of Watsonia and other geophyte species in the first year after a fire in the South African fynbos vegetation is well known, but it has rarely been quantified. Many fynbos geophytes also flower after the fynbos canopy was physically removed, but these flowering responses have also not been quantified. A study comparing the flowering response of geophytes after physical removal versus fire removal of the fynbos canopy was conducted to establish to what degree these species are fire dependant. It was also done to improve our understanding of fynbos geophyte ecology, especially towards establishing if the flowering response of these plants is due to fire related factors per se , or not. Vegetative growth, flowering response, seed set and seedling establishment of Watsonia fourcadei were recorded after two treatments, burning and physical removal of vegetation (slashing) in two veld ages (5- and 16 years). Responses of other co-occurring geophytic species to these treatments were also recorded. The number of vegetatively active W. fourcadei plants doubled and flowering percentage increased from 2.3% to 38.7% in the first year after the fire. In the second year after the fire the number of vegetatively active W. fourcadei plants was similar to those in the first year after the fire, but flowering percentage decreased to pre-fire levels. About 50% of W. fourcadei plants were dormant 5 years after the fire and > 90% were dormant in 16-year old fynbos. Flowering percentages of W. fourcadei in slashed 5-year old fynbos did not differ significantly from burned 16-year old fynbos. The flowering stimulus of W. fourcadei was thus not due to fire associated factors per se. Seed predation of W. fourcadei seed capsules decreased from 46.9% before the fire to 7.1% after the fire. Number of viable seed released increased from 15.8 seed mˉ² pre-fire to 1170.5 seed mˉ² post-fire and 233.1 seedlings mˉ² established after the fire. The 74-fold increase in seed release in the burned fynbos could not be ascribed to higher cross pollination success as about 40% of the flowers were autogamous. The number of vegetatively active geophytic species increased from 2.3 species mˉ² pre-fire to 7.9 species mˉ² post-fire in 16-year old burned fynbos and 4.0 species mˉ² in the slashed fynbos. Most (76%) of these geophytic species flowered after the fynbos was burned and 24% of the species flowered in the slashed fynbos. Only some of the geophytic species were thus dependent on fire to stimulate flowering. A repeated short cycle disturbance regime (ca. 5 years) of burning and/or slashing may result in a super-abundance of Watsonia plants that can displace smaller geophytic species. Previous hypotheses on proximate reasons for the Watsonia post-fire flowering that are rejected are: (i) greater visibility of the plants; (ii) heating of the soil and corms by fire and; (iii) increased availability of phosphorous and/or other minerals in the post-fire environment. Smoke as a factor to induce flowering in W. fourcadei growing under natural conditions is questioned. [ABSTRACT FROM AUTHOR]

• Anabolic/catabolic index greater in sites invaded by invasive alien species. • Boron and phosphorus related to tree invasion, supporting the Catabolic Theory. • Boron poverty constrains anabolism and hence tree establishment. • Phosphorous enrichment promotes catabolism and hence non-tree species. Invasion by invasive alien trees is a major threat to the biodiversity of the fynbos biome in South Africa. The environmental factors influencing the intensity of invasion are, however, largely unknown. In particular, the effects of soil nutrients on the invasion of alien trees in the fynbos biome have not been investigated. The Catabolic Theory predicts that trees will be more competitive than shrubs and herbaceous plants where anabolic nutrients (e.g. Mg, Mn and B) are comparatively more abundant than catabolic nutrients (e.g. P, Cu and Zn). We tested this theory at seven study sites by comparing soil nutrient concentrations in non-invaded and adjacent invaded sub-sites. Soil samples from 275 plots across 17 sub-sites were analysed for pH, Na, Mg, K, Ca, P, S, C, B, Mn, Cu and Zn. The results corroborated the Catabolic Theory. An index of anabolic to catabolic nutrients was greater in all ten sub-sites invaded by invasive alien trees than in sub-sites without invasion. Nutrients strongly related to tree invasion included B and P. As per the Catabolic Theory, poverty of B at certain sites is likely to constrain anabolism and consequently tree establishment. Some non-invaded sites had B concentrations of 0.02 mg kg−1, which is an order of magnitude less than critical deficiency thresholds in an agronomic context. By contrast, richness of P (as a result of prior fertilization) in fallow agricultural fields would, as per the Catabolic Theory, promote catabolism and the competitive strength of shrubs and/or herbaceous plants relative to trees. Practical implications of these findings include: 1) the mapping of soil properties such as B and P to reveal the inherent propensity of landscapes in the Western Cape to be invaded by trees; and 2) the application of B-binding substances such as illite and vermiculite to constrain invasion of trees in fynbos. [ABSTRACT FROM AUTHOR]

This study investigates the population structure and life history traits of the Critically Endangered cycad, Encephalartos latifrons. Populations of E. latifrons have been considered functionally extinct because no natural recruitment has been observed in the wild for almost 30 years. The discovery of a previously undocumented population of E. latifrons has made it possible to build on previous research into the life history and regeneration capabilities of the species. This new population was censused annually over 5 years; between 2013 and 2017. Population characteristics of this 'new' population were compared to earlier studies in 2010 of a well-known and intensively managed population. Results of the censuses show that the newly discovered population of E. latifrons appears to be increasing under current environmental conditions through natural recruitment. The discovery of a 'new' E. latifrons population has uncovered many more questions and further research is needed. Information on the life history of E. latifrons , particularly its response to fire, should be used to inform conservation management decisions at a time where the impact of climate change is predicted to have a major influence in the Fynbos Biome. • At least one wild Encephalartos latifrons population is capable of natural recruitment. • At least one E. latifrons population is increasing under present environmental conditions. • Plants in the seedling stage experience the highest levels of mortality. • Of the reproductive individuals present in the population, females outnumbered males. • All stages were significantly clustered in their spatial pattern. [ABSTRACT FROM AUTHOR]

