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Wild leafy vegetables are commonly included in the diet of people in rural homesteads of northern KwaZulu-Natal. This study aimed to investigate the nutrient content of one common and nine scarcely known wild leafy vegetables consumed in this area. Ten wild leafy vegetables were analyzed for their proximate composition, amino acids and mineral contents to evaluate their importance in human nutrition. Wild leafy vegetables differed significantly in terms of their nutrient content. Newly recorded and scarcely known wild leafy vegetables Albertisia delagoensis, Ipomoea plebeia, Ipomoea wightii, Limeum sulcatum, Pyrenacantha kaurabassana, Pyrenacantha scandens, Riocreuxia torulosa and Sesamum alatum had all nutrient content higher than well-known Amaranthus hybridus, with very few exceptions. The highest moisture, ash and protein contents as well as total amino acids were recorded in R. torulosa and/or S. alatum. This study recorded for the first time the nutrient content and relationship among nine rare wild leafy vegetables consumed by rural communities in northern KwaZulu-Natal.

Vachellia farnesiana was in cultivation in South Africa as an ornamental tree as early as 1858. The first non-cultivated specimen was collected in 1888 and the first naturalised population in 1952. We surveyed 4.5 km along a seasonal watercourse near Albert Falls Dam in KwaZulu-Natal, South Africa, where a V. farnesiana population was identified in 2016. We found a total of 1203 trees of V. farnesiana, of which 82% of the trees produced fruit. Field observations suggest that this species has the potential to become invasive in South Africa.

A new species Aspalathus abbottii C.H. Stirt. & Muasya, is described. The species is known only from Oribi Flats, KwaZulu-Natal, where it grows in grassland vegetation. The new species is characterised by its rigid spreading habit, densely and shortly villous branches, glabrous bracts and bracteoles, and 1(2) bright yellow flowers borne on short lateral shoots. It is most similar to other grassland species, A. frankenioides DC. and A. gerrardii H. Bol., all from the summer rainfall area of South Africa but differs in its rigid spreading habit, few bright yellow flowers per flowering branchlet, glabrous bracts and bracteoles, villous yellowish-green seasonal shoots, and its pale brown to tan over-seasonal branches with a blackish lattice of peeled bark.

Cytotoxic and mutagenic effects of thirteen commercial herbal mixtures sold in KwaZulu-Natal, South Africa were evaluated using the neutral red uptake (NRU) assay and the Ames test. The herbal mixtures tested included Umzimba omubi , Umuthi wekukhwehlela ne zilonda , Mvusa ukunzi , Umpatisa inkosi , Imbiza ephuzwato , Vusa umzimba , Ingwe ® muthi mixture , Ibhubezi ™, Supreme one hundred ™, Sejeso herbal mixture Ingwe ®, Lion izifozonke Ingwe ®, Stameta ™ BODicare ® and Ingwe ® special muti . The relative cytotoxicity of the herbal mixtures was established by determining their NI 50 values (50% inhibition of neutral red uptake). The test revealed that the most toxic herbal mixture was Umpatisa inkosi with an NI 50 value of 0.016 mg/mL and the least toxic mixture was Stameta™ BODicare® with an NI 50 value of 28.00 mg/mL. The herbal mixtures showed no mutagenic effects against Salmonella typhimurium tester strains TA98, TA100, TA102, TA1535 and TA1537 when the assay was done without S9 metabolic activation. However, four herbal mixtures, Umpatisa inkosi , Imbiza ephuzwato , Vusa umzimba and Stameta ™ BODicare ® showed mutagenic effects against TA98 but not the rest of the tester strains after using S9 metabolic activation. Umpatisa inkosi also exhibited weak mutagenic activity against TA1535 after metabolic activation. The remaining mixtures did not show mutagenic effects against all the tester strains after S9 metabolic activation. The cytotoxic and mutagenic results reported here offer a step toward determining the safety of commercial herbal mixtures in South Africa. Herbal mixtures showing higher cytotoxic and mutagenic effects need to be further investigated for their possible effects on humans.

