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Characterization Of Ground Nozzles For Pesticide Applications, Ryan Henry 2016 University of Nebraska-Lincoln

Characterization Of Ground Nozzles For Pesticide Applications, Ryan Henry

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Pesticide applications are a common component of crop production systems in the United States (US). For row crop systems (e.g. corn, soybean, or wheat), pesticides are applied by ground, aerial, or chemigation methods. The exact method of pesticide delivery is not universally regulated/ prescribed in the US, and the equipment and application technique are largely defined by the individual applicator. A wide variety of choices and decisions must be made by applicators to result in a successful pesticide application. Examples of these choices include proper active ingredient(s), carrier volume and equipment (e.g. nozzle type, spacing, and operating pressure) selection while …


Spatial Variation In Germination Of Two Annual Brome Species In The Northern Great Plains, Erin K. Espeland, Jane M. Mangold, Natalie M. West 2016 United States Department of Agriculture-Agricultural Research Service, Sidney, Montana

Spatial Variation In Germination Of Two Annual Brome Species In The Northern Great Plains, Erin K. Espeland, Jane M. Mangold, Natalie M. West

The Prairie Naturalist

Downy brome or cheat grass (Bromus tectorum L.) and field brome (B. arvensis L.; Synonym = Bromus japonicus Thunb. ex Murr.; Japanese brome) are two annual exotic species that have increased the intensity and frequency of fire cycles in the Intermountain West of the United States, with millions of dollars in associated costs (DiTomaso 2000). These invasive brome species have a different impact in the Northern Great Plains of North America where they commonly co-occur in disturbed sites (White and Currie 1983, Haferkamp et al. 1993). In these mixed-grass prairie rangelands, annual bromes compete against other forage species …


Review Of Waterfowl Of North America, Europe, And Asia: An Identification Guide By Sébastien Reeber, William L. Hohman 2016 United States Department of Agriculture, Natural Resources Conservation Service, Fort Worth, Texas

Review Of Waterfowl Of North America, Europe, And Asia: An Identification Guide By Sébastien Reeber, William L. Hohman

The Prairie Naturalist

Ducks, geese and swans (Family Anatidae) are the most popular and best studied group of birds in the world. The group has been the subject of classical books by Kortright (1942), Delacour (1954-1964), Bellrose (1976), Palmer (1976), Johnsgard (1978), and, most recently, Kear (2005) and Baldassarre (2014). The latest contribution to this rich legacy is an impressively illustrated identification guide for waterfowl found in North America, Europe and Asia by author and artist, Sébastien Reeber. This is an English-language version of Canards, Cygnes et Oies d’Europe, d’Asie et d’Amérique du Nord, published by Delachaux and Niestlé in late 2015. …


Review Of Birds Of Montana By Jeffrey S. Marks, Paul Hendricks, And Daniel Casey, Scott G. Somershoe 2016 United States Fish and Wildlife Service, Lakewood, Colorado

Review Of Birds Of Montana By Jeffrey S. Marks, Paul Hendricks, And Daniel Casey, Scott G. Somershoe

The Prairie Naturalist

The Birds of Montana is an impressive-looking tome, that includes 659 pages, 155 color range maps, 73 illustrations of species, and 16 color photos of Montana’s habitats. Upon the first bend of the binding, the reader will quickly realize the impressive depth of detail and research that went into writing and completing this book. Although Montana is the fourth largest state, one of the least populated states, and has few “binoculars on the ground,” the state has a fascinating and extensive ornithological history. The Birds of Montana is not a field guide, but rather it is an astonishingly comprehensive reference …


Review Of Estimation Of Parameters For Animal Populations: A Primer For The Rest Of Us By Larkin A. Powell And George A. Gale, Max Post van der Burg 2016 United States Geological Survey, Northern Prairie Wildlife Research Center

Review Of Estimation Of Parameters For Animal Populations: A Primer For The Rest Of Us By Larkin A. Powell And George A. Gale, Max Post Van Der Burg

