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Seisoensveranderinge in die koolhidraatinhoud van jong appelbome
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: P. J.C. Stassen --- ,Gereelde ontledings van die koolhidraatfraksies in jong appelbome het getoon dat suiker 'n relatief klein gedeelte van die koolhidrate in die boomdele uitmaak, en veral in die wortels voorkom. Stysel akkumuleer in die wortels tot finale blaarval in die winter,... -
Seasonal uptake of phosphorus, potassium, calcium and magnesium by young peach trees
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: P. J.C. Stassen --- Department of Agronomy and Horticulture, Republic of South Africa J.D. Stadler --- , Republic of South AfricaTwo-year-old peach trees, grown in sand culture were destructively sampled over a period of 14 months, to determine the uptake of phosphorus, potassium, calcium and magnesium in the new growth (leaves, fruit and new shoots) and in the permanent structure... -
Effect of paclobutrazol on vegetative growth in citrus nursery trees
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.P. Hadlow --- Department of Horticultural Science, Republic of South Africa P. Allan --- Department of Horticultural Science, Republic of South AfricaTwo foliar sprays of paclobutrazol applied at four different concentrations, viz. 50,100, 200 and 500 mg a.i. l−1 on Citrus volkameriana (Ten. & Parq.) under greenhouse conditions, showed that concentrations of 100 mg l−1and above are suitable for reducing undesirable... -
Seasonal variation in forage quality and mimosine contents of two varieties of Leucaena leucocephala
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: AA Akingbade IV Nsahlai CD MorrisSeasonal variation in forage quality and mimosine contents of two varieties (cultivars Cunningham and Spectra) of Leucaena leucocepha/a were evaluated. Cultivar (cv.) Cunningham was available throughout summer, autumn, winter and spring seasons while cv. Spectra was available during summer, winter... -
The effect of Browse Plus™ on nutrient intake, rumen pH and digestibility of a sole diet of Leucaena leucocephala forage
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: MM Majuva-Masafu MJ LiningtonThe purpose of this study was to determine the neutralising effect of Browse Plus™ on condensed tannins in a sole diet of Leucaena forage and how that affected feed intake, rumen environment and passage of nutrients. Partial digestion methods were... -
The effect of feeding varying levels of Leucaena leucocephala on intake and digestibility of low-quality forages in the Highveld of South Africa
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: MM Majuva-Masafu MJ LiningtonThe purpose of this study was to determine the effect of varying levels of Leucaena supplement on the intake, flow and digestibility of nutrients of two low-quality forages. Partial digestion methods were used. The overall results showed that the supplementation... -
Estimation of browse biomass of Ficus thonningii, an indigenous multipurpose fodder tree in northern Ethiopia
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Mulubrhan Balehegn --- Department of Animal, Rangeland and Wildlife Sciences, Ethiopia EA Eniang --- Department of Forestry and Wildlife, Nigeria Abubeker Hassen --- Department of Animal and Wildlife Sciences, South AfricaFicus thonningii is a multipurpose browse tree in northern Ethiopia. Despite its importance, techniques for quantifying its browsable biomass have not been developed. To develop best-estimation equations, the dendrometric parameters total height (H), crown height (CH), crown diameter (CD), diameter... -
Predicting fir trees stem diameters using Artificial Neural Network models
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: MariaJ. DiamantopoulouThe financial exploitation of forests constitutes an important part of human activity. This effort is being made in order to conserve the sustainable exploitation while avoiding the degradation of the environment. One of the most important operations in forest mensuration... -
Survey of Indigenous Tree Uses and Preferences in the Eastern Cape Province
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: H. van Eck --- Faculty of Forestry, South Africa C. Ham --- Faculty of Forestry, South Africa G. van Wyk --- Faculty of Forestry, South AfricaA survey was undertaken in four areas in the Eastern Cape Province to establish indigenous tree use patterns and preferences. Through informal interviews a list was compiled of the 25 most popular indigenous trees being used for their fruit and... -