It is often assumed that clearing invasive alien species will lead to the dissipation of their negative impacts and recovery of native plant diversity. However, this is often not the case because clearing of primary invasive alien species can lead to secondary invasion by non-target species. We investigated the effects of vegetation type and application of fire during management of biomass after clearing invasive acacias on secondary invasion in the South African fynbos. Furthermore, we determined how these effects change with years after clearing. We sampled vegetation in lowland and mountain fynbos cleared of invasive Acacia saligna using the "fell, stack and burn" method. During burning of the stacked slash, the area at the centre of the stack experiences a high severity fire while the area at the edge experiences a low severity fire. After fire, burn scars remain in place of the stacked slash. We sampled in and outside of 80 burn scars over three years after clearing. Overall, we set out to (1) identify species that are secondary invaders; (2) determine whether secondary invader richness and cover differ between where there were high and low severity fires and no fires, and how these differences change with years after clearing; and (3) determine whether secondary invader richness and cover differ in and between lowland and mountain fynbos, and how these differences change with years after clearing. We identified 32 secondary invader species. Mean secondary invader richness was lower where there were high severity fires (2.75) compared to where there were low severity fires (3.28) and no fires (3.24). Mean secondary invader proportion cover was lower where there were no fires (0.14) compared to where there were high severity fires (0.19) and low severity fires (0.2). Three years after clearing, secondary invader richness and cover had not changed or was now higher than in the first year, while secondary invader richness was similar between lowland and mountain fynbos. Secondary invader cover was similar between lowland and mountain fynbos up to two years after clearing but was 58% lower in lowland fynbos in the third year. Fire application after clearing invasive acacias can have positive (i.e. reduction of Acacia soil seed banks by triggering mass germination) and negative (i.e. favors the dominance of secondary invaders) effects. As a result, slash should be spread throughout the restoration site instead of being stacked and then burnt to reduce Acacia soil seed banks. To avoid the establishment of a second generation of invasive acacias, the seedlings that germinate can be controlled through manual weeding, mowing and herbicide application. Due to the persistence and abundance of secondary invaders up to three years after clearing at levels similar to or higher than in the first year, we conclude that practicing restoration ecologists must manage these species to ensure successful restoration of native plant diversity. • After alien clearing in the fynbos, we found 32 secondary invader species. • High severity fires after alien clearing reduce secondary invader richness. • Fire application after alien clearing increases secondary invader cover. • Secondary invasion persists up to three years after alien clearing. [ABSTRACT FROM AUTHOR]

Abstract The lack of examples of hybridisation within South African Cape Fynbos lineages gives the impression that interspecific hybridisation events may be rare in this system. If this is the case, then long-distance translocations of plant species across the Cape are unlikely to have any impact on the genetic component of biodiversity. Here we demonstrate that local populations of Protea eximia have hybridised with the non-local and introduced Protea susannae at Van Stadens Wildflower Reserve using morphological and genetic data; DNA sequence data were obtained from the internal transcribed spacer from the nuclear ribosomal cistron and a noncoding region of the chloroplast. Of the 24 plants from the reserve that were analysed, 11 were identified as hybrids, and comparing nuclear and chloroplast signals indicated bidirectional gene-flow between these species. This is the first study demonstrating the potential threat of long-distance dispersal in a Cape lineage to the genetic integrity of local populations. Highlights • Hybridisation is considered to be rare within Cape lineages. • We detected hybrids between local Protea eximia and introduced P. susannae. • Hybrids were common and widespread in the Van Stadens Wildflower Reserve. • Translocations may result in unexpected hybridisation. • This may represent a risk to the genetic integrity of local populations and species. [ABSTRACT FROM AUTHOR]

Pine plantations and pine invasions have numerous impacts on native ecosystems in the Fynbos biome of South Africa. The severity of these impacts greatly determines the extent of potential ecosystem recovery after the pines are felled. The recovery potential of fynbos after felling of pine plantations of varying longevity and the subsequent application of ecological burns was investigated in the Helderberg Nature Reserve, Western Cape Province, South Africa. Above-ground vegetation, soil seed bank and abiotic variables were sampled across three treatments (reference fynbos and sites that had been under pines for 30 and 50 years respectively) using 1 m 2 quadrats placed along 50 m line transects. The soil seed bank samples were smoke treated and then monitored in a greenhouse to determine the soil seed bank species and growth form composition. Areas previously under 30 year old pine plantations had high native species and growth form density (number of species/growth forms per unit area) and similar plant density (number of individuals per unit area) to the reference fynbos areas. Conversely, areas previously under 50 year old pine plantations had significantly lower native species and growth form density and plant density than the reference fynbos and were dominated by alien species. In addition, areas previously under 50 year old pine plantations had lower species diversity than the reference fynbos areas and areas previously under 30 year old pine plantations which were found to be similar to one another. Felled pine plantations were shown to minimally impact on soil abiotic variables, with only soil temperature and pH showing significant differences. Therefore, areas previously under 30 year old pine plantations have higher recovery potential following pine removal than 50 year old plantations, owing to the depleted native soil seed bank in the latter. Consequently, active restoration may be needed to re-introduce the missing long-lived growth forms and to prevent soil erosion. Pine plantation and invasion management in the Fynbos biome should aim to fell pines before the native seed bank is depleted to maintain the recovery potential of fynbos and prevent the need for active restoration. [ABSTRACT FROM AUTHOR]

Ambiguous species delimitations and nomenclature are a major impediment for users of biodiversity information. This is more pronounced in plant lineages that have experienced recent and rapid diversification or where there is a tendency to lump many species under a general name. The papilionoid genus Psoralea L. is a young lineage (Pliocene, ca. 75 species) which has diversified rapidly within the South African fynbos biome and adjacent habitats. All species bearing 5–19 foliolate leaves were previously often lumped within the polymorphic species Psoralea pinnata , resulting in an unwieldy complex of at least 28 taxa, of which only eleven species are formally named. In this study we analyzed live specimens and populations in the field and herbarium collections, capturing their morphological and geographic diversity, for species delimitation. The results support the recognition of 25 distinct species, of which 14 are described here as new: P. azuroides ; P. brilliantissima ; P. elegans ; P. floccosa ; P. imminens ; P. intonsa ; P. ivumba ; P. kougaensis ; P. montana ; P. muirii ; P. rhizotoma ; P. semota ; P. sordida ; and P. suaveolens . The taxon P. pinnata var. latifolia Harv. is raised to species rank, as P. latifolia comb. nov. The name P. pinnata sensu stricto is restricted here to a taxon with 5–9-leaflets extending from the Cape Peninsula to the Kogelberg mountains. We provide a key for the identification of all 25 species along with full descriptions, distribution maps and notes on their conservation status. [ABSTRACT FROM AUTHOR]

