Weed Science Commons^™

Effects Of Short-Term Soil Conditioning By Cheatgrass And Western Wheatgrass, James J. O'Connor, Janet S. Prevey

The Prairie Naturalist

The exotic grass Bromus tectorum (cheatgrass) is a ubiquitous invader in the western USA. Cheatgrass is a proficient competitor, frequently displacing native plants, forming monotypic stands and reducing biodiversity in ecosystems it invades. Our experiment tested whether short-term soil modification by cheatgrass and a predominant native grass, Pascopyrum smithii (western wheatgrass), affected subsequent growth of both species. We compared productivity of cheatgrass and western wheatgrass by harvesting aboveground biomass of plants grown in either cheatgrass- or western wheatgrass-conditioned soils over two simulated growing seasons. Results indicated that cheatgrass soils do not inhibit the productivity of the native grass, but do …

North Shore: A Natural History Of Minnesota’S Superior Coast, Janet R. Koeugh

The Prairie Naturalist

Many readers of The Prairie Naturalist have lived along or visited Lake Superior’s coast. Like me, you have probably wondered about the geology and history of this beautiful and dramatic feature of northeastern Minnesota. Chel Anderson and Adelheid Fischer have written an accessible book that comprehensively describes the history and geology of the coast, surrounding highlands, and Lake Superior itself. In addition, the authors have provided fascinating subchapters on some of the most interesting species that are key elements of the region.

This rather large but beautiful book is arranged in five major chapters that cover the dominant geological units …

Remembering Paul B. Kannowski, Robert Seabloom

The Prairie Naturalist

I am saddened to report that Dr. Paul Kannowski passed away 3 September 2015, succumbing to cancer. He was 88. A native of Grand Forks, Paul attended the University of North Dakota for his B.S. and M.S. degrees, and the University of Michigan for his Ph.D. He joined the University of North Dakota Biology Department in 1957, retiring in 1990 after 33 years of service

Paul chaired UND’s Biology Department twice, totaling 13 years, considered to be a remarkable achievement by many of us who have been exposed to that task! His leadership was instrumental in the nearly exponential growth …

Variability In The Selection Patterns Of Pronghorn: Are They Really Native Prairie Obligates?, Paul F. Jones, Mike Grue, Mike Suitor, Darren J. Bender, Cormack Gates, Dale Eslinger, Julie Landry-Deboer

The Prairie Naturalist

In Canada, pronghorn (Antilocapra americana) are primarily considered a native prairie obligate because of their reliance on open grassland vegetation communities, although an assessment of local ecological knowledge suggests that pronghorn in Alberta select a variety of habitat from native prairie to cultivated lands. The primary objective of our study was to assess whether pronghorn in Alberta and Saskatchewan are native prairie obligates. Specifically, we addressed the following questions: 1) do individual pronghorn show similar selection patterns for native prairie and, therefore, support the notion that they are prairie obligates; 2) do pronghorn show consistent resource selection patterns …

Remembering The Days Of Old: Data Exploration And Simple Statistics, Christopher N. Jacques

The Prairie Naturalist

Greetings GPNSS members! By the time you read this editorial, most of you will probably be enjoying spectacular seasonal changes in the outdoors this autumn and a hint of winter in the air (for those of us in the northern Great Plains region). I write this editorial during my favorite time of year, deer hunting in the Midwest. Temperatures are finally start- ing to resemble the fall and the Christmas Holiday season is just around the corner. Much like my children have images of Santa dancing in their heads on Christmas Eve, each fall I replay images of a trophy …

Notes: Woodpecker Forage Availability In Habi- Tat Disturbances Of The Black Hills, Brian E. Dickerson, Angie K. Ambourn, Mark A. Rumble, Kurt K. Allen, Chad P. Lehman