An investigation into the establishment of indigenous trees on treated mine residue soils in South Africa
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: NeerajM. Dharamraj --- , WilmaG. Gaum --- Department of Applied Natural Sciences, South Africa Annelize Hildebrand --- Department of Applied Natural Sciences, South AfricaMine residue soils have been the cause of barren landscapes and due to its toxic nature, these soils have proved difficult in establishing any form of vegetation. A selection of indigenous tree species mainly used for the establishment of indigenous... -
Cutting down very simple trees
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Alois PanholzerWe study here, by using a recursive approach, the number of random cuts that are necessary to destroy a random tree of size n for simply generated tree families. Crucial for the applicability of such a recursive approach is a... -
Lasiodiplodia species associated with dying Euphorbia ingens in South Africa
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: JA van der Linde --- Department of Microbiology and Plant Pathology, DST/NRF Centre of Excellence in Tree Health Biotechnology, Forestry and Agricultural Biotechnology Institute, South Africa DL Six --- College of Forestry and Conservation, Department of Ecosystem and Conservation Sciences, USA MJ Wingfield --- Department of Microbiology and Plant Pathology, DST/NRF Centre of Excellence in Tree Health Biotechnology, Forestry and Agricultural Biotechnology Institute, South Africa J Roux --- Department of Microbiology and Plant Pathology, DST/NRF Centre of Excellence in Tree Health Biotechnology, Forestry and Agricultural Biotechnology Institute, South AfricaVarious species of Euphorbia occur in South Africa, including herbaceous, succulent and woody types. The largest of the succulent Euphorbia spp. in South Africa is Euphorbia ingens. These trees have been dying at an alarming rate in the Limpopo province... -
A comparison between excavator-based harvester productivity in coppiced and planted Eucalyptus grandis compartments in KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Muedanyi Ramantswana --- Nelson Mandela Metropolitan University, South Africa Andrew McEwan --- Nelson Mandela Metropolitan University, South Africa Jaap Steenkamp --- Nelson Mandela Metropolitan University, South AfricaDue to the labour challenges in South Africa, mechanised forestry equipment has increasingly been required to operate in complex forest conditions – such as coppiced Eucalyptus compartments – where they have not operated before. For this reason, harvesters are either... -
The impact of season, time of defoliation and dehydration on the concentration of mimosine in Leucaena leucocephala forage
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: MM Masafu MJ LiningtonThis study evaluated the variation of the concentration of mimosine in Leucaena forage with season, the time of defoliation and dehydration. Fresh samples were collected randomly from Leucaena regrowth and sorted into four types of samples (primordial tips, young leaves,... -
A Combinatorial Approach for Analyzing the Number of Descendants in Increasing Trees and Related Parameters
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Markus Kuba Alois PanholzerThis work is devoted to a study of the number of descendants of node j in random increasing trees, previously treated in [5, 8, 10, 15], and also to a study of the number of descendants of node j in... -
Performance of planted indigenous trees, Acacia galpinii and Faidherbia albida, in semi-arid Botswana
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: KP Walker JM Theron B MosekiTwo popular indigenous browse, shade and poles trees, Acacia galpinii and Faidherbia albida, were evaluated for survival and growth on-farm in Malotwana, Botswana, with a mean annual rainfall of 450 mm. The trial was a two species × three spacing... -
Comparison of the tolerance of Pinus patula seedlings and established trees to infection by Fusarium circinatum
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: R Glen Mitchell --- York Timbers, South Africa Michael J Wingfield --- Forestry and Agricultural Biotechnology Institute, South Africa Emma T Steenkamp --- Forestry and Agricultural Biotechnology Institute, South Africa Jolanda Roux --- Forestry and Agricultural Biotechnology Institute, South Africa Steven Verryn --- Creation Breeding Innovations cc, South Africa Teresa A Coutinho --- Forestry and Agricultural Biotechnology Institute, South AfricaSince the first appearance of Fusarium circinatum in South Africa in 1990, foresters have been challenged with poor field survival of Pinus patula seedlings at establishment. One of the best long-term solutions is to improve the genetic tolerance of P... -