Seed mortality represents a substantial cost for plants and can have a large effect on plant reproductive fitness. Here we report evidence for pre-dispersal seed mortality by a novel mechanism: culm felling in female nut-seeded restios by rodents. We noted strong female-specific culm felling in the nut-fruited Cannomois congesta Mast. (Restionaceae) from the South Western Cape, South Africa. Camera-trap analysis showed that this culm felling is carried out by the striped mouse, Rhabdomys pumilio Spar. (Muridae) and is primarily aimed at obtaining ripe seeds held at the tips of female culms rather than eating the culm. All seeds acquired by R. pumilio were found to be consumed. We recorded a mean loss of 81% culms/seeds in affected female C. congesta plants in contrast to very few culm losses from males. This highly selective rodent behaviour is presumably due to detectable differences in the nutritional reward associated with terminal male/female inflorescences (large nut-like seeds vs. pollen). Pre-dispersal seed predation through culm felling could significantly reduce the fecundity of ant-dispersed restios such as C. congesta because fewer seeds manage to fall to ground where mutualistic ground foraging ants compete with rodents for seeds. Culm losses through felling could also have physiological and nutritional implications. Future research should explore the generality of this phenomenon amongst the Restionaceae, and quantify the associated physiological and reproductive costs. [ABSTRACT FROM AUTHOR]

Rodents are important pollinators and seed predators of fynbos Proteaceae, but their role as florivores has received little attention. Chacma baboons ( Papio hamadryas ursinus ) are known to feed on Proteaceae inflorescences, however, their effect on plant reproduction has not been quantified. We recorded the extent of damage by rodents and baboons to inflorescences of the dominant shrub, Protea neriifolia , in 20 × 20 m plots in the Jonkershoek Nature Reserve near Stellenbosch. Damage was distributed patchily across the landscape. Rodents damaged up to 23% of the inflorescences per plot by feeding on styles and nectar. We observed the striped mouse ( Rhabdomys pumilio ) climbing up plants to feed on inflorescences. Up to 14% of inflorescences in some plots were destroyed by rodents gnawing through inflorescence stems. Baboons damaged or destroyed 12% to 29% of inflorescences at three study sites, but did not forage at all in the three remaining study sites. Among plant individuals affected by baboons or rodents, a mean proportion of 0.49 ± 0.31 (SD) of individuals' inflorescences were damaged or destroyed. Florivory by rodents and baboons can thus reduce the fecundity of P. neriifolia significantly. Protea inflorescences may be an important seasonal food source for certain rodents. In an evolutionary context, rodent florivory may have been an important selective force that caused certain Proteaceae species to shift to rodent pollination. Further work is needed to determine which rodent species feed on Protea inflorescences and whether rodent florivory is widespread in fynbos. [ABSTRACT FROM AUTHOR]

The causes and consequences of plant flammability are a contested issue. In fire-prone ecosystems, high flammability is invoked as a trait (in combination with fire-survival traits) that enhances reproductive success and reduces competition in the post-fire environment. On the other hand, flammability may be a consequence of other selective forces, for example, deterring herbivores. Here, we use a standardised method for estimating the flammabilities of 99 species distributed across five biomes in a small area of the southwestern Cape Floristic Region, South Africa. The fire-prone Fynbos and Grassland biomes included many highly flammable species, notably among graminoids and small-leaved shrubs with densely packed, fine twigs. However, Fynbos included many weakly flammable species. In the fire-free biomes (Forest, Nama-Karoo and Thicket), most species had low flammability, especially succulents. However, flammable species also occurred in all three biomes, including species with traits normally attributed to non-flammable species (e.g. large leaves sparsely arranged on coarse twigs). Since these biomes are fire-free, flammability in these species cannot be attributed to a fire-related selective regime. [ABSTRACT FROM AUTHOR]

Landscapes of the eastern Cape Floristic Region are extremely rich in biomes. Analysis of the determinants of boundaries between biomes can generate insights and predictions that are useful for the applied ecological sciences. Here we used a historical data set and multivariate methods to explore the determinants of the boundaries of Forest, Fynbos, Grassland, Renosterveld and Thicket biomes in a 1200 km 2 area of the Kouga region. The data set comprised 203 (10 m × 10 m) sites with corresponding landscape-scale environmental variables, and 100 sites with corresponding site-bound edaphic (physical and chemical) variables. Of the landscape variables, soil drainage and fire exposure had the strongest biome-specific associations: most Grassland occurred on seasonally waterlogged soils and Renosterveld on moderately drained soils. While Forest was exclusively associated with landscapes protected from fire, much Fynbos and Thicket were found in areas exposed to fires of intermediate frequency; however, in these situations Fynbos is restricted to sandstone-derived soils and thicket to shale-derived soils. Other strong patterns were the restriction of Forest to sandstone-derived soils and of Thicket to soils of deep to intermediate depth. Soils of the majority of Fynbos and Grassland were shallow, rocky and infertile, while those of Forest and Thicket were deep, rock-free and fertile, especially in terms of oxidizable carbon and total nitrogen. The relatively high fertility of Forest and Thicket soils is attributed canopy-induced enrichment in the prolonged absence of fire. Renosterveld occupied soils of intermediate fertility. These patterns can provide useful insights for developing experimental approached to simultaneously assess the determinants of multiple boundaries in the biome-rich landscape of the eastern Cape Floristic Region. [ABSTRACT FROM AUTHOR]

We ask two questions concerning the creation and maintenance of boundaries between forest and fynbos biomes in the southern Cape, South Africa: 1) is the presence of forest vegetation constrained to nutrient-rich soils? and 2) do plant traits (specific leaf area, leaf area, leaf dry matter content, leaf nutrients) reflect underlying soil nutrient status? At seven paired sites where forest and fynbos occur adjacent to each other with identical geology and position in the landscape, we tested whether forest soils had a different nutrient status to that of fynbos soils. At three of these sites we measured a suite of plant traits and tested whether these traits were correlated with soil characteristics. The paired site comparisons found that forest soils had a higher nutrient status and higher soil C:N ratios than the fynbos soils. Nonetheless, when compared across sites many forest soils had a nutrient status that was equivalent or lower than some fynbos soils. In addition, the forest soils at our study sites are still relatively nutrient-poor when compared to those of other temperate ecosystems. Although fynbos vegetation had traits that confer higher nutrient use efficiency than forest, both forest and fynbos species seem to have traits that confer conservative resource strategies (e.g., low leaf N and high leaf dry matter content). We suggest that both fynbos and afrotemperate forest are dominated by communities that are adapted to nutrient-poor conditions, and that the increase in nutrient status observed in forest soils is driven by niche construction. [ABSTRACT FROM AUTHOR]