The Prairie Naturalist

Habitat disturbance events are critical to ecological systems in which some bird species have become specialized. The vegetation community, reduced competition, ability to avoid predators, nest-site characteristics, and forage opportunities within a disturbed ecosystem are all aspects that make it desirable for selection by particular species (Svärdson 1949, Cody 1981, Martin 1998). Specifically, avian species rely on the forest conditions created by fire, insects, and disease (Brawn et al. 2001, Hunter et al. 2001, Devictor et al. 2008). In the Black Hills National Forest (BHNF) of South Dakota,two major types of natural disturbances include wildfires and mountain pine beetle (Dendroctonus …

Estimating Herbaceous Biomass Of Grassland Vegetation Using The Reference Unit Method, Eric D. Boyda, Jack L. Bulter, Lan Xu

The Prairie Naturalist

Aboveground net primary production provides valuable information on wildlife habitat, fire fuel loads, and forage availability. Aboveground net primary production in herbaceous plant communities is typically measured by clipping aboveground biomass. However, the high costs associated with physically harvesting plant biomass may prevent collecting sufficient data to account for natural spatial and temporal variability of vegetation at a landscape scale. Various double-sampling techniques have been developed to increase sample size while reducing cost. We applied a biomass estimation technique previously developed for estimating shrub biomass using representative samples or “reference units” to estimate herbaceous grassland biomass. Our reference units consisted …

Use Of Hppd-Inhibiting Herbicides For Control Of Common Weeds In Arkansas And Current Status Of Herbicide-Resistance Among Echinochloa Populations In Arkansas, Clay Starkey

Graduate Theses and Dissertations

Herbicide-resistant weeds in Arkansas cause problems for growers. Up-to-date information and new technologies can help plan mitigation strategies to slow resistant weeds. The objectives of this research were to provide a ‘snapshot’ of herbicide-resistant Echinochloa spp. in rice producing counties, determine how much resistance has spread across the state, and understand the effectiveness of 4-hydroxyphenylpyruvate dioxygenase (HPPD)-inhibiting herbicides for control of glyphosate-resistant (GR) Palmer amaranth relative to commercial standards currently labeled in soybean. To assess the prevalence of Echinochloa spp. resistance, 82 samples were collected from 23 rice producing counties in 2010. The samples were tested for resistance to commonly …

Sage-Grouse Nests In An Active Conifer Mastication Site, Charles P. Sandford, David K. Dahlgren, Terry A. Messmer

The Prairie Naturalist

Greater sage-grouse (Centrocercus urophasianus; sage-grouse) have experienced long-term range-wide population declines and now may occupy less than 50% of their historic range (Schroeder et al. 2004). Conifer encroachment into sagebrush (Artemisia spp.) habitat was identified as a major conservation threat by the United States Fish and Wildlife Service (USFWS) as the agency reviewed the listing status of the species for possible protection under the Endangered Species Act of 1973 (USFWS 2013).

Conifer encroachment into sagebrush habitats negatively impacts sage-grouse at landscape scales (Doherty et al. 2008, Casazza et al. 2011, Baruch-Mordo et al. 2013). Sage-grouse will utilize …

North Shore: A Natural History Of Minnesota’S Superior Coast, Janet R. Keough

The Prairie Naturalist

Many readers of The Prairie Naturalist have lived along or visited Lake Superior’s coast. Like me, you have probably wondered about the geology and history of this beautiful and dramatic feature of northeastern Minnesota. Chel Anderson and Adelheid Fischer have written an accessible book that comprehensively describes the history and geology of the coast, surrounding highlands, and Lake Superior itself. In addition, the authors have provided fascinating subchapters on some of the most interesting species that are key elements of the region.

