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The pollinator spectrum, diversity of flower colour, natural pollination and fruit set levels were examined in Scottish L. borealis patches.  Flowers were visited by a diverse spectrum of insect pollinators but, despite high natural pollination levels, fruit set was very low in the majority of patches examined.  The breeding system of L. borealis was confirmed as highly self-incompatible and limited compatible mate availability was identified as the cause of reproductive failure.  Due to the limited pollen dispersal capabilities of flies which dominate the pollinator spectrum, isolation from pollen exchange between compatible mates began at very short distances.  A diversity of compatible mates situated within close proximity (<6 m) was shown to be the key requirement for high natural fruiting success in L. borealis.  Cross-pollination between neighbouring L. borealis patches resulted in high fruiting success suggesting that transplantation of compatible mates into isolated patches could restore their reproductive success. Natural pollination levels were generally high on Colonsay and a very low, but consistent, level of capsule and seed set was recorded in most years.  Capsules produced by Colonsay plants contained very low quantities of seed (<100/capsule) and high numbers of empty testa, and seed set was extremely low (<1%).  Severe reproductive failure was evident and the cause was attributed to self-incompatibility and/or inbreeding depression.  Seed set was also very low for all of the crosses made within Scotland, even between the two distinct genetic groups.  The high levels of seed set achieved following crossing of Scottish and North American plants suggest that restoration of reproductive success in Scotland may require the introduction of some North American genes.

Melampyrum sylvaticum (small cow-wheat) is a hemiparasitic annual of boreal-montane regions of Europe.  The Species Action Plan recommended that in addition to protecting extant populations, by 2010 there should be an additional five populations that have been created with the aim of enhancing greater genetic diversity of the species.  Consequently this project was set up in order to provide the ecological knowledge required to meet such targets. There are various management options available to conservationists looking to prevent Melampyrum sylvaticum’s extinction from the UK but from the results of this project it is clear that some methods have drawbacks that should preclude their use.  Population augmentation with seeds from other populations is not advised due to the risk of genetic ‘swamping’ or outbreeding depression.  Seed amplification would avoid these problems but may introduce different complications by artificially promoting certain genotypes within a population. Population expansion by mimicking ant dispersal is recommended as a way of minimizing density dependent mortality in larger populations but is not suitable in smaller populations. Seed translocation to unoccupied sites is therefore, the best option but the exact details of seed-sourcing and sowing should be guided by the results of the Species Recovery Project in order to avoid predicted limitations. The long-term outlook for M. sylvaticum will depend entirely on whether populations can be created that operate as part of a functioning ecosystem (including pollinating and seed-dispersing insects) with enough demographic and genetic stability to survive predicted climate change.

The Swede, Carl Linnaeus (1707-1778), introduced an artificial " Sexual System " of plant classification in 1735, and a binomial system of nomenclature in 1753. They made plant identification much easier. The Linnaean period in Britain lasted from 1760 until [1810-]1830. It is demonstrated that it was during this period that it was first recognised that an unusually high number of rare plants grow in Upper Teesdale. Most of the rare plants of the then very remote Upper Teesdale were discovered shortly after 1783 by William Oliver (1760-1816), alone. He was a surgeon and part of a medical dynasty. How he became a botanist, with his medical background, is examined in detail. He trained at Edinburgh but did not do botany. However, he knew John Hope, the Professor of Botany. Hope was one of only two people teaching the Linnaean system in Britain at this time. The appearance of Linnaean floras of Britain in English from the 1770's onwards made field botany accessiblet o anyone. Previously complex natural systems of plant classification and the use of Latin had restricted access. How Oliver's discoveries were made known is examined in detail. It involved Rev. John Harriman (1760-183 1) who was influenced by the Linnean Society of London, formed in 1788, and the Linnaean English Botany which began in 1790. H-e wanted to become a Fellow of the Linnean Society. James Edward Smith was President of the Linnean Society and an author, with James Sowerby, ofEnglish Botany. IV alic, ,j Lrf Edward Robson (1763-1813), a Quaker botanist and already an Associate of the Linnean Society, and his compilation: Plantae rariores agro Dunelmensi indigenae of 1798, and John Binks (1766-1817), an artisan botanist. Medicine made botanists of both Harriman and Binks, as well as Oliver. Linnaeus influenced the teaching of materia medica (the plant simples).

