Thesis (M.Agr.Stud.) - University of Queensland, 2005. / Includes bibliography.

Experiments were conducted to evaluate the reproductive biology, cytology and phenology of the Australian everlasting daisy Rhodanthe anthemoides and related species. The principal objective was the development of new cultivars with novel bract colours and an assessment of intra-specific variation, mutation breeding and inter-specific hybridisation with R. diffusa, R. manglesii and R. chlorocephala subsp. rosea was carried out.R. anthemoides is a variable eastern state species and plants collected from the New England region of N.S.W have a chromosome number of 2n=22 as does R. diffusa. Other distinct morphological types of R.anthemoides, mostly from the Alpine regions of N.S.W, returned counts of 2n-22 indicating that this species is cytologically divergent and in need of botanical revision with the recognition of at least one new species.R. anthemoides is outbreeding and features a conspicuous involcure, protandry and long stigmatic papillae which aid in pollen presentation and favours insect pollination. The stigma in this species becomes receptive before it is fully exposed and remains receptive for at least 8 days. All of the above species are strongly self-compatible and in R. anthemoides the SI system functions by inhibiting pollen tube penetration of the stigma. (For complete abstract open document)

Thesis (Ph.D.) - University of Queensland, 2003. / Includes bibliography.

Thesis (M.Sc.(Crop Science) North-West University, Mafikeng Campus, 2011

Thesis (M.Phil.)--University of Queensland, 2003. / Includes bibliography.

South Africa is not well endowed with indigenous forests which are now known to be degraded and declining at unknown rates. This constitutes a direct threat to quality of life of the resource-poor rural households who directly depend on them and to ecological integrity. It is also recognised that the declining tree resources, particularly the high value indigenous tree species, are increasingly threatened by a number of growing subsistence demands. This emphasised the need to cultivate and conserve high-value tree species such as Englerophytum natalense, Ptaeroxylon obliquum and Millettia grandis on-farm in Umzimvubu District. Agroforestry is recognised as a viable option for optimising land productivity, reducing pressure on the indigenous forests, ensuring a sustainable supply of desired tree products and services and improving the quality of life of the resource-poor rural households. This Thesis examines whether agroforestry in Umzimvubu District and similar areas of South Africa has the potential for addressing these needs. It recognises that for successful initiation, implementation and adoption, agroforestry should be considered at two levels, namely, household and institutional. Responses based on structured questionnaires were obtained at these levels. Questionnaires were used to determine whether the households and institutions were aware of, and responding to, the need to intensify and diversify on-farm production, ease pressure on indigenous forest, improve income opportunities and problem solving capacities to address agroforestry related issues. An ecological inventory of E. natalense, P. obliquum and M grandis was carried out to provide a sound basis for integrating high-value species into appropriate agroforestry systems and to facilitate the preparation of future management guidelines for these resources in Mt. Thesiger Forest Reserve. The study: i) confirms that most high value indigenous tree species merit integration into subsistence farming systems through agroforestry, ii) appreciates that some rural households have been unknowingly practising agroforestry, iii) recognises that agroforestry is implied in South Mrica's White Paper on Sustainable Forest Development of 1997, but notes that similar emphasis has not been adopted or incorporated in the National Forestry Action Programme of 1997, and iv) notes that challenges to promoting agroforestry research and development in the South Mrican context of the institutions and resource-poor rural households are many, but can be resolved. The study concludes that agroforestry stands to benefit many resource-poor rural households and enhance environmental resilience in South Africa in the next millennium. / Thesis (M.Sc.) - University of Natal, Pietermaritzburg, 1999.

The Bureau of Land Managements (BLM) Emergency Fire Rehabilitation (EFR) policy was developed in 1985 to encourage protection of sites from soil erosion and to minimize potential changes in vegetation communities that may result from the dominance of weedy species. To achieve the goals of EFR policy, managers often used introduced perennial grasses that established quicker and competed better with introduced annuals than did native plants. However, the change of sagebrush-grass communities to communities dominated by introduced forage grasses has led to concerns for wildlife habitat. This concern contributed to a policy change encouraging the use of native species, when available, for rehabilitation projects. This study attempts to assess the effectiveness of BLM EFR projects in meeting the stated goals of the BLM EFR policy in the Great Basin. To do this, two field offices per state were randomly selected from an inclusive list of all Great Basin field offices. In 2001, we randomly selected three EFR projects per field office from those projects that used native species. On each project site, we used a common monitoring technique in association with monitoring techniques implemented by the BLM to assess if national EFR objectives were being met. A semi-structured survey was developed to determine the potential reasons why native and introduced plants were either used or not used, why monitoring was and was not proposed, and whether monitoring was implemented in rehabilitation projects. BLM monitoring techniques did not adequately evaluate EFR goal achievement. The time it took to implement any of the BLM methods did not differ significantly from the time needed to implement the common protocol on the two projects where BLM had implemented monitoring and used native plants (F[subscript 3,12]=1.63, P=0.23). Cost to implement the common monitoring technique was minimal and it directly measured aspects of stated EFR policy goals. Vegetative cover of all natives, seeded and volunteers, contributed half of the overall cover on EFR projects and was significantly higher than sown introduced species. Invasive species were intermediate and did not differ significantly from either the natives or the introduced. The seeded species were a subset of the native or introduced classes. Composition by cover between sown native, sown introduced, and invasive species did not differ significantly. Vegetation cover increased the surface soil stability 39% of the time and subsurface stability 56% beneath the vegetation. Respondents of the survey stated that they generally use more natives and more complex seed mixtures than they did historically. Many also stated that they prefer to use native over introduced species. However, most felt that introduced species are more effective in meeting EFR goals on the degraded sites than native species. All respondents would like to access a summarized report of other rehabilitation projects. The respondents were split between accessing it through the World Wide Web or through a written report. We believe that a common database could be created and maintained on the World Wide Web if a common sampling protocol was implemented. / Graduation date: 2004