In sub-Saharan Africa, maize (Zea mays L.) is one of the most nutritional crops and proper storage of seeds continues to be a challenge for subsistence farmers. Storage fungi, which reduce seed quality, become active in seeds when moisture levels are 14% or higher and this is influenced by the way seeds are stored. The aim of the present study was to test germination and vigour of maize seeds that were subjected to traditional storage during 2005 and to test germination of the maize seeds after storage for one year under conditions of fluctuating temperature. A preliminary survey was conducted and maize samples (white and yellow) were collected from small-scale subsistence farmers in northern KwaZulu-Natal (South Africa) and Mozambique. Seeds that were left in the field to dry and seeds that were commercially treated with Celest® XL served as controls. Germination was measured according to the International Seed Testing Association (ISTA) rules. The maize that was left in the field (NHS) to dry gave 100% germination in 2005. The treated control had a germination of 94.0%. Seeds that were imbibed for 40 h had the highest percentage weight increase following rapid imbibition but four of the six samples maintained germination above 70% following slow imbibition. The conductivity of the solute was read following imbibition. Field stored maize had the lowest solute leakage (1181 μS) and this correlated with the high percentage seeds with living tissue as indicated by the tetrazolium staining following rapid (94.4%) and slow (95.8%) imbibition. The number of fungi isolated from the samples reflected the initial condition of the samples with the fungicide treated control having the lowest percentage infection (11%), NHS had 33% and yellow maize that was stored on the cob and had with insect damage (SIH) had the highest, namely 71%. After the first set of experiments, samples were stored at 26–28 °C to simulate the fluctuating original storage conditions. A year later the samples were subjected to the standard germination test. The decline in seed viability during the storage period was exhibited by results of the standard germination test. Maize that was left in the field had a 74.7% decrease in germination while the sample stored in potato bag (PHEL) and the treated control maintained germination above 80%. Two of the six samples failed to germinate. This study also showed that fungicide seed treatment is a viable option to maintain viability of the seeds, especially when the maize is to be stored until the next season.

Bark is an important source of medicine in South African traditional healthcare but is poorly documented. From thorough surveys of the popular ethnobotanical literature, and other less widely available sources, 174 species (spanning 108 genera and 50 families) used for their bark in KwaZulu-Natal, were inventoried. Vernacular names, morphological and phytochemical properties, usage and conservation data were captured in a database that aimed to synthesise published information of such species. Data specificity was found to be the major limiting factor in the study and resulted in uneven distribution of information in the database. Overlapping vernacular names recorded in the literature indicated that it may be unreliable in local plant identifications. Most (43%) bark medicines were documented for the treatment of internal ailments. Sixteen percent of species were classed in threatened conservation categories, but conservation and management data were limited or absent from a further 62%. There is a need for research and specialist publications to address the gaps in existing knowledge of medicinal bark species and their management to conserve the South African flora.

Vegetation data from southern KwaZulu-Natal were analysed. TWINSPAN classification separated the entire data set (547 releves) into five subsets, One subset, representing the vegetation of the incised river valleys and dry upland savanna of southern KwaZulu-Natal, was further classified by Braun-Blanquet procedures. Five plant communities and nine sub-communities were identified and described. The results can be integrated with existing phytosociological classifications of the Grassland Biome.

A survey of concentrations of selected metals in some common seaweeds from the KwaZulu-Natal coast was conducted. Samples of 40 seaweeds were collected from Palm Beach, Isipingo Beach and Mission Rocks and analysed for metals by X-ray fluorescence. High metal concentrations were found in a number of the seaweeds examined, Stypocaulon funiculare (Phaeophyta) and Osmundaria serrata (Rhodophyta) showed high levels of a wide range of metals and are recommended for further study as indicator species for metals in the marine environment of the KwaZulu-Natal coast.