The Prairie Naturalist

“Me? A modeler? Never!” This is the opening challenge of the book, Estimation of Parameters for Animal Populations: A Primer for the Rest of Us, by Larkin Powell and George Gale. I say “challenge” because I think this book attempts to challenge the misconception that quantitative methods are out of reach for most biologists and wildlife scientists. When many of us attend college or graduate school to study wildlife science there’s a sense that, at some point, there will be math. But it appears that the attitude of many students toward this reality is to simply suffer through the …


Efikasi Herbisida Oksifluorfen 240 G/L Untuk Mengendalikan Gulma Pada Budidaya Padi Sawah (Oryza Sativa L), Uum Umiyati 2016 Fakultas Pertanian, Universitas Padjadjaran

Efikasi Herbisida Oksifluorfen 240 G/L Untuk Mengendalikan Gulma Pada Budidaya Padi Sawah (Oryza Sativa L), Uum Umiyati

Jurnal Kultivasi

Tujuan dari percobaan ini adalah menguji keefektifan dari herbisida Oksifluorfen 240 g/l dalam mengendalikan gulma umum pada budidaya padi sawah sistem pindah tanam. Percobaan dilaksanakan di Balai Penelitian Pertanian Desa Barepan Kecamatan Plumbon Kabupaten Cirebon. Waktu pelaksanaan percobaan dimulai dari bulan Mei – Agustus 2016. Percobaan dilaksanakan dengan metode eksperimental dengan 7 perlakuan dan 4 ulangan, rancangan percobaan yang digunakan adalah Rancangan Acak Kelompok. Untuk menguji nilai tengah perlakuan yang berbeda digunakan uji lanjut Duncan pada tingkat kepercayaan 95 %. Perlakuan yang diujikan adalah herbisida Oksifluorfen 240 g/l dosis 1.2 l/ha, Oksifluorfen 240 g/l dosis 1.8 l/ha, Oksifluorfen 240 g/l …


Characterization Of Echinochloa Spp. In Arkansas, Hussain Tahir 2016 University of Arkansas, Fayetteville

Characterization Of Echinochloa Spp. In Arkansas, Hussain Tahir

Graduate Theses and Dissertations

Echinochloa species are the most problematic grass weeds in rice and soybean production throughout the southern United States. The species under this genus has high intra- and interspecific variability, with many ecotypes, observed within a species. This study was conducted to: i) characterize the morphology and phenology of Echinochloa accessions from Arkansas in a common garden; ii) verify the species identity of these accessions based on their morphological traits, and iii) evaluate the dormancy characteristics of Echinochloa accessions. Junglerice (E. colona) was identified as the most common species, comprising about 78% of the accessions collected, with barnyardgrass (E. crus-galli) and …


Over-Summering Ecology Of The Wheat Curl Mite (Aceria Tosichella Keifer), Anthony J. McMechan 2016 University of Nebraska-Lincoln

Over-Summering Ecology Of The Wheat Curl Mite (Aceria Tosichella Keifer), Anthony J. Mcmechan

Department of Entomology: Dissertations, Theses, and Student Research

The wheat-mite-virus complex is a consistent and significant threat to winter wheat production in the western Great Plains. This complex consists of three viruses (Wheat streak mosaic virus, Triticum mosaic virus, and Wheat mosaic virus that are transmitted by the wheat curl mite (Aceria tosichella Keifer). Yield impacts from this complex are typically associated with the presence of volunteer wheat that emerges prior to harvest as a result of hail occurring during the heading stages of wheat in early summer. Historical literature on pre-harvest germination has been primarily focused on accelerating breeding programs; however, critical gaps in knowledge exist on …


The Preservation And Protection Of Native Biodiversity In The Guadalupe Nipomo Dunes Complex, Lindsey M. Whitaker, Matthew Ritter, Scott J. Steinmaus, Jonathan Hall 2016 California Polytechnic State University, San Luis Obispo

