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Horseweed and giant ragweed are competitive, annual weeds that can negatively impact crop yield. Biotypes of glyphosate-resistant (GR) giant ragweed and horseweed were first reported in 2008 and 2010 in Ontario, respectively. GR horseweed has spread throughout the southern portion of the province. The presence of GR biotypes poses new challenges for soybean producers in Canada and the United States. Halauxifen-methyl is a recently registered selective herbicide for broadleaf weeds, for preplant use in corn and soybean. There is limited literature on the efficacy of halauxifen-methyl on GR horseweed and giant ragweed when combined with currently registered products in Canada. The purpose of the experiment was to determine the effectiveness of halauxifen-methyl applied alone, and tank-mixed for GR giant ragweed and GR horseweed control in glyphosate and dicamba-resistant (GDR) soybean in southwestern Ontario. Six field experiments were conducted separately for each weed species over 2018 and 2019. Halauxifen-methyl applied alone controlled GR horseweed 72% at 8 weeks after application (WAA). Control was improved to >91% when halauxifen-methyl applied in combination with metribuzin, saflufenacil, chlorimuron-ethyl + metribuzin and saflufenacil + metribuzin. At 8 WAA, halauxifen-methyl controlled GR giant ragweed 11%; glyphosate/2,4-D choline, glyphosate/dicamba, glyphosate/2,4-D choline + halauxifen-methyl and glyphosate/dicamba + halauxifen-methyl controlled GR giant ragweed 76 to 88%. This study concluded that halauxifen-methyl applied preplant in a tank-mixture can provide effective control of GR giant ragweed and horseweed in GDR soybean.
Can multicellular life be distinguished from single cellular life on an exoplanet? We hypothesize that abundant upright photosynthetic multicellular life (trees) will cast shadows at high sun angles that will distinguish them from single cellular life and test this using Earth as an exoplanet. We first test the concept using unmanned aerial vehicles at a replica moon-landing site near Flagstaff, Arizona and show trees have both a distinctive reflectance signature (red edge) and geometric signature (shadows at high sun angles) that can distinguish them from replica moon craters. Next, we calculate reflectance signatures for Earth at several phase angles with POLDER (Polarization and Directionality of Earth's reflectance) satellite directional reflectance measurements and then reduce Earth to a single pixel. We compare Earth to other planetary bodies (Mars, the Moon, Venus and Uranus) and hypothesize that Earth's directional reflectance will be between strongly backscattering rocky bodies with no weathering (like Mars and the Moon) and cloudy bodies with more isotropic scattering (like Venus and Uranus). Our modelling results put Earth in line with strongly backscattering Mars, while our empirical results put Earth in line with more isotropic scattering Venus. We identify potential weaknesses in both the modelled and empirical results and suggest additional steps to determine whether this technique could distinguish upright multicellular life on exoplanets.
Dialects in the South East of England are very often perceived as one homogenous mass, without much regional variation. Rosewarne introduced the notion of Estuary English and defined it as ‘variety of modified regional speech [ . . . ] a mixture of non-regional and local south-eastern English pronunciation and intonation’ (Rosewarne, 1984). However, studies such as Przedlacka (2001) and Torgersen & Kerswill (2004) have shown that, at least on the phonetic level, distinct varieties exist. Nevertheless, very few studies have investigated language use in the South East and even fewer in the county of Sussex. It is often claimed that there is no distinct Sussex dialect (Coates, 2010: 29). Even in the earliest works describing the dialect of the area (Wright, 1903) there are suggestions that it cannot be distinguished from Hampshire in the west and Kent in the east.
Tolpyralate is a new 4-hydroxyphenyl-pyruvate dioxygenase (HPPD)–inhibiting herbicide for weed control in corn. Previous research has reported efficacy of tolpyralate + atrazine on several annual grass and broadleaf weed species; however, no studies have evaluated weed control of tolpyralate + atrazine depending on time-of-day (TOD) of application. Six field experiments were conducted over a 2-yr period (2018, 2019) near Ridgetown, ON, to determine if there is an effect of TOD of application on tolpyralate + atrazine efficacy on common annual grass and broadleaf weeds. An application was made at 3-h intervals beginning at 06:00 h with the last application at 24:00 h. There was a slight TOD effect on velvetleaf, pigweed species, and common ragweed control with tolpyralate + atrazine; however, the magnitude of change throughout the day was ≤3% at 2, 4, or 8 wk after application (WAA). There was no effect of TOD of tolpyralate + atrazine on the control of lambsquarters, barnyardgrass, and green foxtail. All weed species were controlled ≥88% at 8 WAA. There was no effect of TOD of tolpyralate + atrazine application on corn yield. Results of this study show no evidence of a TOD effect on weed control efficacy with tolpyralate + atrazine.
