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Relationships Among Walleye Mercury, Selenium, Stable Isotopes, Size And Age, Mark J. Fincel, Robert P. Hanten, Shannon Minerich 2013 South Dakota Department of Game, Fish and Parks

Relationships Among Walleye Mercury, Selenium, Stable Isotopes, Size And Age, Mark J. Fincel, Robert P. Hanten, Shannon Minerich

The Prairie Naturalist

Bioaccumulation of mercury is well-documented in aquatic ecosystems and occurs as mercury is accumulated and passed up food chains (Kidd et al. 1995, Atwell et al. 1998, Downs et al. 1998). Trophic level correlations have been widely reported for mercury (Snodgrass et al. 2000) and other metals (Barron 1995). Generally, within a system, carnivores have the highest mercury loadings, omnivores intermediate and herbivores the lowest (Phillips et al. 1980). However, little research has focused on the differences in mercury bioaccumulation for a single species that ranges across multiple trophic levels (Burger et al. 2001).

Stable isotope analysis has expanded the ...


Associations Between Iron Concentration And Productivity In Montane Streams Of The Black Hills, South Dakota, Cari-Ann Hayer, Benjamin M. Holocmb, Steven R. Chipps 2013 South Dakota State University

Associations Between Iron Concentration And Productivity In Montane Streams Of The Black Hills, South Dakota, Cari-Ann Hayer, Benjamin M. Holocmb, Steven R. Chipps

The Prairie Naturalist

Iron is an important micronutrient found in aquatic systems that can influence nutrient availability (e.g. phosphorus) and primary productivity. In streams, high iron concentrations often are associated with low pH as a result of acid mine drainage, which is known to affect fish and invertebrate communities. Streams in the Black Hills of South Dakota are generally circumneutral in pH, yet select streams exhibit high iron concentrations associated with natural iron deposits. In this study, we examined relationships among iron concentration, periphyton biomass, macroinvertebrate abundance, and fish assemblages in four Black Hills streams. The stream with the highest iron concentration ...


Whooping Cranes Consume Plains Leopard Frogs At Migratory Stopover Sites In Nebraska, Keith Geluso, Brad T. Krohn, Mary J. Harner, Michael J. Assenmacher 2013 University of Nebraska at Kearney

Whooping Cranes Consume Plains Leopard Frogs At Migratory Stopover Sites In Nebraska, Keith Geluso, Brad T. Krohn, Mary J. Harner, Michael J. Assenmacher

The Prairie Naturalist

Whooping cranes (Grus americana) currently consist of a single, wild population that migrates annually from breeding grounds at Wood Buffalo National Park, Canada, to wintering grounds on and around the Aransas National Wildlife Refuge along the Texas coast, USA (NRC 2005). This population reached a low of less than 20 individuals in 1941 (Allen 1952) but has rebounded to over 250 individuals (Chavez-Ramirez and Wehtje 2012, Gil-Weir et al. 2012). Whooping cranes migrate approximately 4,000 km each spring and autumn, traversing much of the North American Great Plains (Lewis 1995) and periodically landing along rivers, wetlands, and other shallow ...


Sources Of Variability In Agronomic Weed Seed Predation: Time, Space, Habitat, And Hyperpredation, Sonja K. Birthisel 2013 The University of Maine

Sources Of Variability In Agronomic Weed Seed Predation: Time, Space, Habitat, And Hyperpredation, Sonja K. Birthisel

Electronic Theses and Dissertations

Weed seed predation is an ecosystem service that benefits farmers by decreasing seedbank inputs, thereby reducing weed pressure in subsequent growing seasons. Seed predation can be considerable, but is highly variable. Sources of variability may include time, space, habitat, and trophic interactions such as hyperpredation. Two experiments were conducted to measure the impacts of these sources of variability on weed seed predation rates in Maine mixed vegetable agroecosystems.

Chapter One of this thesis describes a series of landscape-level field experiments conducted to quantify the effects of time, space, and habitat on seed predation rates. Seed assays, with and without vertebrate ...


