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Abstract: Native grasslands are a fundamental part of Canada’s natural heritage, but these formerly extensive ecosystems have undergone declines due to grassland conversion and fragmentation. One threat to remaining native grasslands is invasion by non-native plants, which can outcompete native flora and negatively impact grassland integrity. This study identified patterns of non-native abundance, richness, and individual species occurrences among native grasslands in the Dry Mixedgrass (DMG), Mixedgrass (MG), Northern Fescue (NF), Central Parkland (CP), and Peace River Parkland (PRP) Natural Subregions of Alberta, Canada. Species composition, environmental, and anthropogenic data were collected for 86 plots across the Subregions. Generalized additive models (GAMs) and commonality coefficient analysis were used to identify the strongest predictors for relative cover and richness of non-native plants. In general, abundance and richness of non-native plants were positively linked to moisture and nutrient availability. Aridity and soil fertility were the best predictors across all plots, with mesic loamy grasslands being the most invaded. Patterns of invasion differed between Natural Subregions. In the DMG, relative non-native richness was associated with higher soil carbon content. In the CP, non-native plant abundance and richness was highest in fine-textured fertile soil, as well as on gentle slopes. In the PRP, relative non-native cover was highest on gentle slopes with low pH levels. Kentucky bluegrass (Poa pratensis L.) was the most frequent and abundant non-native plant in this study. Crested wheatgrass (Agropyron cristatum (L.) Gaertner) and smooth brome (Bromus inermis Leysser) were the next most abundant, occurring in clumped distributions in the DMG and CP, respectively. With relatively low cover, dandelion (Taraxacum officinale F.H. Wiggers) and goat’s beard (Tragopogon dubius Scopoli) were the next most frequent. Results suggest that environmental conditions best explain the patterns of non-native plants in Alberta grasslands. However, anthropogenic influences such as agricultural history and proximity, as well as individual species adaptations, may also play a role in the observed patterns. Future avenues for native grassland research include teasing out soil fertility effects and assessing the roles of topography or soil texture on invasion. The patterns of non-native plants identified in this study can also be considered by land managers who are tasked with prioritizing conservation efforts.

Cool season perennial grasses are the foundation of equine nutrition in the transition zone. The objective of this study was to evaluate forage quality using ADF, NDF, IVTDMD, CP, WSC, and ESC and changes in vegetative swards seasonally, diurnally, across species (Kentucky bluegrass, tall fescue, orchardgrass, and perennial ryegrass) and cultivar. This study was conducted in 2015 and 2017 and plots were maintained vegetatively with two to four week mowing. Morning and afternoon sample collection occurred monthly during the growing season. Samples were flash frozen; freeze dried, ground, and scanned using Near Infrared Reflectance Spectroscopy (NIRS) to predict forage quality. There was a significant year effect; therefore year was analyzed separately. Generally, ADF and NDF were highest for Kentucky bluegrass (30 and 52%), lowest for perennial ryegrass (25 and 46%), and tall fescue and orchardgrass were inconsistent. Crude protein was variable across species and season, ranging 10 to 25%. ADF and NDF concentrations were higher in the morning; IVTDMD, WSC, and ESC were higher in the afternoon; and CP was similar diurnally. In conclusion, forage quality in vegetative cool season grass pastures was sufficient to meet the nutritional needs of most equines, but varied seasonally, diurnally, across species, and cultivar.