In an era of rapidly changing habitat conditions, integrating conservation genetics and management to maximize the adaptive capabilities of rare species is paramount to their survival. We examine the genetic diversity and reproductive strategies of a rare wildflower endemic to the Florida panhandle, the Florida skullcap (Scutellaria floridana), to inform management and recovery decisions. We revisited almost all populations still considered extant and assessed genetic diversity and prevalence of clonal reproduction using SNP data generated by ddRAD sequencing. We found that populations possess low genetic diversity, moderate evidence of inbreeding, and moderate divergence from one another. We identified eight populations as possessing the majority of diversity within S. floridana’s gene pool and four populations of poor genetic diversity in need of further investigation. We established two plots to investigate asexual reproduction and identified only 2-3 genets out of 25 to 30 ramets in each. We suspect that five populations that we were unable to locate are extirpated and recommend further investigation to determine their status. Scutellaria floridana appears to have experienced a continued decline in the number of extant populations since its listing under the Endangered Species Act and will likely require ongoing monitoring and management to ensure its survival.

Species distribution models (SDMs) have become an essential tool in focusing conservation efforts for species with incomplete distribution records. SDMs enable conservation managers to increase field survey efficiency by prioritizing areas to invest time and financial resources. This application is invaluable for historical species which remain suspended between extant and extirpated, having not been documented in many years, but lack sufficient evidence to be determined extirpated. Identifying suitable habitat and previously unknown locations for species of conservation-concern has historically represented an overwhelming and often impractical task, however the development of model-based sampling approaches has made this task more feasible. Here, SDMs are trained using digitized herbarium specimens to identify suitable habitat and therefore, the potential distribution of 16 historical plant species in Tennessee. The ultimate goal of this work is to provide conservation managers with an effective tool for guiding sampling strategies, enabling the rediscovery of Tennessee’s lost plant species.

The loss of native plant species through habitat loss has been happening in NZ since the arrival of humans. This is especially true in Canterbury where less than 1% of the lowland plains are believed to be covered in remnant native vegetation. Rural land uses are changing and farm intensification is creating novel habitats, including farm irrigation earth dams. Dam engineers prefer not to have plants growing on dams. Earth dams are consented for 100 years, they could be used to support threatened native plants. Within the farm conversion of the present study dams have created an average of 1.7 hectares of ‘new land’ on their outside slope alone, which is the area of my research. This new land represents important sites for vegetation restoration in another wise highly modified landscape. My research aims to discover if earth dams could be used as restoration sites for rare, threatened or at risk native plants. The north and south facing outside slopes of four dams were surveyed to find out which plants have established. Four 5 x 5m quadrats per north or south dam wall were used to identify plant species and ground condition on four dams. Twenty three vascular species were identified from 31 vascular taxa found growing in the quadrats. A combination of dam and aspect had an impact on species diversity in the plots. Only six species were recorded as covering more than 5% of the quadrats. There were significant differences between dam wall aspect in both vegetation height, and ground conditions. Temperature changes recorded over 24 hours were different between the north and south walls of dam 1 and were considered to have implications for planting zones. Five native rare species were chosen due to nursery availability, and studied in detail, from a list of 44 native plants that were recorded in the area of the Te Whenua Hou dams at Eyrewell, Canterbury. The five species are Aciphylla subflabellata, Coprosma intertexta, Leptinella serrulata, Muehlenbeckia ephedroides, Raoulia monroi. Quadrats were used to identify species growing with the rare species and the ground conditions. There were 94 plots studied across 22 sites, across Canterbury, from Culverden in the north to Ealing, Ashburton District, in the south. Altitude varied from sea level to 481m across the species. Plot vegetation cover was significantly different between species even though ground conditions were not significantly different. Both species diversity and vegetation height were significantly different. There were six species that were found in at least one plot of each of the rare species. Roots of seven dam species and four rare species were excavated and scanned using the WinRhizo™ programme at Landcare Research/ Maanaki Whenua for quantitative measurements and to evaluate root traits. The root diameter of the rare species was within the range of the dam species, 0.315 mm for Agrostis tenuis to 0.629 mm for Rumex acetosella. The root volumes of the rare species were larger than the dam species. There was significant difference between the specific root length of the rare species and the dam species. The root diameters imply that the four rare species could be grown on the dams as they all fall within the range of diameters of the established plants. The remaining roots traits imply, that for a restoration site, the dams could be used for the rare species. A protocol has been proposed for planting novel habitats with target species, based on the steps of this research. This includes direct comparison of novel site and target species natural sites as well as root measurements for site specific comparisons.