Impact Of Mid-Successional Dominant Species On The Diversity And Progress Of Succession In Regenerating Temperate Grasslands, Sandor Bartha, Szilard Szentes, Andras Horvath, Judit Hazi, Zita Zimmerman, Csaba Molnar, Istvan Dancza, Katalin Margoczi, Robert Pal, Dragica Purger, David Schmidt, Miklos Ovari, Cecelia Komoly, Zsuszanna Sutyinszki, Gabor Szabo, Andras Istvan Csatho, Melinda Juhasz, Karoly Penksza, Zsolt Molnar 2013 MTA Centre for Ecological Research

Impact Of Mid-Successional Dominant Species On The Diversity And Progress Of Succession In Regenerating Temperate Grasslands, Sandor Bartha, Szilard Szentes, Andras Horvath, Judit Hazi, Zita Zimmerman, Csaba Molnar, Istvan Dancza, Katalin Margoczi, Robert Pal, Dragica Purger, David Schmidt, Miklos Ovari, Cecelia Komoly, Zsuszanna Sutyinszki, Gabor Szabo, Andras Istvan Csatho, Melinda Juhasz, Karoly Penksza, Zsolt Molnar

Biological Sciences

(i) Which species dominate mid-successional old-fields in Hungary? How does the identity of these species relate to local (patch-scale) diversity and to the progress of succession? (ii) Which species have the strongest negative impact on diversity in spontaneous old-field succession and what generalizations are possible about traits of these species? (iii) Are these species dominant or subordinate components in mature target communities? (iv) Do native or alien species have stronger effects on the diversity and progress of succession?


Seed Burial Physical Environment Explains Departures From Regional Hydrothermal Model Of Giant Ragweed (Ambrosia Trifida) Seedling Emergence In U.S. Midwest, Adam S. Davis, Sharon Clay, John Cardina, Frank Forcella, John Lundquist, Christy Sprague 2013 USDA, Agricultural Research Service

Seed Burial Physical Environment Explains Departures From Regional Hydrothermal Model Of Giant Ragweed (Ambrosia Trifida) Seedling Emergence In U.S. Midwest, Adam S. Davis, Sharon Clay, John Cardina, Frank Forcella, John Lundquist, Christy Sprague

Agronomy, Horticulture and Plant Science Faculty Publications

Robust predictions of weed seedling emergence from the soil seedbank are needed to aid weed management. A common seed accession (Illinois) of giant ragweed was buried in replicate experimental gardens over 18 site years in Illinois, Michigan, Kansas, Nebraska, Ohio, and South Dakota to examine the importance of site and climate variability by year on seedling emergence. In a nonlinear mixed-effects modeling approach, we used a flexible sigmoidal function (Weibull) to model giant ragweed cumulative seedling emergence in relation to hydrothermal time accumulated in each site-year. An iterative search method across a range of base temperature (Tb ) and base and ...


Palmer Amaranth Confirmed In Western Iowa, Robert G. Hartzler, Richard O. Pope 2013 Iowa State University

Palmer Amaranth Confirmed In Western Iowa, Robert G. Hartzler, Richard O. Pope

Integrated Crop Management News

The presence of Palmer amaranth was recently confirmed in Harrison County near the Missouri River. The infestation was in two fields that have a history of land application of sludge. Because of the magnitude of the infestation, we believe the weed has been present for at least two growing seasons. We suspect the weed probably has spread to other fields in the area, but at this time we have not verified this.


Keep An Eye Out For ‘Odd’ Pigweeds, Robert G. Hartzler 2013 Iowa State University

Keep An Eye Out For ‘Odd’ Pigweeds, Robert G. Hartzler

Integrated Crop Management News

Most people are aware of the concerns regarding Palmer amaranth moving into Iowa. As discussed in an earlier article, distinguishing Palmer amaranth from waterhemp can be difficult in the vegetative stage. The majority of Amaranthusplants should currently be in the reproductive stage, greatly simplifying identification. Palmer amaranth produces long terminal branches on its inflorescences, capable of reaching lengths of three feet. The flowers of female Palmer amaranth plants have sharp bracts that are painful to the touch.


Distribution And Control Of Glyphosate-Resistant Johnsongrass (Sorghum Halepense) In Arkansas Soybean, Dennis Brent Johnson 2013 University of Arkansas, Fayetteville

Distribution And Control Of Glyphosate-Resistant Johnsongrass (Sorghum Halepense) In Arkansas Soybean, Dennis Brent Johnson

Graduate Theses and Dissertations

Johnsongrass, once the most persistent and troublesome grass weed of row crops throughout the southern U.S., has previously been confirmed resistant to the acetolactate synthase (ALS) and acetyl-coenzyme A carboxylase-inhibiting herbicides in the Midsouth and has recently evolved resistance to glyphosate in Arkansas. The goal of this research was to establish the geographical distribution of herbicide-resistant johnsongrass in Arkansas and to develop herbicide programs for controlling glyphosate-resistant johnsongrass in Arkansas soybean. Johnsongrass accessions were collected from 14 counties in the Mississippi River Delta region of Arkansas and screened for resistance to four of the most commonly used postemergence herbicides ...