Patterns of roost site selection and use by Southern Ground-Hornbills in north-eastern South Africa
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Blair A Zoghby --- Percy FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, South Africa Rob M Little --- Percy FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, South Africa Peter G Ryan --- Percy FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, South Africa Philip AR Hockey --- Percy FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, South AfricaDifferent habitats may be used for the needs of various aspects of an animal’s life. Southern Ground-Hornbill Bucorvus leadbeateri groups announce their presence within year-round territories by calling at dawn from their overnight roost sites. Knowledge on ground-hornbill roosting habits... -
Restoration of degraded ecosystems in the Afromontane highlands of Ethiopia: comparison of plantations and natural regeneration
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Abrham Abiyu --- Amhara Agricultural Research Institute, Ethiopia Demel Teketay --- Department of Crop Science and Production, Botswana Gerhard Glatzel --- Institute of Forest Ecology, University of Natural Resources and Life Sciences, Austria Raf Aerts --- Ecology, Evolution and Biodiversity Conservation Section, Belgium Georg Gratzer --- Institute of Forest Ecology, University of Natural Resources and Life Sciences, AustriaThe scale of deforestation in sub-Saharan Africa underscores the need for forest restoration. Information is scarce for evidence-based restoration options. Sown Senna didymobotrya, planted Ficus thonningii cuttings, sown S. didymobotrya and planted F. thonningii combined, and previously occurring native non-browse... -
The decline of an urban Hooded Vulture Necrosyrtes monachus population in Dakar, Senegal, over 50 years
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Wim C Mullié --- , Senegal François-Xavier Couzi --- Société d’Etudes Ornithologiques de la Réunion, France Moussa Sega Diop --- AfriWet Consultants, Senegal Bram Piot --- Cité Ndiatte Almadies, Senegal Theo Peters --- Royal Netherlands Embassy, Senegal Pierre A Reynaud --- 275 Rue Robert Schuman, France Jean-Marc Thiollay --- 2 Rue de la Rivière, FranceAs in many West African cities, in Dakar Hooded Vultures Necrosyrtes monachus have always been characteristic urban scavengers. The recent decline of Hooded Vultures in other parts of Africa, mainly eastern Africa, has been the reason in 2015 for up-listing... -
Predicting site productivity of the timber tree Pterocarpus angolensis
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Vera De Cauwer --- Faculty of Natural Resources and Spatial Sciences, Namibia Esther Fichtler --- Tropical Plant Production and Agricultural Systems Modelling, Department of Crop Sciences, Germany Hans Beeckman --- Service of Wood Biology, Belgium F Patrick Graz --- Faculty of Natural Resources and Spatial Sciences, Namibia Jan Mertens --- Department of Applied Biosciences, Belgium Sam Van Holsbeeck --- Department of Applied Biosciences, Belgium Bart Muys --- Division of Forest, Nature and Landscape, BelgiumPterocarpus angolensis is an important timber tree of the miombo woodlands of sub-Saharan Africa. The species only grows in natural mixed forests and little is known about is productivity potential. This study aimed at investigating productivity of P. angolensis on... -
Genetic variability of the Lessepsian migrant mussel Brachidontes pharaonis (Bivalvia: Mytilidae) in Tunisia
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Antit --- UR11ES12 Biologie de la Reproduction et du Développement animal, Faculté des Sciences de Tunis, Tunisia N Amor --- KSU Mammals Research Chair, Department of Zoology, Saudi Arabia J Urra --- Oceanographic Center of Málaga–Spanish Institute of Oceanography, Spain AN Alagaili --- KSU Mammals Research Chair, Department of Zoology, Saudi Arabia S Farjallah --- Unité de Recherche de Biologie Intégrative et Ecologie Évolutive et Fonctionnelle des Milieux aquatiques, Faculté des Sciences Tunis, TunisiaThe present study used two mitochondrial markers (16S rRNA and COI) to assess the genetic diversity of a newly founded Lessepsian migrant mussel, Brachidontes pharaonis, in Tunisian waters. The species appears to be restricted to only one population in Rades... -
The effect of pre-harvest wind damage on post-harvest quality of ‘Triumph’ persimmon fruit