Wild fire is an important disturbance that shapes global biome distributions and maintains the structure, function and biological diversity of plant communities in fire-prone environments. Physical, chemical and architectural properties of plants are known to affect flammability. We wished to explore how these traits contribute to fire properties at the individual species level and how flammability varies with other plant traits, including recruitment strategy. We studied flammability and traits that contribute to it in 29 woody species occurring in fynbos and renosterveld shrublands in the Cape region of South Africa. Fifteen of the species had fire-stimulated recruitment and 14 recruit in unburnt, older vegetation. Flammability was measured on whole plants or large shoots with intact architecture. Results across all species were consistent with other studies in finding that the proportions of dead and fine fuel are good predictors of flammability. Significantly higher flame temperatures and proportions of sample units burnt were recorded for fire-stimulated vs. non-fire-stimulated recruiters. These differences were associated with significant differences in the dead fuel proportion and fuel bed porosity between recruitment strategies. This is consistent with the hypothesis that flammability is most likely to be selected for in species that are the first to occupy post-burn gaps, where a combination of increased flammability and recruitment success enhances their fitness in the fire-prone environment. [ABSTRACT FROM AUTHOR]

The distribution of South African biomes is expected to be drastically altered as a result of climatic change and increasing atmospheric CO 2 in the 21st century. Developing the capacity to anticipate change is of critical importance if we are to mitigate and efficiently adapt to the reorganization of South African vegetation cover. Dynamic Vegetation Models (DVMs) simulate the distribution and functioning of plant functional types (PFTs) and their interactions. Outputs include biome distribution maps, assessments of carbon cycling and the quantification of plant productivity, all of which can be produced for past, present and future conditions. DVMs were originally conceived of as analogs to general circulation models (GCMs) and applied globally, but to be unbiased globally necessitates choosing parameters and representing processes that may not be regionally appropriate. Models populated with a modified suite of PFTs and parameterized appropriately for local conditions are better suited to studies concerned with vegetation dynamics and global change impacts at the country or continent-scale. In their current form DGVMs do not include the plant types and key processes of many South African biomes. Therefore, while projections of global change impacts are available for biomes dominated by forest trees, savanna trees and grasses, little can be learned about some of our most biodiverse and threatened biomes, particularly the Fynbos and Thicket biomes, and the Succulent Karoo. We outline the limitations of existing DVMs and improvements required before reliable projections of global change impacts on South African biomes can be produced. Reparameterization of some PFTs and fire models could easily be achieved, and would lead to large improvements in model simulations. However, there remain numerous processes and facets of the ecology of South African vegetation that will limit the applicability of DVMs in their current form. [ABSTRACT FROM AUTHOR]

Nutrient inputs and dynamics of the fynbos ecosystem, particularly after a fire, are poorly understood. This article provides chemical analyses of macronutrients (Cl, Na, SO 4 , Mg, Ca and K) in rainwater, stream water, soil and bedrock over a period of one year following a fire event in a coastal mountain sandstone fynbos ecosystem. Rainwater, stream water, soil and bedrock samples were taken from a mountain fynbos area underlain by homogeneous Peninsula Formation sandstone bedrock for a one-year period. Rainwater, stream water and soil saturated paste extracts were analysed for macronutrients using a Dionex DX-120 Ion Chromatograph. Crushed soil and bedrock samples were analysed for major element oxide and S content. Above-ground biomass recovery after one year was modest (5–10% of the 19-year-old pre-fire biomass) with marine aerosols supplying Cl and Na ions to the ecosystem and a significant amount of Mg, SO 4 , Ca and K. Additional Mg, SO 4 , Ca and K are supplied by deposition of local and regional fire ash and dust (mineral aerosols) transported from inland sources mostly by northwesterly winter winds. Nutrient loss diminishes rapidly with the return of pre-fire stream values within 9 months after fire, with nutrients gradually replaced through atmospheric deposition rather than the slow weathering bedrock. Macronutrients supplied to the study area reflect seasonal differences with atmospheric processes being the primary source of nutrients to the ecosystem. [ABSTRACT FROM AUTHOR]

Seed storage under appropriate conditions is a relatively inexpensive means of safeguarding plant genetic material for ex situ conservation. Post-storage germination trials are used to determine the viability of stored seeds, and hence the efficacy of the particular storage treatment. Kumara plicatilis (= Aloe plicatilis ) is a tree aloe endemic to mountain fynbos in the Boland, south-western Cape. The viability and germination behaviour of K. plicatilis seeds were assessed for seeds stored for four and nine months at − 80 °C, 4 °C, 25 °C and under ambient conditions in a laboratory. Seeds were germinated under controlled conditions and germination rates and percentages determined. Ungerminated seeds were tested for viability using tetrazolium salt. Seed viability was not significantly reduced during storage. Seeds stored at − 80 °C for four and nine months exhibited the fastest germination rate overall (both 5.9 ± 0.3 weeks, mean ± S.E.), and slowest was for seeds stored under ambient conditions for four and nine months (both 7.8 ± 0.4 weeks). All seed lots showed similar percentage germination after four months of storage (78.0–90.4%). The highest percentage germination overall was for seeds stored at − 80 °C for four months (90.4%) and the lowest was for seeds kept at 4 °C and − 80 °C for nine months (39.2 and 39.6%, respectively). Respective percentage viability for ungerminated seeds in these two treatments was 82% and 87%, respectively, indicating the induction of secondary dormancy. Induced dormancy triggered by protracted cold temperatures may be an adaptation that enables seeds to survive prolonged extreme conditions that are unfavourable for germination. Further research on the long-term storage of aloe seeds would be beneficial for developing long-term seed storage and germination testing protocols for ex situ conservation. [ABSTRACT FROM AUTHOR]

Wood anatomical data is presented for 29 southern African shrubby species representing eight genera ( Aspalathus , Calobota , Crotalaria , Leobordea , Lotononis , Rafnia , Wiborgia , Wiborgiella ) of the predominantly African tribe Crotalarieae (Fabaceae). The taxa examined share short vessel elements, exclusively simple perforation plates and vestured intervessel pits, i.e. the wood traits that are typical for many other genera of Papilionoideae. The loss of helical thickenings may be considered as a synapomorphy for Crotalarieae, with a reversal to this character state within Lotononis . Generally, the pattern of wood structure diversity within the Crotalarieae is related more to the growth habits of the plants and probably to environmental factors than to their taxonomy or phylogenetic relationships. All genera (except Crotalaria ) and practically all species studied showed diagonal to dendritic arrangement of vessel groups, up to their fusion into large dendritic aggregations in Calobota species from arid (non-fynbos) regions. Some species from karroid scrubs ( Calobota angustifolia , Calobota cytisoides ) and fynbos ( Aspalathus excelsa , Aspalathus linearis , Aspalathus nigra ) show no dendritic vessel pattern, however. The banded axial parenchyma appears independently in three lineages of Crotalarieae, i.e. in Aspalathus + Wiborgia + Wiborgiella , Rafnia , and in crown species of Calobota . Lotononis s.str. and Leobordea show unbranched or weakly branched coarse vestures in their intervessel pits, whereas other taxa examined share the presence of vestures, appearing as strongly branched fine protuberances. Micromorphological characters of vestured intervessel pits are likely to be useful for the systematics of Crotalarieae. [ABSTRACT FROM AUTHOR]