This rather large but beautiful book is arranged in five major chapters that cover the dominant geological units …

Distribution And Occurrence Of Bat Species In North Dakota, Josiah J. Nelson, Paul R. Barnhart, Erin H. Gillam

The Prairie Naturalist

Prior to 2009, a detailed survey of occurrence and distribution of bats in North Dakota had not been conducted. Localized surveys, occurrence reports, and museum specimens provided the only records of bats in the state. Ongoing habitat loss, exploitation of natural resources, and the impending spread of white-nose syndrome to the western United States are major threats to bat populations of the region. The objective of this study was to document presence and distributions of bat species resident in North Dakota. From 2009 to 2012, multiple mist-netting and acoustic surveys were conducted to document species presence across North Dakota. A …

Variation Between Peripheral And Center Achene Morphology And Attributes Of Achene Germination In The Invasive Species, Centaurea Melitensis, Kandee Bain

Electronic Theses, Projects, and Dissertations

Invasive species are often successful and problematic because of their ability to persist in disturbed and undisturbed environments despite weed management practices. Understanding reproduction and dispersal strategies in these species can aid in developing management approaches to help control their spread. Centaurea melitensis, a nonnative invasive with European origins, is found in disturbed areas of southern California. It produces three different types of flower heads that develop at different times and at different locations on the plant during the growing season. The chasmogamous (CH) flower heads are located at the top of the plant, the initial cleistogamous (iCL) heads …

Predicting Invasive Range Of Eucalyptus Globulus In California, Anthony J. Lopez

Master's Theses

Eucalyptus globulus is the subject of intense debate in California. Its invasive potential, aggressive growth, reproductive biology, and association with fire make the prediction of spread important in California. Two modeling simulations, Climex and Maxent, will illustrate the distribution and potential growth range of E. globulus in California based on climate and presence. Modeling the potential range of growth will predict invasive spread. The anticipated result is the continued spread of E. globulus in coastal regions with adequate moisture and suitable climate. Predicting the range of E. globulus in California dictates management strategy and is key for preventing further introduction, …

Canola: A Modern Crop For A Modern Era, Kenneth J. Roché

Doctor of Plant Health Program: Dissertations and Student Research

The University of Nebraska-Lincoln Doctor of Plant Health program is a professional doctorate program with a comprehensive approach to plants and agriculture. The program emphasizes a broad interdisciplinary education across all plant-related disciplines, practical learning, research, and experience through internships. For my final required internship, I worked as a senior agricultural research intern with Research Designed for Agriculture (RD4AG) in Montana. RD4AG is a contract research organization based in Yuma, AZ with over thirty-years of experience. During my three month internship at RD4AG in Montana, a large portion of my responsibilities centered on managing regulated canola trials that were undertaken …

Enhancing The Effectiveness Of Biological Control Programs Of Invasive Species By Utilizing An Integrated Pest Management Approach, Invasive Species Advisory Committee

National Invasive Species Council

Conclusion

Biological control has been shown on many occasions to be the most cost-effective invasive species management tool available. However, integrating biological control projects with the full breadth of other integrated pest management (IPM) tools, expanding post-re- lease monitoring to maximize efficacy, adaptive management, and incorporating new and innovative ecological, and genetic technologies may provide private and public land managers greater opportunities for long-term success in suppression of established invasive species.

Pengaruh Keberadaan Gulma (Ageratum Conyzoides Dan Boreria Alata) Terhadap Pertumbuhan Dan Hasil Tiga Ukuran Varietas Kedelai (Glycine Max L. Merr) Pada Percobaan Pot Bertingkat, Abdul Karim Kilkoda, Tati Nurmala, Dedi Widayat

Jurnal Kultivasi

Percobaan dilaksanakan di rumah kaca Fakultas Pertanian Universitas Padjadjaran, Jati-nangor, Kabupaten Sumedang, Jawa Barat. Tujuan dari penelitian ini adalah untuk menguji eksudat akar yang terdapat pada gulma Ageratum conyzoides dan Borreria alata terhadap pertumbuhan dan hasil tanaman kedelai. Percobaan dilakukan mulai dari bulan Oktober 2014 sampai dengan bulan Desember 2014 dengan menggunakan rancangan acak kelompok pola faktorial. Faktor perlakuan pertama adalah jenis gulma terdiri dari 3 taraf antara lain gulma A. Conyzoides, gulma B. alata dan tanpa gulma (kontrol). Perlakuan kedua adalah ukuran benih varietas kedelai yang terdiri dari 3 taraf. Total kombinasi perlakuan adalah 9 kombinasi perlakuan, dengan 3 …

