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Effect of fire intensity on the grass and bush components of the Eastern Cape thornveld
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: W S W Trollope --- Department of Agronomy, Ciskei N M Tainton --- Department of Grassland Science,Fire intensity is an important component of the fire regime and its effect on the grass sward and bush were investigated in the Eastern Cape thornveld. Research indicated that fire intensity had no effect on the recovery of grass after... -
Water utilization patterns around isolated Acacia karroo trees in the False Thornveld of the eastern Cape
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: G.C. Stuart‐Hill --- Department of Agriculture and Water Supply (East Cape Region), Republic of South Africa N.M. Tainton --- Department of Agriculture and Water Supply (East Cape Region), Republic of South AfricaThe effect of various vegetation treatments on two soil moisture regimes (i.e. the proportion of the experimental period where the soil had sufficient water for: (a) growth, and (b) to keep the plants turgid in the vicinity of experimentally isolated... -
Veld management in the communal areas of Ciskei
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: R.G. Forbes --- Department of Livestock and Pasture Science, Ciskei W.S.W. Trollope --- Department of Livestock and Pasture Science, CiskeiVeld management in Ciskei is based predominantly on a communal land tenure system, and livestock is produced under a ‘Group Ranch’ system. Stocking rates are excessively high and consequently veld degradation is severe, resulting in a lowered carrying capacity and... -
Control measures for the encroacher shrub Seriphium plumosum
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: HA Snyman --- Department of Animal, Wildlife and Grassland Sciences, South AfricaSeriphium plumosum encroachment in South Africa has converted extensive areas of grassland into less productive shrubland–grassland, but its control is not being seriously addressed at present. Therefore, the short-term response of S. plumosum to different applications of nitrogen (N), phosphate... -
The economic implications of bush encroachment on livestock farming in rangelands of Uganda
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: S.K. Mugasi E.N. Sabiiti B.M. TayebwaThe objective of this study was to assess the economic implications of shrub encroachment on pastoral rangeland productivity in Mbarara district, in south western Uganda. Sixty pastoral households were surveyed, thirty of which were grazing on cleared farms (with less... -
Effect of long-term exclusion of fire and herbivory on the soils and vegetation of sour grassland
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: L.W. Titshall T.G. O'Connor C.D. MorrisThe effect of long-term exclusion of fire and herbivory, as mediated by aspect, on soils and the structure, composition, and diversity of vegetation was investigated in Döhne Sourveld (34 years), Piet-Retief Sourveld (45 years) and Southern Tall Grassveld (49 years)... -
The influence of tree density on the grass layer of three semi-arid savanna types of southern Africa
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: CGF Richter HA Snyman GN SmitThe influence of bush density on the grass component of the herbaceous layer was investigated for three savanna veld types (Molopo Thornveld, Mixed Vaalbos Thornveld, and the Eastern Grass and Bushveld) in the Northern Cape and North-West Province of South... -
Dietary overlap between Boer goats and indigenous browsers in a South African savanna
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: L Breebaart R Bhikraj TG O'ConnorThe winter diet of free ranging Boer goats in Valley Bushveld, KwaZulu-Natal, was determined by direct observations and compared with the diet of indigenous browsers (kudu, eland, giraffe, black rhinoceros) in order to determine which browsers are most compatible with... -
The coppicing ability of Acacia erubescens and Combretum apiculatum subsp. apiculatum in response to cutting
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: G N SmitThe investigation was conducted in the Limpopo Province of South Africa. Twenty single stemmed trees of both Acacia erubescens and Combretum apiculatum subsp. apiculatum were randomly selected and five trees of each species were cut at heights of 5cm, 15cm,... -
Do we understand the causes of bush encroachment in African savannas?