2013 Weed Science Field Day Cancelled, Michael D. K. Owen 2013 Iowa State University

2013 Weed Science Field Day Cancelled, Michael D. K. Owen

Integrated Crop Management News

The Iowa State University Weed Science Field Day scheduled for June 27 has been cancelled.

As you are likely aware, the anticipated drought for 2013 has evaporated. Unfortunately, the rain that restored the water table has put planting in Iowa behind. There is still considerable acreage of corn and soybean that has yet to be planted across the state and Central Iowa likely represents the worst case. Records for the amount of rain in a spring and in May have been broken this year and the accumulation of growing degree days lags far behind the normal situation.


Is It Palmer Amaranth?, Robert G. Hartzler, Michael D. K. Owen 2013 Iowa State University

Is It Palmer Amaranth?, Robert G. Hartzler, Michael D. K. Owen

Integrated Crop Management News

Numerous weedy species in the pigweed family (Amaranthaceae) are found across Iowa, including waterhemp, redroot pigweed, smooth pigweed, Powell amaranth and others. At this time, Palmer amaranth has not been confirmed in the state, but because of its presence in surrounding states we suspect it may be here, or will appear in the near future.


Soil-Weed Seed Communication Systems, Jack H. Dekker 2013 Iowa State University

Soil-Weed Seed Communication Systems, Jack H. Dekker

Agronomy Publications

The nature of weeds is a complex adaptive, soil-seed communication system. The nature of weedy Setaria life history is an adaptable, changeable system in which complex behaviors emerge when self-similar plant components self-organize into functional traits possessing biological information about spatial structure and temporal behavior. Setaria life history behavior is a Markov chain of irreversible and reversible processes regulated by morpho-physiological traits acting through environment-plant communication systems (environment-plant-seed, soil-seed). Heritable functional traits are the physical reservoirs of information guiding life history development, emergent behavior. The consequence of structural self-similarity and behavioral self-organization has been the evolution of a complex adaptive ...


Distribution Of Burrowing Owls In East- Central South Dakota, Jiill A. Shaffer, Jason P. Thiele 2013 U.S. Geological Survey

Distribution Of Burrowing Owls In East- Central South Dakota, Jiill A. Shaffer, Jason P. Thiele

The Prairie Naturalist

Western burrowing owl (Athene cunicularia hypugaea) populations have declined across much of western North America, particularly at the northern and eastern edges of the species’ breeding range (Martell et al. 2001, Murphy et al. 2001, Shyry et al. 2001, Skeel et al. 2001, Klute et al. 2003). In South Dakota, the burrowing owl is a summer resident that historically was relatively common throughout the state, but its range has decreased in recent decades, especially in the eastern half of the state (Whitney et al. 1978, South Dakota Ornithologists’ Union [SDOU] 1991, Peterson 1995). Tallman et al. (2002) described the species ...


Notes: Nesting Patterns Of Red-Tailed Hawks And Great-Horned Owls In South-Cen- Tral Kansas, William Langley 2013 Butler Community College

Notes: Nesting Patterns Of Red-Tailed Hawks And Great-Horned Owls In South-Cen- Tral Kansas, William Langley

The Prairie Naturalist

Red-tailed hawks (Buteo jamaicensis) and great-horned owls (Bubo virginianus) can influence the nesting behavior of each other through direct competition for nesting sites. For instance, owls begin nesting before hawks and, thus, can use nests from the previous year and prevent hawks from occupying those sites (Orians and Kuhl- man 1956, Gilmer et al. 1983, Minor et al. 1993). However, both species sometimes kill the nestlings of the other (Craig- head and Craighead 1956, Bosakowski et al. 1989).

The objective of my study was to investigate nesting patterns of these two raptors at the edge of the tallgrass prairie over ...


Research Notes Vs. Research Articles, Christopher N. Jacques 2013 Western Illinois University

Research Notes Vs. Research Articles, Christopher N. Jacques

The Prairie Naturalist

Greetings GPNSS members! I hope this email finds you well, winding down another academic year, and looking forward to the summer field season. Warm temperatures, peak foliage, and heightened anticipation of the start of another field season are upon us following a long winter season and unusually wet spring for many of us across the Great Plains. Here in westcentral Illinois, wild turkeys are gobbling, neotropical migrants are singing and establishing breeding territories, and white-tailed deer are within days of giving birth to the next generation of fawns. Granted, there are many outdoor activities to participate in, though oppressive heat ...