We present a simple method for assessing the medium-term sustainability of different flower harvesting intensities (i.e. percentage of number of stems harvested per individual) for two re-seeders and re-sprouters of fynbos plants on the Agulhas Plain in the Cape Floristic Region, South Africa. We interpret our results from an ecological point of view, looking at impacts of harvesting on vegetative re-growth and survival of frequently harvested fynbos species, and an economic point of view, determining the cumulative number of stems harvested per year. We analysed the impact of different harvesting intensities on two obligate re-seeding ( Erica corifolia (L.) and Erica imbricata (L.)) and two strongly re-sprouting species ( Brunia laevis (Thunb.) and Staavia radiata (L. Dahl)) on different flower farms. Seventy-five randomly selected plants of each species were experimentally harvested in the same way as is done by flower harvesters. Fifteen plants of each species were left as controls (un-harvested) and 15 each were harvested (cut 15–20 cm below the inflorescence) such that 25%, 50%, 75%, and 100% of the inflorescences were removed. Harvested stems were labelled and the number of new shoots counted. Additionally we recorded plant height and mortality. 100% harvesting resulted in high mortality rates for both re-seeders (for both species 100% of the individuals were dead at the end of the experiment) and resprouters (for one species all 15 individuals were dead at the end of the experiment and for the other species 4 of 15). Re-seeders in particular were highly susceptible to harvesting below the first branching node, which generally also resulted in plant death. Both guilds can survive up to 75% harvesting (resprouters experienced no mortality for one species, while in the other 4 out of 15 died; of the re-seeders, 9 out of 15 died in the one species, while only 1 out of 15 in the other) and are still able to grow in height. For both seeders and resprouters we recommend that flower harvesters do not harvest in young veld. To ensure sufficient seed set and to avoid seed bank depletion we recommend to preferably only harvest between 25 and 50% of stems per individual. [ABSTRACT FROM AUTHOR]

Abstract: The consumption and dispersal of seeds by rodents play an important role in the seed bank dynamics of many plant species. Seed dispersal versus consumption patterns may however vary seasonally with food availability. We investigated whether the fate of Leucadendron sessile seeds was seasonally variable, and whether it could be explained by food availability. First we established that the seeds of most non-serotinous, large-seeded plants were released in early summer. Then we monitored seed dispersal and consumption behaviour, primarily by the nocturnal seed caching and dispersing rodent, Acomys subspinosus over one year. To investigate seasonal fluctuations in the diet of A. subspinosus, we conducted regular faecal analyses of this rodent and compared them to those of Rhabdomys pumilio, a diurnal rodent which is known to consume seeds but not cache them. While the diet of R. pumilio does not appear to fluctuate greatly across seasons, the diet of A. subspinosus does. A. subspinosus changes its diet from an insect dominated diet in winter and spring to a diet with a strong seed component in summer and autumn. Corresponding to this dietary shift, A. subspinosus changes its primary foraging behaviour from seed consumption to seed burial. These results suggest that a plentiful bank of seeds in autumn encourages seed caching but that by winter, the seed bank is so depleted that A. subspinosus consumes whatever it finds until summer when the seed bank is replenished. Our results suggest that A. subspinosus seed dispersal and consumptive behaviour fluctuates during the year and this appears to be related to seed availability. This is likely to cause temporal fluctuations in the seed bank, and consequently the timing of fires will have strong effects on seed germination. [Copyright &y& Elsevier]

Abstract: Detailed wood anatomical data for 32 species from all nine genera of the tribe Podalyrieae are presented, together with numerical analyses and the mapping of character states onto the latest available molecular phylogeny. It was found that trees (Cadia, Calpurnia and Virgilia) have vessels in small isolated groups, whilst fynbos shrubs (the remaining genera: Amphithalea, Cyclopia, Liparia, Podalyria, Stirtonanthus and Xiphotheca) commonly show highly grouped narrow vessels (frequently in a dendritic pattern), and helical thickening on the vessel walls. Comparisons of the main character state changes with the molecular phylogeny of the tribe show that the wood structure of trees probably represents the basic condition in the tribe; character states present in shrubs appear to have arisen a few times and very likely represent adaptations to seasonal water stress. In general, the wood anatomy is congruent with current subtribal and generic delimitations. Fire-survival strategy is reflected in the rays, with seeders having mostly procumbent cells whilst sprouters have square and upright cells. The close similarity in wood anatomy between Cadia and Calpurnia is in agreement with the transfer of Cadia to the Podalyrieae. A remarkable diversity of crystals was found, including prismatic, acicular and navicular crystals, the last two of which may occur singly or in sheaf-like aggregates. [Copyright &y& Elsevier]

Abstract: The Silvertree (Leucadendron argenteum (L.) R.Br.) is an iconic tree to South Africans and tourists alike. This endangered species is endemic to the Cape Peninsula, the most southwestern part of Africa. Despite its visual presence, no population genetic data of L. argenteum are currently available, but such information is crucial for effective conservation management. A historical question is whether the inland populations are natural or planted? This study aimed to reveal the genetic structure and possible differences of L. argenteum populations on the Cape Peninsula and inland at Helderberg, Paarl Mountain and Simonsberg. It was expected that inland populations would exhibit reduced genetic variation due to their isolation from each other and the main Cape Peninsula gene pool. Furthermore, genetic differences between populations were expected to be higher at inland populations because they are further apart from each other, relative to the Peninsula populations. Plant leaf material was collected and AFLP was used to assess the genetic variation. In general, low genetic variation was present within all populations (mean Nei's gene diversity 0.11±0.01) and no significant differences between Peninsula and inland populations were found. Minor differences in molecular variances were found between Peninsula and inland populations (PhiPt=0.11), being double between Peninsula populations (PhiPt=0.08) than between inland populations (PhiPt=0.04). This supports a possible anthropogenic origin of inland populations. Although the genetic variation of populations is very similar, they should not be managed as a single gene pool. Inland populations are more similar to each other compared to the Peninsula ones and therefore might be managed as one genetic entity. In contrast, Peninsula populations show a higher degree of differentiation and should be managed to maintain genetic integrity by minimizing further cross planting. [Copyright &y& Elsevier]