This study consisting of six field experiments was conducted in 2018 and 2019 to evaluate the tolerance of four corn hybrids (P9998AM, P9840AM, DKC42-60RIB, and DKC43-47RIB) to the tank mix of tolpyralate + atrazine with a commercial glyphosate formulation. At 1 wk after application (WAA), two corn hybrids (P9998AM and P9840AM) exhibited more injury from tolpyralate + atrazine (2× rate) applied alone and in combination with glyphosate than DKC42-60RIB and DKC43-47RIB; however, all corn hybrids responded similarly with respect to visible injury 2, 4, and 8 WAA, stand loss, and yield. Application of tolpyralate + atrazine or glyphosate + tolpyralate + atrazine at the 2× rate caused greater corn injury (up to 27%) than tolpyralate + atrazine or glyphosate + tolpyralate + atrazine at the 1× rate (up to 8%) at 1 WAA. The addition of commercial glyphosate with tolpyralate + atrazine did not enhance injury symptoms. Results of this study show that there is a wide margin of corn safety with tolpyralate + atrazine applied alone and in combination with a commercial formulation of glyphosate.
Passive acoustic monitoring is rapidly gaining recognition as a practical, affordable and robust tool for measuring gun hunting levels within protected areas, and consequently for its potential to evaluate anti-poaching patrols’ effectiveness based on outcome (i.e., change in hunting pressure) rather than effort (e.g., kilometres patrolled) or output (e.g., arrests). However, there has been no report to date of a protected area successfully using an acoustic grid to explore baseline levels of gun hunting activity, adapting its patrols in response to the evidence extracted from the acoustic data and then evaluating the effectiveness of the new patrol strategy. We report here such a case in Cameroon’s Korup National Park, where anti-poaching patrol effort was markedly increased in the 2015–2016 Christmas/New Year holiday season to curb the annual peak in gunshots recorded by a 12-sensor acoustic grid in the same period during the previous 2 years. Despite a three- to five-fold increase in patrol days, distance and area covered, the desired outcome – lower gun hunting activity – was not achieved under the new patrol scheme. The findings emphasize the need for adaptive wildlife law enforcement and how passive acoustic monitoring can help attain this goal, and they warn about the risks of using effort-based metrics of anti-poaching strategies as a surrogate for desired outcomes. We propose ways of increasing protected areas’ capacity to adopt acoustic grids as a law enforcement monitoring tool.
Preplant (PP) herbicide applications are an important tool within an integrated weed management system, specifically in no-till production. An understanding of crop tolerance regarding PP applications is important for effectively integrating a new herbicide into no-till cropping systems. Twelve field trials (six in corn and six in soybean) were conducted over a 2-yr period (2018 and 2019) near Exeter and Ridgetown, ON. The purpose of these studies was to evaluate the tolerance of soybean and corn to halauxifen-methyl applied PP, PRE, or POST at the registered rate (5 g a.i. ha−1) and twice the registered rate (10 g a.i. ha−1), hereafter referred to as the 1× and 2× rate, respectively. All trials were kept weed-free throughout the growing season to remove the confounding effect of weed interference. Halauxifen-methyl applied 14 d preplant (DPP), 7 DPP, 1 DPP, and 5 d after seeding (DAS) at the 1× and 2× rates caused ≤10% visible soybean injury. In contrast, halauxifen-methyl applied POST (cotyledon–unifoliate stage, VE-VC) caused 67% to 87% visible soybean injury, a 50% to 53% reduction in height, 65% to 81% decrease in population, 56% to 67% lower biomass, and 53% to 63% decline in yield. Halauxifen-methyl applied 10 DPP, 5 DPP, 1 DPP, 5 DAS, and POST (spike–one leaf stage, VE-V1) at the 1× and 2× rate caused ≤3% visible corn injury and caused no effect on corn height or biomass. Halauxifen-methyl applied at VE-V1 at the 2× rate reduced corn yield 10%. Based on these studies, the current application restriction of 7 DPP in soybean and 5 DPP in corn is conservative and could be expanded. Expanding the application window of halauxifen-methyl would increase the utility of this herbicide for producers.
Horseweed is a competitive summer or winter annual weed that produces up to 230,000 small seeds per plant that are capable of traveling more than 500 km via wind. Giant ragweed is a tall, highly competitive summer annual weed. Glyphosate-resistant (GR) horseweed and GR giant ragweed pose significant challenges for producers in the United States and Ontario, Canada. It is thought that an integrated weed management (IWM) system involving herbicide rotation is required to control GR biotypes. Halauxifen-methyl is a new selective broadleaf POST herbicide registered for use in cereal crops; there is limited information on its efficacy on horseweed and giant ragweed. The purpose of this research was to determine the efficacy of halauxifen-methyl applied POST, alone and in a tank mix, for the control of GR horseweed and GR giant ragweed in wheat across southwestern Ontario. For each weed species, an efficacy study consisting of six field experiments was conducted over a 2-yr period (2018, 2019). At 8 wk after application (WAA), halauxifen-methyl, fluroxypyr/halauxifen-methyl, fluroxypyr/halauxifen-methyl + MCPA EHE, fluroxypyr + MCPA ester, 2,4-D ester, clopyralid, and pyrasulfotole/bromoxynil + ammonium sulfate controlled GR horseweed >95%. Fluroxypyr and MCPA provided only 86% and 37% control of GR horseweed, respectively. At 8 WAA, fluroxypyr, fluroxypyr/halauxifen-methyl, fluroxypyr/halauxifen-methyl + MCPA EHE, fluroxypyr + MCPA ester, fluroxypyr/halauxifen-methyl + MCPA EHE + pyroxsulam, 2,4-D ester, clopyralid, and thifensulfuron/tribenuron + fluroxypyr + MCPA ester controlled GR giant ragweed 87%, 88%, 90%, 94%, 96%, 96%, 98%, and 93%, respectively. Halauxifen-methyl and pyroxsulam provided only 45% and 28% control of GR giant ragweed, respectively. Halauxifen-methyl applied alone POST in the spring controlled GR horseweed but not GR giant ragweed in winter wheat.