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: D WardBush encroachment affects the agricultural productivity and biodiversity of 10–20 million ha of South Africa. Many people believe that we understand the causes of bush encroachment. We do not. Many people believe that either fire or heavy grazing by domestic... -
Effects of land tenure, geology and topography on vegetation and soils of two grassland types in South Africa
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: S Vetter WM Goqwana WJ. Bond WW TrollopeA national degradation audit conducted in South Africa in the late 1990s found communal land tenure to be the strongest predictor of vegetation and soil degradation, while abiotic factors such as geology, slope and aspect were also correlated with degradation... -
Review article: Vegetative growth, reproduction, browse production and response to tree clearing of woody plants in African savanna
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: G.N. Smit --- Department of Grassland Science, Republic of South Africa N.F.G. Rethman --- Department of Plant Production and Soil Science, Republic of South Africa A. Moore --- Department of Agriculture, Republic of South AfricaThis review deals with issues including the determinants of vegetative growth of woody plants (soil water availability, water stress, soil nutrient availability, carbohydrate reserves, plant hormones, atmospheric CO2 concentration, tree age, competition, defoliation and shoot pruning, fire, pathogens, soil and... -
Grass defoliation affecting survival and growth of seedlings of Acacia karroo, an encroaching species in southwestern Zimbabwe
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: C. Chirara --- Department of Biological Sciences, Zimbabwe P.G.H. Frost --- Department of Biological Sciences, Zimbabwe V.E.E. Gwarazimba --- Department of Biological Sciences, ZimbabweTwo experiments were conducted, one in the field and the other in the greenhouse, to investigate the effects of the intensity and frequency of grass defoliation on the survival and growth of Acacia karroo seedlings. In the greenhouse, seedlings growing... -
Research note: A preliminary study of the root distribution of Commiphora pyracanthoides Engl. (BURSERACEAE) in the Sweet Bushveld of the Northern Province, South Africa
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: J.J. Jordaan --- , Republic of South Africa J.S. Swart --- , Republic of South Africa S. Venter --- , Republic of South AfricaThe root distribution of Commiphora pyracanthoides Engl., a potential encroaching woody species in the sweet bushveld areas of the Northern Province, South Africa, was studied at the Mara Agricultural Development Centre. The root system of ten C. pyracanthoides shrubs consisted... -
The proposed colonisation sequence of woody species in the Sourish Mixed Bushveld of the Limpopo province, South Africa
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: JJ Jordaan --- , South AfricaThe long-term establishment sequence of the woody component of the Sourish Mixed Bushveld of the Limpopo province was studied and documented. Vegetation surveys were conducted at a protected site at the Towoomba Agricultural Development Centre during 1977 and 2000. Over... -
The influence of Pechuel-Loeschea leubnitziae (wild sage) on grass sward and soil seed bank composition
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: MJ Tedder --- Grassland Science, School of Life Sciences, South Africa KP Kirkman --- Grassland Science, School of Life Sciences, South Africa CD Morris --- Agricultural Research Council, c/o School of Life Sciences, South Africa WSW Trollope --- Research and Development, South Africa MC Bonyongo --- Okavango Research Institute, BotswanaSoil seed banks provide not only a historical record of vegetation composition but also the potential for post-disturbance revegetation. Pechuel-Loeschea leubnitziae (wild sage) is a multistemmed, aromatic shrub, occurring in Namibia, Botswana, Swaziland, Zimbabwe and the northern regions of South... -
Bush clump succession in grassland in the Kei Road region of the Eastern Cape, South Africa
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: TG O'Connor --- , South Africa SC Chamane --- , South AfricaBush encroachment is a vegetation dynamic of global interest. This study describes the pattern of succession of bush clumps in the Eastern Cape, South Africa, using a space-for-time substitution. Clumps formed following establishment of mainly Acacia karroo in grassland through... -
The influence of tree thinning on the establishment of herbaceous plants in a semi-arid savanna of southern Africa
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: G.N. Smit F.G. RethmanThe investigation was conducted on an area covered by a dense stand of Colophospermum mopane. Seven plots (65 m × 180 m) were subjected to different intensities of tree thinning, ranging from a totaly cleared plot (0%) to plots thinned... -
Vegetation change over 40 years in the Weenen/Muden area, KwaZulu-Natal: evidence from photo-panoramas
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: M.T. Hottman T.G. O'ConnorThe utility of panoramic photographs for studying the extent and pattern of vegetation change, in particular of bush encroachment, was investigated by revisiting thirteen sites in the Weenen and Muden areas of KwaZulu-Natal that had been photographed in 1955. The... -
A demographic perspective on bush encroachment by Acacia karroo in Hluhluwe-Imfolozi Park, South Africa
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: DA Balfour JJ MidgleyAcacia karroo has invaded large areas of the Hluhluwe part of the Hluhluwe-Imfolozi Park, despite the relatively frequent fire regime (mean and median fire frequency of 2.9 and 1.3 years, respectively) of this area. We surveyed A. karroo demography and... -
The effects of soil conditions and grazing strategy on plant species composition in a semi-arid savanna
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: M-L Britz D WardThe tree:grass ratio of savannas is important, especially in the semi-arid savannas of South Africa. An increase in tree cover leads to reduced productivity and profitability of rangelands. We investigated the effects of soil type and grazing strategy on the... -
Disturbance and the frequency of root suckering in an invasive savanna shrub, Dichrostachys cinerea
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: JL Wakeling WJ BondThe ecology of clonal species has rarely been studied in savannas. Dichrostachys cinerea, a common invasive shrub in southern African savannas, forms root suckers. This paper examines the effect of disturbance type and frequency on this form of clonal spread... -
Fire can suppress the development of macrophyllous thickets
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Paul Gordijn --- South African Environmental Observation Network, Grasslands, Wetlands and Forests Node, South Africa David Ward --- School of Life Sciences, South AfricaThe ingression of woody plants into savannas, known as bush or shrub encroachment, has become a global concern. Fire has been acknowledged as a key factor in managing woody vegetation in savannas. This study assessed the role of fire in... -
Vegetation change in northern KwaZulu-Natal since the Anglo-Zulu War of 1879: local or global drivers?