The Preservation And Protection Of Native Biodiversity In The Guadalupe Nipomo Dunes Complex, Lindsey M. Whitaker, Matthew Ritter, Scott J. Steinmaus, Jonathan Hall

Master's Theses

The Guadalupe Nipomo Dunes Complex (GNDC) is located within the California Floristic Province, a biodiversity hotspot characterized by high rates of endemism and exceptional loss of habitat. In 1980, the US Fish and Wildlife Service described the GNDC as, “the most unique and fragile ecosystem in the State of California,” and ranked it first on a list of 49 habitat areas needing state protection. It is the largest coastal dune area in California and it is one of the last remaining, relatively intact ecosystems of its type and size in the western United States. The growing recognition of species decline …


Addressing The Needs Of Classical Biological Control Programs, Invasive Species Advisory Committee 2016 University of Nebraska - Lincoln

Addressing The Needs Of Classical Biological Control Programs, Invasive Species Advisory Committee

National Invasive Species Council

Conclusions

Classical biological control has been among the most cost- effective and environmentally safe management tools for invasive species for many years, both nationally and internationally. Addressing the political, regulatory, and institutional challenges in the discovery, pre-release phase and post-release monitoring of a classical biological control program would greatly enhance the long-term potential for success. From this white paper, a number of recommendations were developed that we believe will significantly improve prioritization and effectiveness of classical biological control programs, including:

1. Develop transparent criteria to prioritize those invasive species for which classical biological control is the most cost-effective control option. …


Book Reviews: A Chorus Of Cranes: The Cranes Of North America And The World. Paul A. Johnsgard (With Photographs By Thomas D. Mangelsen, And Drawings And Maps By Paul A. Johnsgard)., John G. Sidle 2016 Secretariat of the Pacific Regional Environment Programme

Book Reviews: A Chorus Of Cranes: The Cranes Of North America And The World. Paul A. Johnsgard (With Photographs By Thomas D. Mangelsen, And Drawings And Maps By Paul A. Johnsgard)., John G. Sidle

The Prairie Naturalist

Once again, naturalist and author Paul A. Johnsgard invites us to dance and chorus with cranes, and to appreciate their beauty and links to another species, Homo sapiens. A Chorus of Cranes is about natural history but also is a plea for conservation, which is a common foreword, prologue, preface, and/or epilogue of many wildlife books. It is vintage Paul Johnsgard text from preface to epilogue, words that emerge after a long wade through countless papers and reports, and a prolonged career of observation and reflection in the field. He has beckoned us before to cherish cranes and the natural …


Distribution Of Short-Tailed Shrews (Mammalia: Soricidae: Blarina) In Missouri, Russell S. Pfau, Aaron P. Figueroa 2016 Tarleton State University

Distribution Of Short-Tailed Shrews (Mammalia: Soricidae: Blarina) In Missouri, Russell S. Pfau, Aaron P. Figueroa

The Prairie Naturalist

Three species of short-tailed shrews (genus Bla- rina) occur throughout the eastern one-half of the United States and southern Canada. B. brevicauda is the most widely distributed, ranging from the Atlantic ocean to the western Great Plains. B. carolinensis occurs throughout the southeastern U.S., and B. hylophaga is found in the southern plains states. The current understanding of the geographic distributions of these species is based primarily on morphol- ogy; size is the primary characteristic used for identifica- tion with B. brevicauda the largest and B. carolinensis the smallest.