Chapter Two explores how court officials tried to come to terms with Zhu Di’s deep engagement with the steppe and its leaders. Zhu Di’s five steppe campaigns were more than military conflicts. Zhu Di visited the sites – sometimes ruins – of former Yuan palaces and lodges. He offered commentary on the Yuan ruling house, which accentuated his status as successor to the Great Yuan and as a ruler uniquely qualified to pass judgment on fellow sovereigns. Zhu Di’s actions challenged civil officials in many ways. They had to praise a sovereign who openly flouted the founder’s precedents. They celebrated the emperor’s newest subjects, men who drank blood, consumed raw liver, and exulted in physical strength. Court ministers’ writings depicted a style of rulership obviously connected to men from afar in ways that simultaneously satisfied their sovereign’s demands and minimized dangers to the polity and to themselves.
The Conclusion offers observations about what the study’s main findings reveal about Ming rulership and the Ming throne’s place in east Eurasia. It argues that the Ming throne actively sought allies in Eurasia through political patronage, economic support, and a rhetoric that highlights the ties of good faith and loyalty between the emperor and Mongol nobles at home and abroad. The Conclusion also briefly critiques New Qing History exceptionalism, suggesting that the Ming throne’s engagement in Eurasia is one chapter in a far longer story of China’s deep ties to neighboring polities.
Using the unusually rich historical sources generated by the Tumu crisis, Chapter Four offers a reconstruction of Ming rulership in east Eurasia in the mid-fifteenth century. Chapter Four demonstrated that the fifteenth century’s first half saw a multigenerational, multifaceted competition among Mongol, Oirat, and Ming ruling elites to turn the Chinggisid legacy to their advantage. Each developed a genealogy or pedigree of rulership, which it advertised to its neighbors. The best-documented example, that of the Ming dynastic house, trumpeted the superior attributes of the rulership of Zhu Yuanzhang and his descendants. Just as emphatically, the Ming throne denied the qualifications of rival lords such as Toqto’a-Buqa and Esen. The Ming ruling family and its close supporters tried to persuade several audiences, including Jurchen chieftains, the Choson throne, and Oirat and Mongol leaders, of its historical vision of the past and the present.
Chapter Three is a group biography of Mongols in the early Ming throne’s service. Zhu Di and his advisers depicted Esen-Tügel’s decision to join the Ming dynasty in 1423 as a submission, which proved Zhu Di’s superior attributes of rulership. The emperor’s martial prowess, munificence, and ability to recognize men of outstanding ability regardless of their origin won the allegiance and service of a proven Mongol warrior and leader. As was often the case, this dramatic moment – an oath of personal fealty – commanded chroniclers’ attention, but the bigger story had yet to unfold. Imperial patronage continued for much of the remainder of the fifteenth century. It took material form in housing, wages, and personal gifts. It also came in the guise of tax exemptions, prestigious titles and posts, opportunities for advancement, and the throne’s conspicuous protection. Successive emperors displayed their favor through material, financial, political, and honorific means. Such patronage extended to hundreds of Mongolian men, their families, and their descendants for decades and decades. Men from afar embraced this face of rulership. At the same time, it was a pattern of behavior that many civil officials rejected, in part because they felt that such generosity came at their expense.
The introduction discusses the core issues and organization of the book. It argues that despite long-standing stereotypes about Chinese isolation, the Ming court was fully engaged in foreign relations in Eurasia and that relations with Mongol nobles in particular figure prominently in the perception and representation of Ming emperors’ identity and style of rulership.
Zhu Di’s experience as imperial prince shaped his rule’s style and substance. He interacted with Mongolian men as subordinates, advisers, allies, negotiating partners, rivals, and traitors. He was known among them as Lord of Yan. Breaking with his father’s example, Zhu Di repeatedly campaigned in person on the steppe as emperor. There he met with steppe leaders, hosted banquets, conducted grand hunts, and organized vast military reviews. He spoke openly of his motives and objectives on the steppe, not just to audiences at home but also with Korean, Jurchen, Mongol, Moghul, and Timurid leaders. He inserted himself into a Chinggisid world as east Eurasia’s premier ruler and patron.