Many plants are not commercially produced due to a lack of accessible information on their horticultural requirements and landscape potential. Members of the Legume Family (Leguminosae) are often conspicuous components of the vegetation of arid and semi-arid subtropical regions. Many of these plants are suitable for landscaping use in areas suited to their cultivation. Coursetia glandulosa, Erythrina flabelliformis, Eysenhardtia orthocarpa, Haematoxylon brasiletto, Lysiloma watsonii, Pithecellobium mexicanum, and Sophora arizonica are woody legumes native to the Sonoran Desert region which offer a variety of form, texture, color and function. All of these plants grow readily from scarified seed. E. flabelliformis and E. orthocarpa are easy to propagate from stem cuttings. Some irrigation is necessary for establishment and reasonable growth in the landscape. Maintenance and pests are minimal. Freezing temperatures are the primary limiting factor to several of the plants. S. arizonica is slow growing and is prone to rot in the nursery.

The objective of this project is to develop an activity guide for the California native plant trail located adjacent to the San Bernardino County Museum that allows families to discover native California plants while increasing environmental and cultural sensitivity.

Thesis (MScFor )--Stellenbosch University, 2003. / ENGLISH ABSTRACT: Species-rich Renosterveld vegetation does not return to old agricultural fields even after many years (10-20) of abandonment. In most cases the fields are slowly taken over by non-indigenous species, particularly alien pasture grasses and African lawn grass. While poor survival of indigenous seedlings due to competition, grazing or any other establishment constraints, might explain the failure of natural vegetation to colonise old fields, here I am testing the hypothesis that recolonisation by indigenous plant species is limited by seed dispersal. I have quantified changes in seed density with distance from the natural vegetation into old fields using seed traps and soil seed bank assessment. I have also looked at seed dispersal in the dung of large herbivores. Shrubs (with the exception of Eytropappus rhinocerotis) were poorly represented in the seed rain indicating that they might be seed limited. Dicerothamnus rinocerotis (a dominant shrub in Renosterveld) and certain geophytes (that were recovered in the soil bank) have proven that seed dispersal is not the primary constraint to their return to ploughed fields. Dicerothamnus rinocerotis produces a large number of seeds that are dispersed long distances into the old field and a number of geophytes were well represented in the soil bank. Large herbivores are dispersing a lot of herbaceous forbs in their dung but make very little contribution to the dispersal of indigenous tussock grass and shrubs. Seeds of indigenous Renosterveld tussock grasses (e.g Tribolium hispidum) were restricted to the edge of the natural vegetation. My research has shown that some indigenous seeds, particularly those dispersed in wind and through large mammals, do reach the old ploughed field. I therefore conclude that seed dispersal is not the primary constraint to the natural recovery of populations of some indigenous plant species on old fields, but may limit recovery of certain indigenous geophytes, grasses and shrubs. / AFRIKAANSE OPSOMMING: Spesie-ryke Renosterveld plantegroei hervestig nie op ou landerye nie, selfs ná baie jare (l0-20) van verlating. Oor die algemeen word hierdie grond stadig oorgeneem deur uitheemse spesies, veral uitheemse weidingsgrasse en kweekgras. Terwyl swak oorlewing van inheemse saailinge as gevolg van kompetisie, weiding of enige ander vestigingsbeperkinge, die mislukte vestiging van natuurlike plantegroei op ou benutte grond kan verduidelik, toets ek hier die hipotese dat hervestiging deur inheemse plantspesies deur saadverspreiding beperk word. Ek het veranderinge in saaddigtheid oor afstand vanaf die natuurlike plantegroei na ou landerye gekwantifiseer, deur gebruik te maak van saadopvangsvalle en sand saadbank beraminge. Ek het ook gekyk na saadverspreiding in die mis van groot herbivore. Struike (behalwe Eytropappus rhinocerotis) was swak verteenwoordig in die "saadreën", wat mag toon dat struike saadbeperk is. Eytropappus rhinocerotis ('n dominante struik in Renosterveld) en sekere geofiete (wat in die saadbank gevind is) het bewys dat saadverspreiding nie die hoofbeperking is vir hulle terugkeer na geploegde lande nie. Eytropappus rhinocerotis produseer 'n groot hoeveelheid saad wat oor groot afstande oor die ou landerye versprei word en 'n aantal geofiete was goed verteenwoordig in die saadbank. Groot herbivore versprei 'n groot hoeveelheid kruidagtige forbe in hulle mis, maar maak 'n baie klein bydrae tot die verspreiding van inheemse polgras en struike. Saad van inheemse Renosterveld polgrasse (bv. Tribolium hispidum) was beperk tot die some van die natuurlike plantegroei. My navorsing het getoon dat sommige inheemse saad, veral dié wat deur die wind en deur groot herbivore versprei word, wel die ou geploegde landerye bereik. Ek maak dus die gevolgtrekking dat saadverspreiding nie die hoofbeperking is vir die natuurlike herstel van populasies van sommige inheemse plantspesies op ou landerye nie, maar mag die herstel van sekere inheemse geofiete, grasse en struike beperk.