Specimens of a mixed population of Sargassum spp. were collected from Reunion Rocks, KwaZulu-Natal, South Africa over a period of one year. Three general shapes of receptacle were recorded for Sargassum elegans, S. incisifolium and an undescribed species of Sargassum: i) terete, ii) three-cornered and iii) twisted receptacles respectively. The number of conceptacles on the receptacles was enumerated and related to the dry weight of the receptacles. It was found that conceptacle number per receptacle correlated well to the weight of the receptacle and that, each receptacle type had a different number of conceptacles per unit weight Relationships were found to vary from one season to the next, however, it was found that the three-cornered receptacle type developed a greater number of conceptacles per unit weight than the terete receptacle type. Reproductive:somatic biomass ratios indicated that the three-cornered receptacle type had a lower reproductive expenditure than the terete receptacle type in terms of biomass. Ecological and possible taxonomic implications are discussed.

Isipingo Beach, a sub-tropical rocky shore, is one of eight localities studied in detail by Stephenson and his co-workers during his investigation of the zonation and biogeography of the South African coast. Information collected at these eight localities was used to produce a zonation scheme very similar to the Universal Zonation Scheme’ which is now widely used. Data collected at Isipingo Beach were also used to formulate a more detailed zonation scheme suggested to be typical of the sub-tropical east coast of South Africa Both schemes were based on subjective qualitative observation; in this paper the results of an objective quantitative approach are discussed with respect to the validity of the two zonation schemes, Ordination and classification analyses were applied to community data collected along line transects at Isipingo Beach. The communities indicated by the analyses corresponded well with those suggested by the ‘Universal Zonation Scheme’ and most, but not all. of the communities suggested by the scheme for the sub-tropical east coast were distinguishable. It was concluded that communities which agree with the zones identified by the subjective zonation schemes can be objectively identified.

Encephalartos senticosus is described from the Lebombo Range of northern KwaZulu-Natal and Swaziland. Vegetatively it is similar to E. lebomboensis Verdoorn with which it was previously confused, but differs in its male cones being stalked instead of sessile with the exposed faces of the microsporophylls drawn out into drooping beaks instead of raised pyramidally, and the megasporophylls with exposed faces pyramidally raised instead of more or less flat.

Encephalartos msinganus is described from the Tugela Ferry area in northern KwaZulu-Natal. It resembles E. natalensis R.A. Dyer & Verdoorn in its similar male cones and especially its verrucose female cones, but differs in its much narrower pinnae (16–20 versus 25–45 mm). It resembles E. senticosus Vorster vegetatively and in its similar male cones, but differs in the verrucose instead of smooth exposed faces of the megasporophylls.

KwaZulu-Natal mistbelt ( Podocarpus ) forests serve as sources of firewood, structural timber, traditional food and medicinal products. Of the 3 694 km 2 of these forests in KwaZulu-Natal, only 0.45% is conserved. The extent of patches of Podocarpus forest in 1944 and 1996 within the Midmar catchment, KwaZulu-Natal, South Africa, were mapped from aerial photographs, and compared using a geographical information system. Overall, the area of Podocarpus forest was found to have increased from 784 ha to 804 ha between 1944 and 1996, as did mean patch area (km 2 ), although not significantly. Interestingly, between 1944 and 1996, the number of forest patches decreased by 50%, with many smaller patches present in 1944 having disappeared by 1996. The implications of fragmentation of patches are discussed. Linking of forest patches with corridors of grassland, and further studies on the species composition of these forest patches, is suggested.

In KwaZulu-Natal, most muthis (medicinal plants) associated with male sexual disorders go under the name uBangalala. Our research shows for the first time that the major plant sources for these preparations are three plants from the genus Eriosema ( E. kraussianum , E. salignum and E. cordatum ) and three plants from the genus Salacia ( S. rehmannii , S. leptoclada and S. kraussii ). Since it is the roots that contain the desired active components, and since these roots are purchased without “above-ground appendages” (i.e. leaves and stems), it posed a real challenge to bring together the root and appropriate leaf. However, this was overcome by excursions to the places of origin of the relevant plants. An interesting outcome of this task was the finding that S. rehmannii , not normally associated with KwaZulu-Natal, is quite widespread in the Maputaland Sandveld of this province in the form of S. rehmannii (KB) and S. rehmannii (SB). Indeed, these two plants are a major source of the much sought-after muthi, uBangalala. The active chemical components in the Eriosema plants are two closely-related pyranoisoflavones. The Salacia species mentioned above are rich in triterpene quinone methides, far-removed from the pyranoisoflavones present in the Eriosema series. According to the current literature, the major quinone methide, pristimerin, is used for a variety of ailments, but the evidence that it is associated with male sexual disorders is very tenuous. This, of course, raises the question whether the quinone methides, and particularly pristimerin, have hitherto untested aphrodisiac-like properties, or whether unknown minor components in the plant are responsible for perceived (but untested) sex-related activity.

