Weed Science Commons^™

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 …

Assessing Genetic Variation Of Rocky Mountain Bighorn Sheep At Elk Mountain, Brynn L. Parr, Rebeca L. Juarez, Jonathan A. Jenks

The Prairie Naturalist

The bighorn sheep (Ovis canadensis canadensis) herd occupying the Elk Mountain Region of South Dakota and Wyoming was established in 2001 with 20 individuals. An additional 7 ewes were released in 2004. The population increased to approximately 120 individuals in 2009, but subsequently declined to an estimated 80 individuals. Because of the low population size used to establish the herd and relative isolation of the Elk Mountain Region, potential factors associated with the population decline included reduced genetic diversity. Our objectives were to: 1) assess genetic diversity, 2) measure effective population size (Ne), and 3) compare the genetic diversity of …

Keys To Lichens Of North America, Revised And Expand- Ed. Irwin M. Brodo (Photographs By Sylvia Duran Sharnoff And Stephen Sharnoff; Drawings By Susan Laurie-Bourque)., Caleb A. Morse

The Prairie Naturalist

It would be hard to overestimate the importance of the 2001 publication of Lichens of North America (hereafter LNA) by Irwin Brodo, Silvia Duran Sharnoff, and Stephen Sharnoff (Brodo et al. 2001). Beautifully illustrated, LNA included both an excellent overview to lichenology—including such diverse topics as chemistry, ecology, ethnolichenology, and specimen preparation—and descriptions of more than 800 of the common and charismatic lichens of North Ameri- ca. It is the rare book that provides a good introduction to the discipline, while serving as an essential tool for lichenologists. LNA is frequently cited in journals as an authoritative source on spot …

Varmints And Victims: Predator Control In The Ameri- Can West. Frank Van Nuys., Phil Mastrangelo

The Prairie Naturalist

Having recently retired after 30+ years working in the field of human-wildlife conflicts, including predator conflicts with livestock, I looked forward to reading Varmints and Victims: Predator Control in the American West by Frank Van Nuys. As a wildlife biologist with an interest in the history of wildlife management in North America, I was further intrigued by the subject matter selected by Van Nuys.

In the book’s introduction, Van Nuys explains how the issue of mountain lion (Puma concolor) management in his home state of South Dakota sparked his interest in further exploring the history of predators and their management …

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.

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 …

Notes: Comparisons Of Catch Between Two Bait Types With An Emphasis On Pallid Stur- Geon, Thad W. Huenemann, Kirk D. Steffensen

The Prairie Naturalist

Trotline sampling has been a common practice used by commercial and recreational anglers to target specific fish species (e.g. Ictaluridae and Acipenseridae), while biologists have used them as a management tool to monitor and evaluate fish populations (Graham 1997, Vokoun and Rabeni 1999, Arterburn and Berry 2002, Steffensen et al. 2011). Different trotline configurations have been evaluated to determine which combination of hook type and bait produces higher catch rates for catfish species (Johnson 1987, Arterburn and Berry 2002) but this information is lacking for sturgeon species. For example, Arterburn and Berry (2002) concluded that channel catfish (Ictalurus punctatus) were …

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 …

Analyzing The Phenologic Dynamics Of Kudzu (Pueraria Montana) Infestations Using Remote Sensing And The Normalized Difference Vegetation Index., Faye Peters

Electronic Theses and Dissertations

Non-native invasive species are one of the major threats to worldwide ecosystems. Kudzu (Pueraria montana) is a fast-growing vine native to Asia that has invaded regions in the United States making management of this species an important issue. Estimated normalized difference vegetation index (NDVI) values for the years 2000 to 2015 were calculated using data collected by Landsat and MODIS platforms for three infestation sites in Kentucky. The STARFM image-fusing algorithm was used to combine Landsat- and MODIS-derived NDVI into time series with a 30 m spatial resolution and 16 day temporal resolution. The fused time series was …

Cover Crop Mixture Diversity And Function, Angela Florence

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

The objective of this study was to evaluate the effect of cover crop mixture diversity on cover crop function. Specifically, this study evaluated the effect of cover crop species and functional richness on aboveground biomass productivity, weed suppression, soil nutrient retention, soil microbial community characteristics, and performance stability. Twenty to forty cover crop treatments were replicated three to four times at eleven sites across southeastern Nebraska using a pool of eighteen species representing three cover crop species each from six pre-defined functional groups: cool-season grasses, cool-season legumes, cool-season brassicas, warm-season grasses, warm-season legumes, and warm-season broadleaves. Each species was planted …