Pengaruh Dosis Herbisida Glifosat Terhadap Gulma, Pertumbuhan, Dan Hasil Tiga Kultivar Kedelai (Glycine Max (L.) Pada Sistem Tanpa Olah Tanah (Tot), Dedi Widayat, R. Ganilda Yustisiyanika

Jurnal Kultivasi

Penelitian ini bertujuan untuk mengetahui pengaruh interaksi antara dosis herbisida Glifosat dan kultivar kedelai terhadap gulma, pertum-buhan, dan hasil tanaman kedelai. Percobaan dilakukan di Kebun Percobaan Saung Meeting Ciparanje Universitas Padjadjaran Jatinangor, Kabupaten Sumedang. Rancangan percobaan yang digunakan adalah rancangan acak kelompok pola faktorial yang terdiri dari dua faktor dan diulang 3 kali. Faktor yang pertama adalah kultivar kedelai yang tediri dari tiga yaitu kultivar Tidar, Burangrang, dan Slamet. Faktor yang kedua dosis herbisida glifosat yang terdiri dari 3 taraf yaitu 1,5l/ha, 3l/ha, dan 4,5l/ha. Kombinasi perlakuan kultivar dan dosis herbisida glifosat tidak memberikan pengaruh interaksi terhadap bobot kering gulma …

Pengaruh Pemberian Zat Retardan Terhadap Pertumbuhan Dan Hasil Ubi Pada Dua Kultivar Kentang (Solanum Tuberosum L.) Di Dataran Medium, Sumadi, Erni Suminar, Murgayanti, Anne Nuraini

Jurnal Kultivasi

Tujuan dari kegiatan penelitian ini adalah untuk mendapatkan informasi mengenai kulti-var kentang dan jenis serta konsentrasi zat retardan yang dapat mendukung pertumbuhan dan perkembangan serta kuantitas dan kualitas hasil ubi bibit kentang di dataran medium. Metode penelitian yang digunakan adalah Rancangan Petak terpisah. Perlakuan terdiri dari petak utama yaitu kultivar yaitu kultivar Nadia dan Granola, dan anak petak yaitu jenis dan konsentrasi zat retardan dengan penggunaan paklobutrazol ( 0; 40; 120 mg L-1 ) atau coumarin (45; 90; 135 mg L-1). Hasil percobaan menun-jukkan bahwa jenis kultivar dan zat retardan berpengaruh terhadap pertumbuhan dan per-kembangan bibit kentang. Terjadi interaksi pada …

Assessing Multiple-Herbicide Resistance In A 2,4-D Resistant Waterhemp (Amaranthus Tuberculatus) Biotype From Nebraska: Student Research, Roberto Crespo

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

A waterhemp biotype was recently reported resistant to 2,4-D in Nebraska. In addition to the repeated use of 2,4-D, atrazine and imazathapyr were reported to be frequently used to control broadleaf weeds. Greenhouse experiments were conducted to confirm 2,4-D resistance and test for resistance to growth regulator herbicides and other herbicide modes-of-action (MoA). A single dose-response experiment showed reduced sensitivity in all three waterhemp biotypes to atrazine, imazethapyr and lactofen; therefore, they were generally considered resistant to those three herbicide MoA. None of the biotypes contained the Ser264 target-site mutation. Since the ametryn dose-response experiment resulted in all susceptible biotypes, …

When An Invasive Plant Fails To Invade, Stephen L. Young

West Central Research and Extension Center, North Platte

In 2012, much of the US Midwest was gripped in one of the most severe droughts on record. While conducting experimental fieldwork at a site in Nebraska during June of that year, I noticed a single musk thistle (Carduus nutans; Figure 1) that appeared to be in the bolt or early flowering stage, which is typical for the species at that time. Here, however, two things were unusual: this plant was less than 1 meter tall (with adequate moisture and light, musk thistle typically grows to heights of 1–2.5 meters before flowering), and was only 3 months old (the bolt …