Most revegetation and ecological restoration projects throughout New Zealand are planted with a limited selection of native plant species. Funding restrictions often do not allow additional time for forward planning of longer term plant community diversity outcomes. Little consideration is made for the emergence of beneficial seedlings, or for the planting of later stage species. The aim of this research was to investigate whether expanding the plant species list proposed for a selected planting area would enhance and extend local biodiversity, if understorey plants are included in longer-term planning. One objective was to enhance an existing ecological restoration project by doubling the number of native species with a selection of regionally rare, less common plants, and common plants with limited sale in nurseries. Twenty-one plant species were selected for the study. This research study was carried out in conjunction with the Wairewa Rūnanga. The hau kāinga hapū (the local people belonging to the Wairewa Marae, are Ngāti Irakehu and Ngāti Makō, (sub-tribes of Ngāi Tahu), are based at Little River and Te Roto o Wairewa / Lake Forsyth, Horomaka (Banks Peninsula), in Canterbury. With the support of a Vision Mātauranga award, the project was based near the Wairewa Marae, and at a nearby partially re-vegetated stream terrace. A preliminary study of archival oral and written histories provided a database of regionally rare or less common plants that were once present in this Banks Peninsula landscape. These included plant species of more particular or significant interest to the Wairewa tangata whenua, (the local people belonging to this area), particularly plants used in Rongoā Māori, (traditional Māori healing). A desk study provided an historical background upon which to base a proposed planting list and site location. Sixteen native plant species were already present in wider adjacent areas of the existing project on the stream banks or in the low terrace areas on the eastern side of the Ōkana Stream, but only 14 species were present in the immediate designated study areas. The additional 21 species planted included 17 taller growing plants, (trees, shrubs, one sedge and climbers) and 4 ground cover species. Of the 21 species, 16 new plant species were introduced into the existing project area. All the plants were monitored over a period of 15 months. The experimental area was a strip of revegetated land approximately 3.5ha (500m long and 70 m wide). Six individual plots (10m x 7m) were located along 70m length of terrace. Each plot measured 70m2 and began at the top of the terrace, with a gentle slope of 0.3m to 1.5 m, down to a low point by the old stream bed. The total width of the study area was 7m for plots on one side, and 7 m wide for plots on the other side of the old stream bed, with a total overall width of the study area of no more than 20m. The experimental plots covered 0.14 ha. A seventh plot was situated at the nearby Wairewa Marae, also measuring 70 m2. A total of 697 plants were included in the field study. Initial strategic planning was found to be important to ensure successful establishment of plants: location and species-suitability issues, as well as known geological, geographical, climatic and biological risks were taken into account at the early stages. Planting techniques, and careful individual plant selection and placement were considered to be important issues. Rare, less common and uncommon plants performed equally as well as the common species. The shade or shelter provided by foliage of the existing plants allowed healthier growth of all species, whereas fringe frost-tender species such as Fuchsia excorticata did not perform as well in the open spaces. One rare species, Pittosporum obcordatum, performed consistently well at all locations. The rate of survival in each species category, was observed in terms of successful establishment, (health and growth), failure, or recovery. Height and health recordings showed that given placement in favourable locations or conditions, such as partial shade or shelter, then the rare, uncommon and culturally useful species could grow equally robustly as the common species. Pseudopanax arboreus had the second highest number of deaths, but was among the tallest growing plants. Three species showed signs of set-backs due to frost damage or summer dryness, followed by new growth and recovery. All Melicytus ramiflorus survived and followed this pattern. When placed in sheltered positions, Pseudopanax arboreus and Fuchsia excorticata, had some success in set-back and recovery. The project resulted in an 87.9% survival rate of the taller plants, and an 82.9% survival rate overall, which included ground cover species. Given the limited period of study and evidence of plant recoveries and set-backs after two winter periods, it was thought that the survival rate maybe improved with further summer data observations. The benefits of a well prepared area in which to allow emergent seedlings to flourish was apparent. Only three emerging seedlings were identified in the unmanaged area compared with several hundred in the managed plots. Many emerging seedlings favoured the protection of the ground-cover species, where these had been placed in cluster groups together. Knowledge gained through this field study has increased biodiversity and Rongoā Māori species in the Te Roto o Wairewa/ Lake Forsyth and Little River areas, informed and raised awareness of the range and opportunities of ecological restoration amongst the Wairewa Rūnanga and local community, and has also advanced restoration practice towards considering how to establish rarer and less common species.

Big Bend National Park in Texas serves as a refuge for many rare plant species, many of which can be found nowhere else in the United States. This study is a summary and synthesis of the available research that has been done on four rare plants in Big Bend National Park: Coryphantha ramillosa subspecies ramillosa (bunched cory cactus), Echinocereus chisoensis var. chisoensis (Chisos Mountain hedgehog cactus), Echinomastus mariposensis (Lloyd’s mariposa cactus), and Festuca ligulata (Guadalupe fescue). The objectives of this study were (1) to review and synthesize all existing published and unpublished studies of these species, with a focus on known threats, conservation priorities, and research needs, (2) to create a GIS database of available public and private data relevant to these species, and (3) using this database, to conduct a preliminary analysis identify the primary habitat characteristics of each of these species at both local and landscape scales. At the landscape scale, geological substrate, elevation, and topographic position characterized species' habitats. At a local scale, slope and sometimes soil unit determined species presence. Further research is needed on each species. Each of these species faces multiple threats, and collaborations between government agencies, private conservation organizations, private landowners, and researchers may be essential to the recovery of these species.