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Pesanai Zanamwe --- Department of Botany and Biotechnology, South AfricaThe post-harvest quality of ‘Triumph’ persimmon fruits grown in the Western Cape, South Africa varies with seasons. Poor post-harvest fruit quality is assumed to be associated with seasons that are characterized by violent wind occurrences. This study was carried out... -
Roosting requirements of Helmeted Guineafowl Numida meleagris on Highveld grain and livestock farms with alien tree groves, Gauteng province, South Africa
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Johann H van Niekerk --- Department of Environmental Sciences, College of Agriculture and Environmental Sciences, South AfricaThis study describes the relationship between Helmeted Guineafowl Numida meleagris and invasive alien trees on livestock and maize farms south-east of Johannesburg, Gauteng province, South Africa. The dependence of the birds on alien trees affects strategies for the removal of... -
An Economic Assessment of Woodlots for Smallholder Farms in the Coast Region of Kenya
Item type: Journal Article • Journal: East African Agricultural and Forestry Journal • Authors: Linus Wekesa --- Coast Eco-region Research Programme, Kenya Sylivia Mwalewa --- Coast Eco-region Research Programme, Kenya Kevin Muema --- Coast Eco-region Research Programme, Kenya Joseph Muthini --- Coast Eco-region Research Programme, Kenya Phedister Riziki --- Coast Eco-region Research Programme, Kenya Peter Mukirae --- Coast Eco-region Research Programme, Kenya Carolyne Menya --- Coast Eco-region Research Programme, KenyaLittle is known about economic viability of woodlots being integrated in smallholder production systems in the Coast Region of Kenya. The current study was therefore conducted as a cross-sectional survey covering a sample size of 282 smallholder farmers in the... -
Nitrogen mineralisation and N2O emissions in pure and mixed-species plantations of Eucalyptus urograndis and Acacia mangium
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Felipe Martini Santos --- , Brazil Fabiano de Carvalho Balieiro --- , Brazil Danilo Henrique dos Santos Ataíde --- , Brazil Pedro Vaz da Rocha --- , Brazil Bruno JR Alves --- , Brazil Guilherme M Chaer --- , BrazilWe hypothesised that N inputs to the soil from residues of adult trees of Acacia mangium Willd. increase soil nitrate availability and consequently induce higher nitrous oxide (N2O) fluxes, irrespective of being in pure or mixed stands with Eucalyptus. A... -
Restricted inversion sequences and Schröder paths
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: David Callan --- University of Wisconsin-Madison, USA Toufik Mansour --- University of Haifa, IsraelIn this paper, we find an explicit formula for the number of inversion sequences of length n that avoid each of the pattern sets {021, 010}, {021, 011}, {021, 100, 101}, {021, 000, 101}, and {101, 102, 201}. This is... -
Secondary vegetation provides a reservoir of non-timber forest products and agroforestry service options for forestry plantation systems, Maputaland, South Africa
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: AP Starke --- University of Pretoria, South Africa CJ Geldenhuys --- University of Pretoria, South Africa TG O’Connor --- University of the Witwatersrand, South Africa CS Everson --- University of KwaZulu-Natal, South AfricaTree species providing non-timber forest products (NTFPs) have the potential to enhance the socio-economic value of forestry plantation systems and mitigate biodiversity loss associated with production landscapes in Southern Africa. This can be accomplished by integrating NTFP agroforestry systems with... -
Minimising the eccentricity index in trees with given segment sequence
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Imran Allie --- University of Cape Town, South Africa Michael Wade --- University of Cape Town, South AfricaThe eccentricity index of a graph is the sum of the eccentricities of all vertices in the graph. A segment S of a tree T is a subgraph isomorphic to a non-trivial path where all internal vertices have degree 2... -
A note of 2-rainbow edge domination numbers of graphs
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Yu Yang --- School of Mathematics and Statistics, Huaibei Normal University, China Cai-Xia Wang --- School of Mathematics and Statistics, Northwest Normal University, China Shou-Jun Xu --- School of Mathematics and Statistics, Gansu Key Laboratory of Applied Mathematics and Complex Systems, Lanzhou University, ChinaLet G be a graph with edge set E containing no isolated vertices. A 2-rainbow edge dominating function of G is a function f from E to the family of all subsets of {1, 2} such that for each edge...