As pollinator populations decline globally, public interest in creating pollinator gardens to help sustain bee abundance and diversity is rising, and there are many lists of recommended pollinator plantings and suggestions for bee-friendly flowers. However, these suggestions often lack grounding in empirical data. While anecdotal and expert suggestions are not without merit, it is crucial that we have clear, replicable, evidence-based planting recommendations to help boost the abundance and diversity of pollinators that will visit the plants. To fill this gap, we created a pollinator garden containing 25 pollinator plantings, some on previous recommendation lists, some not, and that were either native or non-native and perennial or annual. We surveyed the number and taxonomy of pollinator visitors to these plants through non-destructive methods. These data were analyzed to determine which plants are most effective at attracting abundant and diverse flower-visiting insects. We analyzed preference between native and non-native plants, perennials and annuals, and among different plant species. Our data revealed significant variation in the total abundance and diversity of flower-visiting attracted insects among plant species. Brown-eyed Susans attracted the highest abundance of insect visitors (average number of visitors per day = 53) and were 26-fold more attractive than Begonias, which attracted the lowest abundance of insect visitors (average number of visitors per day = 2). Lavender attracted the highest diversity of insect visitors (Simpson's Reciprocal Diversity Score: 3.5) compared to Pineapple Sage (Simpson's Reciprocal Diversity Score: 1.6), which attracted the lowest diversity of insect visitors. Additionally, we found that native perennials significantly attracted the greatest abundance of visitors compared to either non-native annuals or non-native perennials (p < 0.001). We conclude that ornamental landscape plants can support an abundance and diversity of pollinator visitors, and planting schemes should take into consideration the effects of plant species, plant lifespan, and plant origin. We can use these data to better inform the regional community how to attract and support abundant and diverse pollinator populations within urban and sub-urban ornamental landscape gardens. / Master of Science in Life Sciences / Many people want to build gardens with flowers that are attractive to pollinators, which can be bees, flies, butterflies, moths, and other insects. How, though, do we know what should be planted in that garden? Anyone with access to a computer can find lists of recommended plants for a pollinator garden, and they are provided by a variety of sources. However, the plants included on these lists are often not the same. Some lists may claim a handful of plants are the most attractive to pollinators, while another list will suggest different plants as the most attractive. In addition, these lists often are not based on scientific evidence. Our goal was to use these recommendations to build a pollinator garden so that we can collect data on the plants and determine which plants are best in our garden at attracting insect pollinators. We created a pollinator garden that includes 25 of popular landscape plants, many of which are found on lists of current plant recommendation lists. Then we let the plants grow and bloom, and during the summer, we counted and identified the different species of insects found on each plant. We then ranked plants, from best to worst, at their ability to attract insects and pollinators in numbers and in diversity. Additionally, we found that insects are generally more likely to visit plants that are native to the region. Using this information, we can share our results with the public so that anyone can build their own pollinator garden that will be the most attractive to pollinators.

Increases in agricultural intensification over the past century have resulted in significant alterations to the rural landscape across the Midwest. Pollinators are essential to sustain natural and managed ecosystems. They are vital for food production and their declines have been linked, in part, to a rise in intensive agricultural practices. There is a recognized need among numerous stakeholders to build sustainability into the management of agroecosystems to protect both the biotic and abiotic resources of these systems. The use of cover crops is gaining interest among agricultural producers for benefits such as improving water quality and soil health. Cover cropping systems have the potential to provide floral resources to pollinators and suppress problematic driver weeds. The overall objective of this study was to quantify the effects of cover crops on plant and pollinator biodiversity within agricultural systems. This study aimed to characterize the pollinator diversity indicative of the patchwork mosaic forest-agroecosystem of Crab Orchard National Wildlife Refuge; evaluate the roles cover crop treatments play in supporting pollinator diversity and weed suppression benefits in a conventionally managed system; and provide the basis of recommendations for sustainable weed suppression tactics and for enhancing the quality of pollinator habitat within agricultural systems.

Thesis (Ph. D.)--University of Washington, 1999. / Vita. Includes bibliographical references (leaves 96-112).

Thesis (M. Sc.)--University of Canterbury, 2008. / Typescript (photocopy). Includes bibliographical references (leaves 62-79). Also available via the World Wide Web.