Biology, Gene Flow, And Management Of Glyphosate-Resistant Common Waterhemp (Amaranthus Rudis Sauer) In Nebraska, Debalin Sarangi

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

Common waterhemp is the most troublesome weed in the midwestern United States. Growers from Nebraska reported failure to control common waterhemp following sequential applications of glyphosate in glyphosate-tolerant corn and soybean, which led to moderate to severe yield loss; justifying the need to confirm resistance and study the biology and management of common waterhemp. The objectives of this research were: 1) to confirm the presence of glyphosate-resistant (GR) common waterhemp biotypes in Nebraska and to evaluate their sensitivity to herbicides belonging to alternative sites-of-action; 2) to evaluate the response of common waterhemp to water stress; 3) to quantify pollen-mediated gene …

Studi Efektivitas Herbisida Oksifluorfen 240 Gl-1 Sebagai Pengendali Gulma Pada Budidaya Bawang Merah (Allium Ascalonicum L.), Uum Umiyati

Jurnal Kultivasi

Penelitian lapangan bertujuan untuk mengetahui efektivitas herbisida berbahan aktif Oksifluorfen 240 gL-1. Sebagai pengendali gulma umum pada tanaman bawang merah. Percobaan dilakukan di desa Cikuya kecamatan Banjarharjo kabupaten Brebes dari bulan Oktober – Desember 2015. Rancangan percobaan yang digunakan adalah rancangan acak kelompok dengan 4 ulangan dan 7 perlakuan. Perlakuan terdiri dosis herbisida oksifluorfen 240 gaiL-1dengan dosis 1,00; 1,50; 2,00; 2,50 dan 3,00 l/hektar, penyiangan secara manual dan tanpa pengendalian herbisida maupun penyiangan (kontrol). Hasil penelitian menunjukkan bahwa herbisida oksifluorfen 240 gaiL-1 dengan dosis 1,5–3 l/ha efektif mengen-dalikan gulma dominan tanaman bawang merah seperti Cynodon dactylon, Echinocloa colona, Cyperus iria …

Respons Tanaman Jagung (Zea Mays L.) Toleran Herbisida Akibat Pemberian Berbagai Dosis Herbisida Ipa Glifosat 486 G/L, Agus Wahyudin, Fiky Yulianto Wicaksono, D. F. Sari

Jurnal Kultivasi

Jagung merupakan salah satu serealia yang strategis di Indonesia. Jagung mempunyai peluang untuk dikembangkan karena fungsinya sebagai bahan pangan utama dan sebagai sumber bahan pakan ternak. Penggunaan tanaman jagung PRG toleran herbisida glifosat diharapkan dapat mengurangi penurunan hasil tanaman jagung. Penelitian ini bertujuan untuk mengetahui pengaruh pemberian berbagai dosis herbisida glifosat terhadap pertumbuhan dan hasil tanaman jagung (Zea mays L.) PRG toleran herbisida glifosat. Penelitian dilaksanakan di Kebun Percobaan Ciparanje Fakultas Pertanian Universitas Padjadjaran, kecamatan Jatinangor, kabupaten Sumedang, Jawa Barat pada bulan Desember 2014 hingga April 2015. Rancangan percobaan yang digunakan adalah Rancangan Acak Kelompok (RAK) dengan 8 perlakuan dan …

Evolutionary Explanation For Invasive Abilities Of Centaurea Stoebe (Spotted Knapweed) In Introduced Areas, Erin Koren

UReCA: The NCHC Journal of Undergraduate Research and Creative Activity

Since every invasion and every exotic species presents a new challenge with novel invasion strategies, the invasion of Centaurea stoebe (synonymously referred to as C. maculosa) into North America will be used as a case study to deeply examine invasion strategies. Centaurea stoebe is a short-lived (approximately 3 years) perennial member of the aster family (Broz et al., 2007). It occurs in two different cytotypes, or with two different chromosomal factors. In its home range, it exists in both diploid and tetraploid cytotypes, but only the tetraploid version is present in introduced ranges in North America (See Figure 1; Treier …