Abstract: Riparian ecosystems in South Africa's fynbos biome are heavily invaded by alien woody plants. Although large-scale clearing of these species is underway, the assumption that native vegetation will self-repair after clearing has not been thoroughly tested. Understanding the processes that mediate the recruitment of native species following clearing of invasive species is crucial for optimising restoration techniques. This study aimed to determine native species recovery patterns following implementation of different management interventions. We tested the influence of two clearing treatments (“fell & remove” and “fell & stack burn”) on the outcomes of passive restoration (natural recovery of native riparian species) and active restoration (seed sowing and planting of cuttings) along the Berg River in the Western Cape. Under greenhouse conditions we investigated seed viability and germination pre-treatments of selected native species. There was no recruitment of native species in sites that were not seeded (passive restoration sites), possibly because of the dominance of alien herbaceous species and graminoids or the lack of native species in the soil-stored seed bank. Germination of our targeted native species in the field was low in both “fell & remove” and “fell & stack burn” treatments. However, “fell & stack burn” gave better germination for the species Searsia angustifolia, Leonotis leonurus and Melianthus major. Seedling survival in the field was significantly reduced in summer, with drought stress being the main cause for seedling mortality. Germination rates in the greenhouse were high, an indication that harvested seeds were viable. Most seeds germinated without germination pre-treatments. We conclude that failure of native seeds to germinate under field conditions, secondary invasion of alien herbs and graminoids, the lack of native species in the soil-stored seed bank, and dry summer conditions hamper seedling establishment and recovery on sites cleared of dense stands of alien trees. For active restoration to achieve its goals, effective recruitment and propagation strategies need to be established. [Copyright &y& Elsevier]

Abstract: The seed characteristics selected for by scatter-hoarding rodents can have an impact on seed morphology, seedling establishment and ultimately on plant community structure. Using Leucadendron sessile (Proteaceae), it was recently discovered that rodents are seed dispersers in the fynbos biome of South Africa. However, little is known about the characteristics of rodent-dispersed seeds and the selective influence rodents have on seed morphology in this biome. We investigated the caching behaviour of rodents and asked whether variation in seed traits (size, hull thickness) influenced whether seeds were more likely to be consumed or cached. Rodents tended to disperse and bury, rather than consume, medium sized L. sessile seeds with medium hull thickness. In contrast, small or thin hulled seeds were preferentially eaten in situ and were seldom buried. Large seeds or seeds with thick hulls were often left untouched at depots. Our results suggest that rodents may impose stabilizing selective pressures on seed size and hull thickness, traits that may also have consequences for seedling mortality, dormancy, competitive interactions and the survival of fires. [Copyright &y& Elsevier]

Abstract: Fynbos Proteaceae that are killed by fire and bear their seeds in serotinous cones (proteoids), are entirely dependent on seedling recruitment for persistence. Hence, the regeneration phase represents a vulnerable stage of the plant life cycle. In laboratory-based experiments we investigated the effect of desiccation on the survival of newly emerged seedlings of 23 proteoid species (Leucadendron and Protea) occurring in a wide variety of fynbos habitats. We tested the hypothesis that species of drier habitats would be more tolerant of desiccation than those from more moist areas. Results showed that with no desiccation treatment, or with desiccation prior to radicle emergence, all species germinated to high levels. However, with desiccation treatments imposed after radicle emergence, there were significant declines in seedling emergence after subsequent re-wetting. Furthermore, other than three species that grow in waterlogged habitats, germination responses could not be reliably modeled as a function of soil moisture variables. An important finding was that the species had highly individualistic responses to desiccation. In conclusion, early seedling emergence represents a species-specific stage that is highly sensitive to a decrease in soil moisture. Since species are killed by fire (non-sprouting), vulnerability to increasing aridity associated with anthropomorphic climate change would increase the odds of local and global extinction. [Copyright &y& Elsevier]

Abstract: The new species, Nanobubon hypogaeum Magee, is known from only a few localities in threatened sand fynbos vegetation along the Western Cape coast from Mossel Bay to Knysna. It differs from all others in the genus by the slender, slightly woody subterranean stem, which is pulled deeper into the soil so that the rosette of leaves remains close to the surface. In other respects it is superficially similar to N. strictum but differs in the annual leaves with the petiole twice as long as the blade, cream-coloured petals, and prominently acuminate sepals. An updated key to the genus is presented. [Copyright &y& Elsevier]

Abstract: The addition of carbon (C) to the soil as sucrose has been suggested as a countermeasure to reduce plant available nitrogen (N) and increase the competitive advantage of slower growing native perennial species over faster growing annual species. To make this approach a successful restoration tool, C addition must induce the resident soil bacteria and fungi to immobilize plant available soil nutrients. In this study, both the efficacy of sucrose applications as a restoration aid and their dependence on soil microbial activity were examined in field and greenhouse trials. Carbon as sucrose (200gm−2) was added to normal and sterilized soils containing various combinations of native perennial and annual species. Their effects on soil N levels, as well as on the photosynthetic efficiency, growth and N uptake of the introduced native species, were measured. Diminished foliar chlorophyll contents, effective quantum yields (ΔF/Fm′) of Photosystem II (PSII) and dry mass accumulation in response to sucrose applications were observed in both the annual and perennial introduced species, but were not reflected in corresponding reductions in soil N levels. These sucrose-induced inhibitory effects, as well as diminished plant N uptake, were more pronounced in normal than sterilized soils. This implied a bacterial component immobilizing soil N essential for plant photosynthesis and growth. However, this premise was partly contradicted by the unaltered total bacterial numbers following sucrose application in the normal soils, although coliform numbers did increase with sucrose application in these soils. These findings point to a likely abiotic mechanism of sucrose-induced inhibition of photosynthesis and growth in introduced native plants, which renders sucrose application ineffectual as a restoration aid in transformed lowland fynbos ecosystems. [Copyright &y& Elsevier]

Abstract: Two new species of Ficinia (Cypereae, Cyperaceae) are described from South Africa. Ficinia has its centre of diversity in the Greater Cape Floristic Region (GCFR), with c. 90% of the species growing in the Fynbos biome. Recent collections from the arid edge of the Fynbos biome and in the Succulent Karoo biome have revealed two species new to science. Both are perennial plants that lack leaf blades and have sticky leaf sheaths. [Copyright &y& Elsevier]