Thesis (M.S.)--Oregon State University, 2007. / Printout. Includes bibliographical references (leaves 44-52). Also available on the World Wide Web.

Pollination is an important ecosystem service necessary for 80% of global plant reproduction. This service can also improve fruit production and is essential for 84% of all crops grown in the EU. However, some pollinators have been declining for the last decades and the important honey bee is no exception. One of the reasons to this decline is believed to be agricultural use of chemicals (i.e. fungicides, herbicides and insecticides). One of the most commonly used herbicides is RoundUp, which include glyphosate as its active substance. In this study, I test if RoundUp affects honey bee behaviour by exposing them during a short-term period to one of three different concentrations (0 mg/l, 5 mg/l and 50 mg/l). The test was conducted in a wind tunnel and aimed to test the hypothesis that glyphosate affects searching abilities and flight time of honey bees. In contrast to my hypothesis, I was unable to detect effects on searching ability. However, method limitations might have been the reason only three bees, out of 147, found the food. My analysis showed neither any effects from RoundUp on fly time (P&gt;0.05) or activity (P=0.066). However, in my data I could see a negative trend in activity and due to earlier data collected around glyphosate, I argue that exposure to glyphosate might have a negative long-term impact on honey bee survival.

Pollination is an essential ecosystem service, increasing reproductive success of many crops, which can be provided by managed pollinators, wild bees (including honeybees) and other insect pollinators. However, the pollination services and the economic value of wild pollinators are often underestimated. Better understanding of the factors that influence honeybee foraging behaviour and pollination efficiency can contribute to the improvement of management practices that aim to enhance crop pollination and ecosystem services. The objectives of this study were to investigate the importance of managed honeybees and wild honeybees to sunflower pollination as well as to evaluate the response of honeybees to different levels of floral rewards and to behavioural interactions with wild flower visitors. The study was conducted in 16 commercial sunflower farms and one experimental farm of South Africa during the 2009 sunflower flowering season. The results showed that insects, particularly honeybees, were efficient pollinators, improving sunflower production in all self-fertile sunflower cultivars used in this study. Furthermore, wild honeybee colonies were found to be as efficient as managed honeybee colonies in sunflower pollination near to natural habitat. Both sunflower yield and the abundance of pollinators decreased with distance from natural habitat, suggesting that sunflower yield is directly correlated with the abundance of pollinators. The amount of nectar present in the florets of sunflower significantly affected pollinator behaviour, influencing honeybee visitation length and foraging rate which prefer to exploit floral rewards from the same source if they find the higher amount per foraging trip, possibly having a negative impact on cross-pollination. Moreover, the concentration of nectar collected from honeybees was significantly lower than the nectar concentration from florets, suggesting that honeybees diluted highly concentrated sunflower nectar with their saliva to their optimum concentration level. Interspecific exploitative competition between honeybees and wild pollinators (wild bees, butterflies and moths) significantly increased the movement of honeybees among sunflower heads, which enhances cross-pollination. Furthermore, behavioural interactions influenced the length of foraging time spent by individual honeybees per sunflower head. Butterflies were the most influential in enhancing honeybee foraging movement, followed by wild bees and then moths. The importance of a given flower visitor species to honeybee movement is likely related to the size of the visitor, as the bigger size of butterflies and movement of their wings increases the chance of disturbing a neighbouring honeybee. Conservation of natural habitat is important to maintain the diversity of flower visitors which indirectly contribute to crop production by enhancing honeybee foraging activity and consequent direct pollination service. Furthermore, the pollination effectiveness of wild pollinators, density of wild honeybees surrounding sunflower fields and effects of human activities on pollination disruption are suggested as topics for future research. / Dissertation (MScAgric)--University of Pretoria, 2010. / Zoology and Entomology / unrestricted