The only states in which all three species have been reported …


Resource Selection By Black-Backed Woodpeckers (Picoides Arcticus) And American Three-Toed Woodpeckers (P. Dorsalis) In South Dakota And Wyoming, Sean R. Mohren, Mark A. Rumble, Chadwick P. Lehman, Stanley H. Anderson 2016 Crater Lake National Park & University of Wyoming, Laramie

Resource Selection By Black-Backed Woodpeckers (Picoides Arcticus) And American Three-Toed Woodpeckers (P. Dorsalis) In South Dakota And Wyoming, Sean R. Mohren, Mark A. Rumble, Chadwick P. Lehman, Stanley H. Anderson

The Prairie Naturalist

Black-backed woodpeckers (Picoides arcticus, [BBWO]) and American three-toed woodpeckers (P. dorsalis, [ATTW]) are uncommon inhabitants of conifer forests and are sympatric in some areas, including the Black Hills. Both species exhibit genetic characteristics associated with isolated populations, are species of special management concern, and for which data are lacking concerning populations and habitats. We developed resource selection models of forest vegetation within 500 m radius plots (78.5 ha) for BBWOs and ATTWs to provide forest managers with stand-level information to estimate how forest management might affect habitat for these species in the Black Hills. Relative probability of selection by BBWOs …


Missing The Point, Christopher N. Jacques 2016 Western Illinois University

Missing The Point, Christopher N. Jacques

The Prairie Naturalist

Greetings GPNSS members! I hope summer finds you well and enjoying the Great Plains in some way, whether that be getting your hands dirty with field work, a reprieve from the office, anxiously awaiting the crappie bite at your favorite lake, or taking a much needed vacation. For those who enjoy cooler temperatures, summer heat and humidity are challenging and even the most seasoned field biologists among us are tested when fighting the conditions doing what we are passionate about. I personally prefer the fall and winter seasons, though also look forward to summer because it offers me a break …


The Science Of Open Spaces: Theory And Practice For Conserving Large, Complex Systems. Charles G. Curtin., Michelle L. Hellman, Caleb P. Roberts, Hannah Birge, Zachary Warren, Craig R. Allen 2016 University of Nebraska-Lincoln

The Science Of Open Spaces: Theory And Practice For Conserving Large, Complex Systems. Charles G. Curtin., Michelle L. Hellman, Caleb P. Roberts, Hannah Birge, Zachary Warren, Craig R. Allen

The Prairie Naturalist

The phrase “open spaces,” may bring to mind expansive tracts of prairie, rangeland, or even desert, stretching lonely and unchanged to the horizon. Open spaces also could conjure open oceans or interstitial rural lands between urbanized hubs, dotted with farms, fields, and woodlands. In an abstract sense, open spaces could represent gaps in human understanding or blank spaces on a map. In his book The Science of Open Spaces, landscape ecologist Charles Curtin combines all these perspectives, expanding the definition of “open spaces” to multi-layered and multi-scaled complex systems that are “greater than the sum of their parts.” He populates …


Isotopes From Fecal Material Provides Evidence Of Recent Diet Of Prairie Deer Mice, John W. Doudna, Brent J. Danielson 2016 Iowa State University

Isotopes From Fecal Material Provides Evidence Of Recent Diet Of Prairie Deer Mice, John W. Doudna, Brent J. Danielson

The Prairie Naturalist

Prairie deer mice are important predators in many agricultural systems, and through their diet they can help to regulate pest insect and weed populations. Our objective was to test whether fecal material is an effective means of detailing the foraging ecology of small mammals. We conducted three studies to evaluate the efficacy of this technique: 1) field-collected fecal material from unknown deer mice from late winter to early spring, 2) fecal material collected in an enclosure with mice fed a mix of C3 and C4 plant seeds, and 3) fecal material from tagged female mice in the field. We detected …


Book Review: Better Birding: Tips, Tools, And Concepts For The Field. George L. Armistead And Brian L. Sullivan., Stephen J. Dinsmore 2016 Iowa State University, Ames

Book Review: Better Birding: Tips, Tools, And Concepts For The Field. George L. Armistead And Brian L. Sullivan., Stephen J. Dinsmore