Abstract: The early post-fire plant succession in fynbos vegetation in the Mediterranean-type climate area of South Africa was studied. Relatively little has been published on this early stage of plant succession in fynbos. Annual sampling over the first three post-fire years confirmed a steady, but relatively slow increase in plant canopy cover of shrubs and graminoids (mainly Restionaceae), whereas cover of geophytes and other herbs peaked in the first year and declined significantly, thereafter. Cover of annual plants increased each year, which may relate to the persistence of a relatively open vegetation cover by the third year. The responses of reseeder and resprouter species of the Restionaceae to the post-fire environment appeared to be habitat dependent. Cover of the reseeders increased rapidly in seep areas, but their recovery was distinctly delayed in dryland areas outside the seeps. Re-establishment of the many reseeder Erica species appeared to be delayed until the second post-fire year. Seed banks of these species were possibly negatively impacted by the fire, and required dispersal of seed from unburnt areas for recruitment. In contrast to some current generalisations, species richness appeared to increase after the fire; less certainly from the first to the second year, but more certainly from the second to the third year. Therefore, this study does not support a short-term monotonic decline in species richness after fire in fynbos. [Copyright &y& Elsevier]

Abstract: Diascia caitliniae K.E.Steiner is a new species of Diascia sect. Diascia from the northern end of the Piketberg, Western Cape. It resembles D. elongata in floral and seed morphology but is distinguished by having pedicels that are flattened and ribbon-like throughout their length and stamens and stigmas that are longer, more exerted, and strongly curved forwards. D. caitliniae is known from two localized populations on adjacent farms and is restricted to lower slopes in areas transitional between fynbos and renosterveld vegetation. It is strongly dependent on fire for germination and flowering. The largest population is threatened by the development of an open-pit tungsten mine and both populations are threatened by potential agricultural expansion up the slopes of the Piketberg. [Copyright &y& Elsevier]

Abstract: Six-hundred-and-fifty plant species from 280 genera and 85 families have been recorded as indigenous to the Bontebok National Park (BNP), which lies 5km south of Swellendam, in the Western Cape. Twenty-nine of these plant species are globally threatened with extinction and another 23 are species of conservation concern. Three species (Aspalathus burchelliana, Diosma fallax, Erica filamentosa) are endemic to the park. The Asteraceae, Iridaceae and Fabaceae ranked high as speciose families, in line with the Cape Floristic Region (CFR) as a whole, while the Asphodelaceae, Crassulaceae, Poaceae and Cyperaceae were overrepresented, and the Rutaceae, Proteaceae and Ericaceae underrepresented at BNP. The largest genera were Aspalathus (19 species), Crassula (17), Pelargonium (16), Erica (15), Oxalis (12), Moraea (11), Helichrysum (10) and Hermannia (10). Geophytes were the dominant growth form (23% of species recorded), followed by dwarf shrubs (20%), herbs (16%), graminoids (15%), shrubs (13%), succulents (8%), trees (3%) and climbers (2%). Forty alien plant species were recorded (likely an underestimate of true numbers) with the Poaceae most speciose and arguably the biggest invasive threat at the park. With 20 plant species/km2, the flora of BNP is richer than expected based on its location within the south-eastern CFR. Similarity with floras of other lowland and montane protected areas in the region is low (<33% and <20% respectively), demonstrating that a large component of BNP''s flora is not conserved elsewhere. Within a landscape context, BNP forms part of a cluster of connected core sites for Renosterveld conservation. This work confirms the high importance of BNP for flora conservation nationally and even globally. [Copyright &y& Elsevier]

Abstract: The Hantam-Tanqua-Roggeveld subregion is situated in an area where the Fynbos, Succulent Karoo and Nama Karoo biomes meet. Life form spectra were compiled at a species richness and vegetation cover level in order to determine the affinities of the vegetation of the subregion with respect to its Succulent Karoo, Fynbos and Nama Karoo Biome status. A percentage succulence was also calculated for both species richness and cover. Comparisons of life form spectra and succulence were made across the eight vegetation associations found in the area and across three broad vegetation groups, i.e., Mountain Renosterveld, Winter Rainfall Karoo and Tanqua Karoo. Mountain Renosterveld vegetation was characterised by high chamaephyte, cryptophyte and therophyte species contributions. Compared to the other broad vegetation groups, the Mountain Renosterveld group showed phanerophyte contributions at the vegetation cover level to be highest, but the degree of succulence was low. Winter Rainfall Karoo vegetation was co-dominated by high levels of chamaephyte, cryptophyte and therophyte species with chamaephytes dominating the vegetation cover. Succulent contributions to species richness and cover values were higher than for Mountain Renosterveld vegetation. Tanqua Karoo vegetation was dominated by chamaephyte species or co-dominated by chamaephyte and cryptophyte species with therophyte species contributions lowest of all vegetation groups. Contributions by succulent species to richness and vegetation cover were high in the Tanqua Karoo. Life form spectra of the Mountain Renosterveld associations compared poorly to other sites in the Fynbos Biome. However, the low level of succulence in the Mountain Renosterveld associations also precludes its inclusion into the Succulent Karoo Biome. The large contribution of succulent species at a species and vegetation cover level in Winter Rainfall Karoo and Tanqua Karoo associations confirms that these two groups belong to the Succulent Karoo Biome. Affinities to the Nama Karoo Biome were indicated by the low level of succulence at a vegetation cover level in one of the Winter Rainfall Karoo associations (Roggeveld Karoo). [Copyright &y& Elsevier]

Abstract: This paper evaluates the history of fire management in the Bontebok National Park (3435ha) over a period of almost four decades. A GIS database was compiled of all fires between 1972 and 2009 and the fire regime was analysed in terms of the frequency, season, size and cause of fires. Since the early 1970s, short interval burning was implemented to promote grazing for bontebok, but from 2004 the fire interval was lengthened to favour plant species diversity, an increasingly urgent conservation priority for the park. In total, 43 fires were recorded, ranging in size from 9 to 1007ha, collectively spanning 14013ha. The majority of fires were large (100–500ha), with fires of >100ha accounting for 96% of the area burnt. The overall mean fire return period (FRP) for the park was 7.2years, which is short judged by fynbos standards. FRPs under the old and new management regimes were 6.7 and 10.9years respectively. Under the old regime, FRPs in renosterveld and fynbos were 5.8 and 8.0years respectively. Large parts of the park repeatedly experienced fires at immature vegetation ages resulting in the elimination of slow-maturing seed-regenerating plant species such as Protea repens. Post-fire age distribution was highly skewed towards young vegetation, with 75% of fire-prone vegetation burning at post-fire ages of ≤7years, and <10% of fire-prone vegetation surviving beyond 10years of age. Prescribed and accidental fires respectively accounted for 70% and 30% of the total area burnt. Prescribed burning was mostly done in March–April, and only 8% of the total area burnt, burnt outside of the ecologically acceptable fire season. This study identified areas which have been subject to ecologically appropriate and inappropriate fire return intervals, providing a basis for informed future management and research. [Copyright &y& Elsevier]