Pedicularis sceptrum-carolinum is threatened in much of its geographic range. As it reproduces vegetatively only to a limited extent, the species relies heavily on pollinators for reproduction. One aspect often overlooked in restoration efforts is the pollination ecology of flowering plants and their pollinators. To get a better understanding of the pollination ecology of P. sceptrum-carolinum in northern Sweden, their flower visitors were identified, and the number of flower visits was counted for flowering individuals at three different sites. The nearby flowering plant community was inventoried around each investigated P. sceptrum-carolinum. It was tested whether the number of flower visits were similar among sites, between large and small populations, and between populations with a majority of fresh flowers and populations with a majority of senescent flowers. To investigate whether the nearby plant community is important for the pollination of the species, the correlation between flower visits of P. sceptrum-carolinum and nearby flower abundance and diversity was analysed. No difference was found between sites, between large and small populations, or between populations where the majority of flowers were fresh and populations with a majority of flowers which had senesced. A moderate positive correlation was found between number of flower visits and nearby flower abundance and diversity respectively, if one site with an exceptionally large abundance of Trifolium pratense was excluded. As abundance and diversity of the nearby flowering plants were themselves highly correlated, their individual effect on flower visits of the studied P. sceptrum-carolinum could not be told apart in this study.

Conservation of natural habitats and planting wildflower plots are two commonly promoted tactics to enhance pollination services and biological control of crop pests, which are ecosystem services that can improve agricultural outputs. There are several programs at various levels of government in the United States that landowners can use to defray the costs of implementing these conservation strategies. Studies of European Agricultural Environmental Schemes have shown these tactics to have positive outcomes for crop production. However, real-world applications of cost-sharing programs have not been evaluated in the United States on pollination services and biological control. Furthermore, these tactics may inadvertently perform ecosystem disservices, like increasing crop pests or creating habitat for disease vectors. In this study, we evaluated the effects of natural habit and wildflower plots on biological control, pollination services, bee communities, and tick populations in Eastern Virginia and Maryland. This research was conducted on 22 farms. 10 of these farms had wildflower plots that were designed by Natural Resource Conservation Service personnel, and implemented by cooperating farmers. Collards, strawberries, tomatoes, and squash were used as model systems. We measured pest density, sentinel egg predation, crop damage, seed pollination, biomass production, marketable crop yield, sampled the bee community, and recorded tick abundance in wildflower plots. Many of the measures of biological control and pollination services had idiosyncratic results in regards to the wildflower plots and natural habit in the landscape. However, the proportion of high quality yield for all four crops increased with increasing natural habitat in the landscape. Bee communities between sites with and without wildflower plots were not different. Bee abundance did increase at wildflower sites when natural habitat comprised a certain proportion of the habitat around the site. Ticks were sampled from wildflower plantings, but not in greater abundance compared to field margins. In this study, the effects of wildflower plots were overshadowed by the landscape effects of natural habitat. Government personnel that oversee these programs may need to consider the surrounding landscape when helping implement on-farm conservation measure like wildflower plots. Such measures, do not perform an ecosystem disservice in regards to ticks. / Doctor of Philosophy / Conservation of natural habitats and planting wildflower plots are two strategies to enhance pollination services and biological control of crop pests. These two ecosystem services are of needed to improve agricultural production without further damaging the environment. There are several programs at various levels of government in the United States that landowners can use to subsidize the costs of implementing these strategies. European studies have shown these government programs to be successful. However, these programs have not been evaluated in the United States on their ability to enhance pollination services and biological control. Furthermore, studies investigating potential ecosystem disservices these strategies. In this study, we evaluated the effects of natural habit and wildflower plots on biological control, pollination services, bee communities, and tick populations in Eastern Virginia and Maryland. This research was conducted on 22 farms. 10 of these farms had wildflower plots that were designed by Natural Resource Conservation Service personnel, and implemented by cooperating farmers. Collards, strawberries, tomatoes, and squash were used as model systems. We measured pest density, egg predation, crop damage, seed pollination, and yield. We also sampled the bee community, and recorded tick abundance in wildflower plots. There were no consistent trends for many measures of biological control and pollination services in response to the wildflower plots and natural habit. However, the proportion of high quality yield for all four crops increased with increasing natural habitat in the landscape. Bee communities between sites with and without wildflower plots were not different. Bee abundance did increase at wildflower sites when natural habitat comprised a certain proportion of the habitat around the site. Ticks were sampled from wildflower plantings, but not in greater abundance compared to field margins. In this study, the effects of wildflower plots were overshadowed by the landscape effects of natural habitat. Government personnel that oversee these programs may need to consider the surrounding landscape when helping implement on-farm conservation measure like wildflower plots. Such measures, do not perform an ecosystem disservice in regards to ticks.

No description available.