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Jennifer Russell --- School of Life Sciences, South Africa David Ward --- School of Life Sciences, South AfricaThe quality of the landscape is declining in many grassland and savanna areas of Africa as a consequence of woody plant encroachment. We investigated the changes in vegetation at selected sites on the battlefields of the Anglo-Zulu War of 1879... -
A century of woody plant encroachment in the dry Kimberley savanna of South Africa
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: David Ward --- School of Life Sciences, South Africa M Timm Hoffman --- Plant Conservation Unit, Botany Department, South Africa Sarah J Collocott --- School of Life Sciences, South AfricaWoody plant encroachment is frequent in dry savannas. Grazing is often considered to be a major cause of encroachment in dry savannas because grasses are removed by livestock, leaving bare areas for trees to colonise in wetter years. Earlier experiments... -
Habitat preference of the eastern population of the Short-clawed Lark Certhilauda chuana in the Limpopo province, South Africa
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Sean M Marr --- Department of Biodiversity, School of Molecular and Life Sciences, South Africa Joseph I Grosel --- Department of Biodiversity, School of Molecular and Life Sciences, South Africa G Derek Engelbrecht --- Department of Biodiversity, School of Molecular and Life Sciences, South AfricaThe southern African endemic Short-clawed Lark Certhilauda chuana has two geographically isolated populations. Little is known about the smaller eastern population, which is restricted to the Polokwane Plateau, South Africa. To provide input for a conservation strategy for the eastern... -
Locally high, but regionally low: the impact of the 2014–2016 drought on the trees of semi-arid savannas, South Africa
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: AM Swemmer --- , South AfricaDrought is thought to be a factor limiting the abundance of shrubs and trees in savannas, but this has rarely been tested empirically. The severe drought of 2014–2016 provided an opportunity to document the impact of drought on the mortality... -
Interactive effects of prescribed fire and livestock grazing on Seriphium plumosum in South African sour bushveld
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Michele D Clark --- , United States Carissa L Wonkka --- , United States Urs P Kreuter --- , United States William E Rogers --- , United StatesDocumented increases in woody plant abundance worldwide can reduce land value and grazing capacity. Throughout many grasslands and savannas in South Africa, Seriphium plumosum, an encroaching woody plant, has been rapidly displacing desirable native species. Cost-effective management techniques are required,... -
Accounting for land cover changes and degradation in the Katse and Mohale Dam catchments of the Lesotho highlands
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Jane Turpie --- , South Africa Grant Benn --- , South Africa Mark Thompson --- , South Africa Nigel Barker --- , South AfricaRangeland conditions in the Lesotho highland dam catchment areas is important for local livelihoods and regional water supply. We investigated changes in land cover and condition from 1991 (before construction) to 2013, using Landsat imagery. The Normalised Difference Vegetation Index... -
Effect of encroaching woody plant species on soil nutrients and selected soil chemical properties in communally managed semiarid savanna grazing lands in the North West province, South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Pieter W Malan --- , South Africa Makuété A P Tiawoun --- , South Africa Khumoetsile S Molatlhegi --- , South Africa Simeon A Materechera --- , South AfricaWoody plant encroachment is recognised as one of the major threats to biodiversity in ecosystems. In many arid and semiarid areas of South Africa, indigenous encroacher species are proliferating, but the factors that favor their abundance are poorly understood. This... -
Water uptake plasticity of savanna trees in encroached grassland: small trees match the mature trees
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Séraphine Grellier --- , France Jean-Louis Janeau --- , France Patricia Richard --- , France Nicolas Florsch --- , France David Ward --- , United States Thierry Bariac --- , France Simon Lorentz --- , South AfricaProcesses linked to woody plant encroachment in grassland are still not well understood, especially the interactions between trees and soil water availability. Our aim was to study the depth of water uptake by trees in grassland and its controlling factors... -
Woody cover change in relation to fire history and land-use in the savanna-woodlands of north-east Namibia (1996–2019)
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Glynis Humphrey --- , South Africa Conor Eastment --- , South Africa Lindsey Gillson --- , South Africa M Timm Hoffman --- , South AfricaVegetation cover estimates for trees, shrub-grass mosaics, and grassland and bare ground, were quantified in the savanna-woodland of Bwabwata National Park, north-east Namibia. Changes in woody cover were analysed using repeat photographs in combination with aerial photographs and recent satellite... -
The effect of changes in human drivers on the fire regimes of South African grassland and savanna environments over the past 100 years
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: James R Puttick --- , South Africa M Timm Hoffman --- , South Africa Timothy G O’Connor --- , South AfricaFire is a key regulator of tree cover in grassy ecosystems, but century-long changes in fire regimes have not been explicitly quantified in South Africa. This study aimed to determine changes in the fire regimes of South Africa’s grassy biomes... -
Occurrence of Dalbergia obovata in grasslands of urban nature reserves within a metropolitan municipality: Is it an encroaching woody species?