The story goes that all thoroughbreds, unless bred fraudulently, descend from three foundation sires taken to Great Britain from the Levant, the Maghreb, and Arabia in the late-seventeenth and early-eighteenth centuries. That’s just a story, though, and a breed is more a term of art than a scientific fact. Historian William Cronon implored environmental historians to tell “stories about stories about nature.” The stories people told about thoroughbreds over the breed’s three-century history illuminate unspoken assumptions of their society, assumptions about how inheritance works, about how to organize labor, and about how humans see themselves in their environments. What, for instance, is inherited alongside genes? The language of inheritance is lacking. It conflates the biological, the inevitable, with the social. Inheritance is a social process as well as a biological one. Humans tell stories to make sense of the things carried on from the past; and what we mean when we say something is inherited, includes both the social and the biological. The stories about thoroughbreds are powerful precisely because they make the social, the messy, contingent, and constructed past, seem natural. Thoroughbred breeders narrated their animals in various ways using pedigrees, landscapes, animal bodies, standards, and DNA analysis to tell their stories. I argue that a comprehensive understanding of inheritance must accommodate the discourses that informed breeding decisions. These discourses, as much as genes, had real, material effects on both animals and people. As a category, the thoroughbred has remained more or less constant for three hundred years allowing historians to identify how the discourse around thoroughbreds changed over time, place, and political economic regime. My dissertation begins in the desert outside Aleppo at the turn of the eighteenth century in what was then the Ottoman Empire. British traders working for the Levant Company brought Arabian horses back to Great Britain where they were put to native mares to produce exceptional running horses that became totems of the restored monarchy. When Virginia cavaliers sent their sons to Cambridge for university, the young men grew found of horse racing and shipped their favorite stallions back to the colonies. In Kentucky, thoroughbred owners found a landscape with calcium-rich soil amenable to raising horses for racing. The American Civil War destroyed the South’s horse country, and industrial capitalists from the North adopted thoroughbred racing as their preferred pastime. The new political economy of horse racing prompted a standardization of the breed that turned the animals into fungible commodities. Standardization expanded the geography of horse racing during the Gilded Age, and California’s robber barons struggled to turn their arid latifundia into western simulacra of Kentucky’s Bluegrass Region. With the rediscovery of Mendelian genetics in 1900, racialist thinkers seized upon the thoroughbred to promote ideas of eugenics and racial progress. By the 1980s, thoroughbred racing had been securitized and investors turned to the emerging science of genomics to guide their investments, using thoroughbred horses to promulgate an updated version of genetic determinism. This dissertation follows the thoroughbred breed from its foundation sires in the eighteenth-century Ottoman Empire to the modern animals competing in a globalized horse racing industry. In eight chapters, I investigate thoroughbreds as they fanned out from Great Britain to breeding farms in countries as far flung as Argentina and Zimbabwe. Each chapter focuses on a place and a theme. Chapter One, set in the Ottoman Empire, examines the technology of the animal pedigree adopted from Bedouin traders. British breeders used the pedigree and put a premium on inherited characteristics. Chapter Two identifies the political meaning of breeding as the thoroughbred developed in Great Britain. The thoroughbred became synonymous with the restored monarchy and an emblem of Britishness despite the horses’ obvious Eastern origins. Chapter Three studies the role of the breed in defining a landscape, in particular Kentucky’s Bluegrass Region. Thoroughbred owners in Kentucky’s Bluegrass used their property, both animal and human, to create a landscape that both supported equine reproduction and celebrated the noble animals. Chapter Four follows the adoption of thoroughbred horses as a new form of capital for the American industrial class. Following the Civil War, American industrialists used horses as banks of stored capital and as cultural capital that established the industrialists on the same footing as European aristocrats. Chapter Five highlights the intellectual work necessary to creating thoroughbreds as banks of stored capital. As the scope and scale of raising thoroughbreds increased, owners needed guarantee that a thoroughbred from California was the same as one from New York. Chapter Six moves the narrative to California and shows how that state’s robber barons used thoroughbreds to imaginatively express their vision of industrial capitalism in the western United States. Chapter Seven argues that the elite culture of thoroughbred racing provided racialist thinkers an animal to adopt as experimental animals that purportedly exhibited biological progress. Thoroughbreds, with hundreds of years of pedigrees and breeding data, provided the necessary raw materials for racial scientists. Chapter Eight shows how resilient this narrative of biological progress has been. During the 1980s, increasing capital investment required assurances of success. Investment bankers looked to academic geneticists to provide value for their investments. New genetic testing led to a retrenchment of biological determinism. The stories people told about thoroughbreds—they were myths, really—still shape the industry today and trickle down and inform popular conceptions of inheritance. My dissertation argues that the stories people tell about their livestock have both material and intellectual consequences. Believing that thoroughbreds were noble, gendered, and British by birth justified all kinds of behaviors from land use decisions to scientific racism. From a biological perspective, reproduction is always conservative. Reproduction preserves genes from one generation to another. By looking at the stories people told about thoroughbreds, I show how historical actors used animal husbandry to reproduce and justify the status quo.