The Prairie Naturalist

George Armistead and Brian Sullivan have written a book whose aim is to provide birders with a solid foundation upon which to develop better birding skills. They advocate a more holistic approach to bird identification than simply looking at a set of predetermined field marks. To that end, their approach combines traditional field identification approaches with behavioral and habitat cues, as well as natural history, to broaden bird identification skills. This is not the first book to make a case for looking at bird identification more broadly, although their specific approach seems unique. The authors offer constructive criticism of “traditional” …


Mink Predation Of Brown Trout In A Black Hills Stream, Jake Davis, Jerry W. Wilhite, Steven R. Chipps 2016 South Dakota Department of Game, Fish and Parks

Mink Predation Of Brown Trout In A Black Hills Stream, Jake Davis, Jerry W. Wilhite, Steven R. Chipps

The Prairie Naturalist

In the early 2000’s, declines in the brown trout (Salmo trutta) fishery in Rapid Creek, South Dakota, caused concern for anglers and fisheries managers. We conducted a radio telemetry study in 2010 and 2011 to identify predation mortality associated with mink, using hatchery-reared (2010) or wild (2011) brown trout. Estimated predation rates by mink (Mustela vison) on radio-tagged brown trout were 30% for hatchery fish and 32% for wild fish. Size frequency analysis revealed that the size distribution of brown trout lost to predation was similar to that of other, radio-tagged brown trout. In both years, a higher proportion of …


Evaluating The Myth Of Allelopathy In California Blue Gum Plantations, Kristen Marie Nelson 2016 California Polytechnic State University, San Luis Obispo

Evaluating The Myth Of Allelopathy In California Blue Gum Plantations, Kristen Marie Nelson

Master's Theses

It is widely accepted that allelopathy is not only significant, but more or less singular, in the inhibition of understory vegetation in California Eucalyptus globulus (blue gum) plantations. However, there is no published documentation of allelopathy by blue gums against California native species. Here, we present evidence that germination and early seedling growth of five California native species are not inhibited by chemical extracts of blue gum foliage, either at naturally-occurring or artificially concentrated levels. In the greenhouse, seeds were germinated in field-collected soil from mature blue gum plantations and the adjacent native, coastal scrub communities. In petri plates, seeds …


Fixed Versus Random Sampling Designs In Small South Dakota Glacial Lakes, Bradley J. Smith, Nathan S. Kruger, Nicholas S. Voss, Brian G. Blackwell 2016 South Dakota State University

Fixed Versus Random Sampling Designs In Small South Dakota Glacial Lakes, Bradley J. Smith, Nathan S. Kruger, Nicholas S. Voss, Brian G. Blackwell

The Prairie Naturalist

Choice of sampling design is fundamental when planning surveys to monitor fisheries resources. However, little is known about the impact that different sampling designs may have on commonly collected fish population metrics used to index relative abundance, size structure, and diversity in small (<200 ha) glacial lakes. To address this issue, we sampled three small glacial lakes in eastern South Dakota with modified fyke nets and gill nets at fixed sites used by South Dakota Game, Fish and Parks and a complement of nets at randomized sites. Catch per unit effort (CPUE), proportional size distribution (PSD), and PSD-preferred (PSD-P) were compared between fixed and random designs for each species and gear by lake while Bray-Curtis distances were calculated between sample designs for each gear type in each lake. Precision of CPUE estimates for routinely indexed species were calculated for both gears used by each sampling design. No consistent bias in calculated population metrics was detected between sampling designs for any species collected with either gear type in the three lakes. Sampling precision of CPUE estimates were low for both gears and study designs; though randomized sites tended to yield lower precision. Power analyses indicated that current levels of sampling effort are insufficient to detect differences in CPUE or PSD/PSD-P between fixed and random sampling designs. In addition to being small, study lakes had relatively homogenous habitat allowing for effective sampling resulting in similar values of CPUE and PSD/PSD-P for both fixed and random study designs, and high assemblage overlap. We conclude that fixed sampling sites provide adequate representation of fish communities in small glacial lakes and are sufficient for monitoring temporal changes in these small, but numerous, systems.


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