Small populations and rare species offer unique opportunities to study fundamental evolutionary questions, but many rare species are threatened by disturbance and climate change. Molecular population genetics enable biologists to examine evolutionary processes while simultaneously assessing levels of genetic diversity, population structure, and gene flow that can help shape management plans for rare species. However, developing molecular markers can be an expensive, time-consuming process, especially if little is known about the genomes of the species of interest. A new technique, Genotyping by Sequencing (GBS), requires little to no prior information to develop SNP markers. Here I employ this technology to develop hundreds of markers in two rare, serpentine soil-endemic Monardella (Lamiaceae) plant species and a common congener. Using the SNP markers, I investigate population structure, genetic diversity, and hybridization between species. I also use a soil dataset to determine whether species and hybrid zones occur on divergent soils. I find low levels of genetic diversity and little population structure in the two rare species, as expected by rapid genetic drift in small populations. I find evidence of hybridization and introgression among species at sites where multiple species co-occur. Further, Bayesian assignment finds mixed ancestry in one of the rare species. The soil data show that the soils inhabited by the two species are divergent, but not significantly different. Some hybrids occur on soils that seem to be intermediate between the two parental species, but others do not. I synthesize these data with ecological surveys to provide species management recommendations to the USDA Forest Service.

Solidago verna (spring-flowering goldenrod) is a rare endemic primarily of frequently burned longleaf pine flatwoods in the Carolinas. It is listed as threatened in North Carolina and as a federal species of concern. Continued threats to the species are fire suppression and habitat destruction, including planned highway construction through the largest known population. Plants in this threatened population were transplanted into study plots on seven Coastal Plain soils varying in wetness. Full vegetation and reduced vegetation treatments were applied to test the effects of plant interactions. Soil was the most important factor affecting transplant survival. Survival was low in areas where ponding or flooding occured. Plant interaction effects on survival differed significantly among soils. Both increasing soil wetness and the presence of neighboring vegetation negatively affected transplant growth; however, most of the decrease in transplant mass was attributed to other environmental factors, possibly shading from the tree canopy or transplanting stress. We recommend establishing mitigation transplant sites on the Lenoir soil series and burning those sites every 1-3 years.

This study seeks to answer the following questions: (1) What is the current status of the Collinsonia verticillatapopulations in Ohio? (2) What site and vegetation characteristics are typical of the Ohio habitat of Collinsonia verticillata? Previously known populations were ground-checked to determine current population status. Plots were established within selected populations in order to record vegetation and environmental data. The Ohio populations of Collinsonia verticillataare stable, and four new sites were discovered over the course of the study. The habitat sites are on steep north to northeast-facing lower slopes on silt-loam soils with low pH. Associated tree species are white oak, sugar maple, and red maple. Viburnum dentatummay be an associated indicator species. Possible threats to the populations include invasive species, logging, and soil disturbance. Frequent monitoring and removal of invasive plants are needed. Location of additional populations in the future is likely.

Giyen the current world-wide interest in the conservation of threatened species this writer believes that, in New Zealand, Local Authority Parks and Recreation Departments (hereafter referred to as P.R.D.) have a conservation role to play. In particular this is so of those departments which have a botanic garden, a native plant reserve or a native plant domain under their jurisdiction. In fact, P.R.D.s are well placed to undertake the cultivation and propagation of threatened plants. For instance, they have generally speaking, propagation facilities, growing on facilities and skilled horticultural staff. In addition they often have a wide range of habitats within the bounds of their city in which to cultivate a diverse range of plant species. As yet, however, little systematic knowledge has been gathered on the work of New Zealand P.R.D. s in the conservation of threatened species, so that the material discussed in this dissertation is timely and also represents an original documentation of the present situation. At the time of writing however, there does not appear to be any well researched study on the conservation role of organisations like the P.R.D.s operated by the larger local authorities in this country. It is this topic then which is explored in the present dissertation, and is developed in terms of three principal objectives. These are - i) to define the role of P.R.D.s in rare plant conservation, ii) to identify factors which limit the contribution of P.R.D.s to a programme of rare plant conservation, and iii) to identify which P.R.D.s are best equipped to make a positive contribution to rare plant conservation.