Contributions Of Stocked And Naturally Reproduced Rainbow Trout In The Deerfield Reservoir System, Jacob L. Davis, Jerry W. Wilhite, Greg Simpson, Michael E. Barnes, Kaite N. Bertrand, David W. Willis 2013 South Dakota Department of Game, Fish and Parks

Contributions Of Stocked And Naturally Reproduced Rainbow Trout In The Deerfield Reservoir System, Jacob L. Davis, Jerry W. Wilhite, Greg Simpson, Michael E. Barnes, Kaite N. Bertrand, David W. Willis

The Prairie Naturalist

Deerfield Reservoir in the Black Hills of South Dakota and its tributary system are managed as hatchery supplemented rainbow trout (Oncorhynchus mykiss) fisheries. Three genetically unique strains of rainbow trout (Shasta, Erwin and McConaughy) are stocked into the system. Recently, juvenile rainbow trout of unknown origin were collected in the tributary system above Deerfield Reservoir, indicating potential natural reproduction. Understanding the genetic origins and ability of these rainbow trout to contribute to the fishery is essential in determining the proper management strategy for these waters. Our objectives were to 1) evaluate the genetic origins of potentially naturally reproduced rainbow trout ...


Genetic Diversity Of Seed Dormancy And Molecular Evolution Of Weedy Red Rice, Te Ming Tseng 2013 University of Arkansas, Fayetteville

Genetic Diversity Of Seed Dormancy And Molecular Evolution Of Weedy Red Rice, Te Ming Tseng

Graduate Theses and Dissertations

Rice is the grain with the third-highest global production. In the US, Arkansas is the largest rice producing state; however, an estimated 62% of the rice fields in the state are infested with red rice, and can cause up to 80% yield reduction in rice. Among its weedy traits, seed dormancy plays an important role in its persistence, and helps red rice escape weed management techniques thereby increasing the red rice soil seedbank. Red rice also has the potential to hybridize among themselves and with cultivated rice, thus resulting in diverse phenotypes and genotypes. In this study we measured variation ...


Glyphosate-Resistant Palmer Amaranth (Amaranthus Palmeri) In Arkansas: Resistance Mechanisms And Management Strategies, Griff Michael Griffith 2013 University of Arkansas, Fayetteville

Glyphosate-Resistant Palmer Amaranth (Amaranthus Palmeri) In Arkansas: Resistance Mechanisms And Management Strategies, Griff Michael Griffith

Graduate Theses and Dissertations

Since 2000, there have been thirteen weed species confirmed resistant (R) to glyphosate in the United States, six of those resistant species are present in Arkansas. The goal of this research was to confirm and to determine the level of resistance in two R Palmer amaranth biotypes from Mississippi (MC-R) and Lincoln (LC-R) Counties, Arkansas, and one susceptible (S) biotype from Clarendon County, South Carolina, which had never been exposed to glyphosate. Shikimic acid concentration over time was significantly greater in the S biotype than both the MC-R and LC-R biotypes. The lethal dose required to kill 50% (LD50 ...


Don’T Delay The Burndown Application, Robert G. Hartzler 2013 Iowa State University

Don’T Delay The Burndown Application, Robert G. Hartzler

Integrated Crop Management News

The late arrival of spring has everyone ready to hit the fields running when fields finally dry out. Some will be tempted to forgo applying herbicides prior to planting to ensure fields get planted in case another wet period arrives. This is an exceptionally risky proposition for no-till fields because it provides weeds a head start on the crop and a competitive advantage for the rest of the season. If everything falls in place perfectly, this practice can be successful. But any delay in getting back into the field to apply the burndown and residual herbicides can have a big ...


Troublesome Palmer Amaranth Expanding Its Range, Robert G. Hartzler, Michael D. K. Owen 2013 Iowa State University

Troublesome Palmer Amaranth Expanding Its Range, Robert G. Hartzler, Michael D. K. Owen

Integrated Crop Management News

Many people are aware of the problems Palmer amaranth is causing farmers in the mid-south and southeast United States. Palmer amaranth is a close relative to Iowa’s number one weed problem – waterhemp. Like waterhemp, Palmer amaranth is a species with a propensity to evolve herbicide resistance. Glyphosate resistant Palmer amaranth devastated the cotton industry, which has fewer chemical options than available in corn and soybean. This article will describe Palmer amaranth and the risk of it appearing in Iowa.


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