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Terry Stewart --- , South Africa Peter F Scogings --- , South Africa Himansu Baijnath --- , South AfricaThe occurrence of Dalbergia obovata, which is typically associated with forests, in grasslands within conservation areas in a metropolitan municipality was investigated to assess whether it was encroaching and what the possible causes might be. Relevant legislation has not regarded... -
Warming promotes growth of seedlings of a woody encroacher in grassland dominated by C4 species
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Lusanda Ncisana --- , South Africa Ntuthuko R Mkhize --- , South Africa Peter F Scogings --- , South AfricaLittle is known of warming effects on growth and defence of woody seedlings that potentially invade grasslands. We predicted that elevated temperatures would increase growth and spine length of Vachellia sieberiana seedlings growing (1) with or without grass in the... -
The chemistry of the pedoderm – part 2: Dichrostachys cinerea patches and adjacent grassland in the southern Kruger National Park, South Africa
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Anthony J Mills --- , South Africa Tercia Strydom --- , South Africa Jessica L Allen --- , South AfricaThe small tree, Dichrostachys cinerea, occurs in dense patches within grasslands on gabbro-derived soils in the southern Kruger National Park. It is not known whether soil properties in the grasslands affect tree establishment. As a first step in identifying soil... -
Effect of land use/land cover changes on water quality in the Upper Athi River sub-catchment in Kenya
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Margaret Waturu --- The Technical University of Kenya, Kenya Lewis Sitoki --- The Technical University of Kenya, Kenya Joseph Lalah --- The Technical University of Kenya, Kenya Stanley Chasia --- The Technical University of Kenya, Kenya Evance Mbao --- The Technical University of Kenya, KenyaThe unprecedented pollution of Athi River has negatively impacted the downstream communities who depend on the river's waters. Moreover, the Upper Athi River Catchment has recently experienced an increase in human population coupled with rapid industrialisation, which has led to... -
The control of the encroaching shrub Seriphium plumosum (L.) Thunb. (Asteraceae) and the response of the grassy layer in a South African semi-arid rangeland
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: A Marquart --- North-West University, South Africa E Slooten --- North-West University, South Africa FP Jordaan --- , South Africa M Vermeulen --- , South Africa K Kellner --- North-West University, South AfricaLarge-scale bush encroachment within rangelands is of increasing concern for land users. The aggressive encroachment of the woody shrub Seriphium plumosum (L.) Thunb. (Asteraceae), previously known as Stoebe plumosa, has resulted in a reduction in productivity, causing large socio-economic challenges,... -
Quantifying the effect of chemical bush control of
Senegalia mellifera on vegetation production in the Eastern Kalahari Bushveld, South AfricaItem type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: --- , South Africa --- , South Africa --- North-West University, South AfricaBush encroachment is the invasion of whole landscapes by indigenous and alien woody species. An imbalance in the ratio of grasses to bushes is a consequence of bush encroachment due to competition for moisture, nutrients and sunlight. This imbalance results... -
Drought release and post-drought changes in herbaceous composition and diversity in two land uses subjected to selective bush control in a semi-arid Kalahari savanna
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: N van Staden --- North-West University, South Africa A Marquart --- North-West University, South Africa K Kellner --- North-West University, South AfricaLand degradation due to bush encroachment and drought threatens the well-being of land users and forage production in the semi-arid savannas of southern Africa. This study aimed to analyse how herbaceous vegetation in the Kalahari savanna can recover from drought,... -
Grass dynamics along a woody-plant density reduction gradient in a South African savanna
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Piet Monegi --- Animal Production–Agricultural Research Council, South Africa Ntuthuko R. Mkhize --- Animal Production–Agricultural Research Council, South Africa Julius T. Tjelele --- Animal Production–Agricultural Research Council, South Africa David Ward --- Kent State University, United States Zivanai Tsvuura --- University of KwaZulu-Natal, South AfricaWoody plant encroachment threatens ecosystem services and functioning, thereby reducing herbaceous plant population persistence and community stability. We assessed the impact of woody removal intensity (WRI) on the grass ground cover, grass composition, diversity and richness, and rangeland condition in... -
Putting the pieces together: woody plant encroachment across a precipitation gradient in southern Africa
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: David Ward --- Kent State University, USAWoody plant encroachment is one of the most widespread land-cover changes in many countries. We put the data together along a precipitation gradient within southern Africa from 150 mm/annum (Namibia) to 1 500 mm/annum (eastern KwaZulu-Natal, South Africa). We found...