Two new species of Asteraceae (tribe Anthemideae, subtribe Pentziinae) from the Cape Floristic Region of South Africa are described. Marasmodes schlechteri Magee & J.C.Manning, a local endemic from the lowlands between Piketberg and the Olifants River Mountains, is distinguished by its spreading leaves with axillary fascicles and relatively large, solitary capitula with obconical involucre borne on very short lateral shoots. Pentzia trifida Schltr. ex. Magee & J.C.Manning is a well-collected limestone fynbos endemic that is readily distinguished by the regularly trifid leaves, broadly cyathiform involucres with lanceolate to oblanceolate bracts, and the well developed pappus extending the entire length of the relatively short corolla tube. [Copyright &y& Elsevier]

Abstract: This paper reviews the results of recent research on riparian vegetation recovery following the clearance of invasive alien plants. In Fynbos, Grassland and Savanna Biomes, riparian ecosystems were found to have relatively-high ecological resilience to invasion by alien plants, except in some situations of closed alien stands (75–100% aerial cover). Where alien invasion is the primary disturbance at a site, and invasion intensity is low (<75% cover, with some indigenous species present), the recovery of riparian vegetation structure and functioning is a realistic goal through alien clearance alone. Careful clearance of the aliens to avoid damage to indigenous species, while ensuring a high kill rate for resprouting alien species, is sufficient action to ensure ecosystem recovery. However, it is important that alien follow-up control is maintained at a sufficient frequency and that adaptive management is exercised to deal with unplanned events, such as fire or a high rainfall year, that may stimulate renewed alien recruitment. In closed alien stands, clearance may be sufficient to restore ecosystem structure and functioning in some situations, but not in others. To be realistic, restoration goals must take into account the planned future use of the riparian zone and the current ecological condition of the surrounding catchment area. Where ecological integrity of the catchment is low (highly transformed, fragmented), restoration of natural riparian vegetation structure or composition is untenable in most cases. A more realistic goal will be to restore basic ecosystem functions through providing a vegetation cover, comprising non-invasive (preferably indigenous) species, that is resilient to flood events and re-invasion by alien plants. The functions restored should include the buffering of the aquatic ecosystem through erosion control, and a return to more natural hydrological flows. In less-transformed catchments, restoring riparian ecosystem structure and composition is a realistic goal where closed alien stands are cleared by the “Fell & Remove” treatment. Seed banks provide indigenous herb and shrub species, but where recruitment is poor, especially after fire, active restoration is beneficial in facilitating vegetation recovery and suppressing alien recruitment. However, the costs and benefits of active restoration need to be further investigated. Simple decision trees with accompanying information boxes and species lists are presented to assist managers. Because of the complexity of the decision process, it is recommended that specialists assist project managers in drawing up site-specific restoration plans that dovetail with alien-clearing plans. This synthesis of research findings, on riparian restoration in alien-invaded riparian zones, provides guidelines for improved management, drawing mainly on papers in this Special Issue. [Copyright &y& Elsevier]

Abstract: Invasion by alien woody species is a major threat to biodiversity and ecosystem function in the Fynbos and Grassland Biomes of South Africa, and riparian areas are particularly affected. Large stands of the Australian Acacia longifolia have been cleared in catchments in the grassy fynbos of the Eastern Cape. After clearing mature stands of A. longifolia, the dead material is usually stacked, left to dry and eventually burned. There is concern that this results in very high fire intensities to the detriment of native seed banks, and it has been suggested that smaller slash stacks or burning when soils are damp could reduce this impact. We examined the effects of soil moisture (moist vs. dry), depth of burial (2 vs. 4 cm below soil surface) and fuel load (small vs. large slash stacks of the kind typically constructed during clearing operations) on soil temperatures and seed viability of A. longifolia and four common native plant species, viz. Hermannia hyssopifolia, Psoralea pinnata, Senecio chrysocoma and Virgilia divaricata. In the field, an experimental burn of two slash piles was performed to determine the soil temperature during fire. Soil temperatures were found to be higher in dry soils, at shallower depth and under higher fuel loads, with the effect of moisture being the most pronounced. Temperatures in dry soils under large stacks exceeded 330 °C at 2 cm depth. A laboratory experiment showed that A. longifolia and P. pinnata had higher germination in moist soils and at lower soil temperatures while V. divaricata showed the opposite response. S. chrysocoma had low germination in all treatments and H. hyssopifolia did not show a consistent response to the treatments. Heat treatment increased germination in all species, and seeds of all species could withstand maximum temperatures of up to 160 °C and sustained temperatures exceeding 100 °C for more than 20 min. The results show that seed banks of these species can survive fires under slash stacks but stacking slash in smaller piles, or burning when soils are moist, reduces the risk of losing seeds in the upper soil layers to extreme soil temperatures. [Copyright &y& Elsevier]

Abstract: Indigenous soil seed banks play a very important role in facilitating the natural recovery of indigenous fynbos vegetation after clearing invasive alien vegetation. In densely invaded areas, there is a reduction in fynbos cover and seed production, and these ecosystems rely heavily on the remaining soil seed bank as a reservoir of plant propagules. This study used the seedling emergence approach to assess recovery potential based on the soil seed banks of riparian and hillslope grassy fynbos communities that had been densely invaded for three decades, with Acacia longifolia as the dominant alien species. Forty-eight species (of which five were aliens), representing 30 genera and 18 families, emerged from the soil seed bank, with Asteraceae and Cyperaceae being best represented. The mean density of indigenous seedlings for the study area was 1582 seedlings/m2. Senecio rigidus exhibited the highest density, with 274 seedlings/m2, followed by Chironia baccifera (151 seedlings/m2) and Rumohra adiantiformis (136 seedlings/m2). Forbs were the most numerous growth form. Two other alien species exhibited comparable seedling densities, i.e. Solanum nigrum (181 seedlings/m2) and Conyza canadensis (98 seedlings/m2). A. longifolia seed densities of up to 4528 seeds/m2 were found by sieving the soil. Results revealed that alien-invaded grassy fynbos had a diverse and viable soil seed bank with relatively high seed densities. Pioneer species were well represented, as well as graminoids in the riparian zone. Species representing some guilds were missing; e.g. serotinous species from the genera Leucadendron and Protea, and few geophytes were present in the hillslope soil seed bank, although ericoid shrubs were well represented. Riparian species such as Cliffortia graminea and common Cyperaceae and Restionaceae species were also not represented in the seed bank. It would appear from this data that the soil seed bank would be adequate to enable a functional cover of indigenous vegetation to re-establish after clearing. In order to improve vegetation structure and composition, the addition of some missing guilds would facilitate restoration, provided that post-clearing follow-up treatments do not prevent or hinder the establishment of these indigenous species. [Copyright &y& Elsevier]