Review Of Following The Wild Bees: The Craft And Science Of Bee Hunting By Thomas D. Seeley, Katrina Klett

The Prairie Naturalist

Since the media’s coverage of the sudden losses of worker bee populations in many honeybee colonies during the winter of 2006-07 (a phenomenon that was later termed the Colony Collapse Disorder or CCD), there have been increasingly high levels of popular interest in bees and beekeeping in the United States. While a number of books have followed this wave of interest, Following the Wild Bees: The Craft and Science of Bee Hunting by Thomas Seeley is a fundamentally unique contribution to popular honeybee literature. The focus of the book is not on the current synergy of effects that are leading …

The Relationship Between Invasive Annual Grasses And Biological Soil Crust Across Eastern Washington, Jarrett B. Cellini

EWU Masters Thesis Collection

Invasive annual grasses cause ecological and economic damage across the western US and are a focal point in restoration and management plans. Managing invasion resistance of natural areas is critical to maintaining their biodiversity and function. Climate change is expected to shift species interactions, including invasive annual grasses, and may alter invasion resistance. One component of invasion resistance is biological soil crust (biocrust), which has been shown to limit Bromus tectorum (cheatgrass) in arid regions. However, biocrust has been less studied in semiarid regions and its effects on other invasive annual grasses, such as Ventenata dubia, have never been studied. …

Morphologic And Transcriptomic Response To Weed Pressure In Multiple Maize (Zea Mays L.) Selections And Teosinte (Zea Mays L. Ssp Parviglumis) Lines, Stephanie A. Bruggeman

Electronic Theses and Dissertations

Sweet corn (Zea mays L. convar. saccharata var. rugosa) and modern dent variants (field maize, Zea mays L. indentata) have varying degrees of weed tolerance (ability to maintain yield under weed stress). Maize retains ~30% of its ancestral teosinte’s (Zea mays ssp parviglumis) genetic base. Transcriptomic response to weed pressure in maize and teosinte can lead to manipulation of the maize genome to minimize crop yield loss due to weed presence. In maize and teosinte under weed-free and weedstressed conditions, the objectives of this study were: 1) to evaluate transcriptomic responses of 2 teosinte lines; 2) …

Evaluation Of Flame Weeding In Southeastern South Dakota, Benjamin William Arlt

Electronic Theses and Dissertations

Weed management is the main yield-limiting factor in production of organic crops. Currently, organic producers have limited resources available for in-row weed management. Flame weeding has been recognized for its potential as one part of an integrated approach at weed management in organic systems. Flame weeding uses propane fueled torches to heat plant tissue and denature proteins, thus injuring or destroying the affected tissue. When properly timed, flame weeding can effectively be used for weed control in corn and soybean fields. Corn and soybean have both shown tolerances to flame weeding and minimal yield loss with well-managed and timed flame …

Corncob Grit Application As An Alternative To Control Weeds In Two Crop Production Systems, Mauricio Erazo-Barradas

Electronic Theses and Dissertations

Weed management is one of the most challenging production problems in organic cropping systems because of limited weed control methods. Grits, derived from agricultural residues, have been demonstrated to control weed seedlings selectively in corn. This research examined weed efficacy and crop yield of an integrated air-propelled abrasive corncob grit (for in-row weed control) at varying timings and frequencies and flame-weeding or cultivation (for between-row weed control) system in two corn production systems. In the first study efficacy of weed control was assessed with this approach in an organic corn silage production system established in Morris, MN in 2013 and …

Plant Functional Trait And Hyperspectral Reflectance Responses To Comp B Exposure: Efficacy Of Plants As Landmine Detectors, Paul V. Manley Ii

Theses and Dissertations

At least 110 million landmines have been planted since the 1970s in about 70 nations, many of which remain in place today. Some risk of detection may be mitigated using currently available remote sensing techniques when vegetation is present. My study focused on using plants as phytosensors to detect buried explosives. I exposed three species representing different functional types (Cyperus esculentus (sedge), Ulmus alata (tree), Vitis labrusca (vine)) to 500 mg kg^-1 of Composition B (Comp B; 60/40 mixture of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and 2,4,6-trinitrotoluene (TNT)), a commonly used explosive mixture, and measured functional traits and reflectance over …