The effect of simulated harvesting on the biomass and agar content and quality of Gelidium abbottiorum was investigated at Reunion Rocks, KwaZulu-Natal for the period July 1995 to July 1996. There are no previous published records of biomass assessment for seaweeds on the KwaZulu-Natal coast, many of which are of potential economic value. Seaweed samples were collected from Reunion Rocks every three months. This included harvesting the seaweed using two methods, i.e. 'plucking' and shearing'. Biomass was assessed and dry mass values of 255–384 g.m −2 were recorded for the period July 1995 to July 1996. No seasonal differences in biomass were Found for the period July 1995 to July 1996. Standing stocks in commercial beds elsewhere in the world vary from 0.5-1.5 Kg.m 2 fresh mass. The fresh mass of Gelidium abbortiorum was between 0.9–1.4 Kg.m −2 . Therefore, it was concluded that biomass was comparable to that in commercial beds in other areas of the world. Both harvesting methods had the effect of decreasing the biomass over the study period (i.e. from July 1995 to July 1996). It is recommended that 'plucking' be used as a harvesting method if harvesting is to occur at this site. It is suggested that harvesting take place once a year either in spring (September-December) or summer (January-March), Agar was extracted and the quality tested, i.e. gel strength, gelling temperature and melting temperature. Mean agar yields of between 17.5–36.6% were obtained. Gel strength of agar was measured to be between 64.9–291.2.g.cm −2 Gelling temperatures of between 26–34.7 °C were recorded. Melting temperatures of the agar were between 66–77 1 °C. There was no seasonal difference in any of the agar characteristics. It was concluded that agar from this source could be used commercially if blended with superior material from other sources.

A new species, D. flagellaris, is described and illustrated. This species appears to be closely allied to D. calcarata and shares semiepigeal bulbs and evergreen, terete leaves distinguished by their much larger size. No intermediates occur between D. flagellaris and sympatric individuals of D. calcarata. The new species is endemic to the Krantzkloof Gorge system of KwaZulu-Natal.

A survey of 13 vegetation communities which span the major topographic and successional differences in the KwaZulu-Natal Drakensberg was undertaken. A basic description of species present and their abundance was recorded. Furthermore, an analysis was performed to demonstrate the effectiveness of classification and ordination to delimit the representativeness of samples within particular vegetation communities and the relationship between chosen dominant communilies based on homogeneity with regard to species composition and abundance. The analysis was performed using two-way indicator species analysis (TWINSPAN) and detrended correspondence analysis (DCA) to describe the distinctiveness or, in the case of the grassland communities, the close association between the various communities. Results are a record of the dominant vegetation communities within a region displaying a steep altitudinal, and hence environmental, gradient, the homogeneity of samples taken within a community and the distinctiveness and/or similarity between these communities.

Two new species of Lamiaceae are described from South Africa. Thorncroftia lotterii T.J. Edwards and D. McMurtry is described from the mountains that divide Mpumalanga and Swaziland. The species appears to be endemic to the Ugutugulu River Gorge and is closely allied to T. succulenta (R.A. Dyer and E.A. Bruce) L.E. Codd and T. media L.E. Codd. Tetradenia tuberosa T.J. Edwards is described from the midlands of KwaZulu-Natal. It appears to be closely allied to T. barberae (N.E.Br.) L.E. Codd, sharing the occurrence of hermaphrodite flowers.

Holothrix majubensis C. Archer & R.H, Archer, a new species from southern Africa, is described, illustrated and compared with the other related members of the genus. It is a very distinctive species, with a unique combination of glabrous leaves with hairy margins, woolly scapes and non-resupinate, carnose, white flowers with a constantly 3-lobed lip.