Annual bluegrass (Poa annua L.) and roughstalk bluegrass (Poa trivialis L.) are among the most troublesome grass weeds on golf courses throughout the United States. Herbicides for selective control of these weeds in cool-season fairways are limited and ineffective. Methiozolin is a new isoxazoline herbicide that controls annual bluegrass on putting greens and shows promise for possible weed control in fairways. Kentucky bluegrass (Poa pratensis L.) is among the most common turfgrass species used for golf fairways in the Northern United States and its response to methiozolin has scarcely been tested. A 2.5-yr field study was conducted at four Virginia locations to evaluate methiozolin efficacy for selective annual bluegrass and roughstalk bluegrass control in creeping bentgrass (Agrostis stolonifera L.) or Kentucky bluegrass fairways. Another study evaluated the response of 110 Kentucky bluegrass varieties to three rates of methiozolin. Annual bluegrass has long been presumed to impact putting green trueness, or the ability of the greens canopy to provide a smooth and directionally-consistent ball roll. Although much research has evaluated the impact of greens management on ball roll distance, no peer-reviewed research has evaluated how canopy surface factors, such as weedy annual bluegrass, will influence ball roll direction. Laboratory and field research was conducted to elucidate and overcome experimental errors that may be limiting assessment of ball directional imprecision caused by greens canopy anomalies. Techniques to minimize experimental error were employed in field studies at two Virginia golf courses to determine the influence of annual bluegrass on ball directional imprecision, bounce, and acceleration. Study results suggest that annual bluegrass patches in a creeping bentgrass putting surface can cause subtle increases in ball directional imprecision and bounce but several sources of error must be controlled before these effects can be measured. By using a mechanical putter to avoid directional errors associated with simulated-putt devices, selecting golf balls with balanced centers of gravity, eliminating legacy or "tracking" effects of repeated ball rolls via canopy brushing, and scoring ball direction 30 cm prior to terminal acceleration, we were able to detect an increase in ball directional imprecision of 8 mm m⁻¹ when balls rolled over a single patch of annual bluegrass compared to adjacent rolls on visually-pure creeping bentgrass. In herbicide efficacy studies, methiozolin-only treatments did not significantly injure creeping bentgrass or Kentucky bluegrass, reduce quality, or reduce normalized difference vegetative index regardless of application timings and rates. In general, fall applications of methiozolin reduced roughstalk bluegrass and annual bluegrass cover more than the spring-only treatments. At 1 year after the last treatment, methiozolin at 1500 g ha⁻¹ applied four times in fall at 2-wk intervals for two consecutive years controlled roughstalk bluegrass and annual bluegrass ≥85% and more consistently than other herbicides or treatment regimes. Spanning 110 Kentucky bluegrass varieties, a commercially-acceptable threshold of 30% Kentucky bluegrass injury required between 3.4 to more than 10 times the methiozolin rate needed for annual bluegrass control. Results indicate that annual bluegrass increases directional imprecision and bounce of golf balls rolling across a greens canopy. Methiozolin could be a viable herbicide for managing annual and roughstalk bluegrass in Kentucky bluegrass and creeping bentgrass fairways but weed control efficacy may be dependent on application timing. By measuring small differences in ball directional imprecision as influenced by greens canopy factors, future research efforts will aim to help turf managers choose appropriate greens management techniques.

Abstract: Invasion of non-native species such as Poa pratensis L. has become a serious threat to the conservation of bunch grass communities including foothills fescue grasslands in Alberta, Canada. Conservation efforts are currently limited by a poor understanding of the ecological mechanisms responsible for regulating resistance of native grasslands to encroachment by P. pratensis. While invasion of P. pratensis has been linked to summer grazing, we lack an understanding of how environmental conditions (light, soil moisture content and soil N) may influence invasion. Four studies were conducted to determine the individual and interactive effects of environmental and disturbance mechanisms on P. pratensis invasion and the associated vigor of foothills rough fescue (Festuca campestris Rydb.). An in-situ field study within a late-seral grassland suggested that conditions favoring F. campestris (i.e. high soil moisture content, abundant litter, winter defoliation, undefoliated conditions) suppressed P. pratensis, while those favoring P. pratensis (i.e. summer defoliation, litter removal, ambient water) reduced the vigor of F. campestris. Further exploration of this relationship in a variable density planting study under fallow field conditions suggested that the vigor and density of F. campestris were important factors regulating P. pratensis invasion. In a parallel greenhouse study using seedlings of both species, increased soil moisture content, defoliation, and ambient soil N, increased the ability of P. pratensis to suppress F. campestris, but this was much more significant with younger F. campestris plants. Finally tillage and litter removal were the most effective methods of suppressing P. pratensis and increasing the vigor of F. campestris within heavily disturbed grassland. In the latter experiment, establishment method was also important (cuttings = plugs > seeding) in determining the vigor of F. campestris plants. Observed responses suggest that maintaining the vigor of F. campestris within existing grasslands is the best method of suppressing invasion by P. pratensis. P. pratensis suppression may be accomplished through winter defoliation, allowing litter accumulation and minimizing soil nitrogen. Age appeared to be important in determining the competitive ability of F. campestris plants with immature plants appearing more likely to be detrimentally impacted by P. pratensis than more mature plants.

Biostimulants (BIOS) are non-mineral substances that, when exogenously applied in very small quantities, stimulate the metabolic activity of plants. Past research with biostimulants has not included differing levels of nitrogen fertility or shade as variables. The research presented was designed to explore some interactions between biostimulants and nitrogen fertility on turfgrass grown under several light conditions.