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Soil Health And Productivity In Riparian Grass Buffers: A Re-Evaluation After 13 Years, James W. Raich, Richard Schulz Jan 2015

Soil Health And Productivity In Riparian Grass Buffers: A Re-Evaluation After 13 Years, James W. Raich, Richard Schulz

Leopold Center Completed Grant Reports

In 2001, soil health and productivity were surveyed in riparian grassland buffers adjacent to Bear Creek in northern Story County, Iowa. The investigators resampled these 24 plots in 2014 using the same techniques to see what changes had resulted from the conservation practices applied in the intervening years.


Conclusive Evidence Of Replication Of A Plant Virus In Honeybees Is Lacking, W. Allen Miller, Jimena Carrillo-Tripp, Bryony C. Bonning, Adam G. Dolezal, Amy L. Toth May 2014

Conclusive Evidence Of Replication Of A Plant Virus In Honeybees Is Lacking, W. Allen Miller, Jimena Carrillo-Tripp, Bryony C. Bonning, Adam G. Dolezal, Amy L. Toth

Entomology Publications

The recent article by Li et al. (1) lacks adequate evidence to support the authors’ assertion that a plant virus propagates or replicates in honeybees. Instead, it is possible that tobacco ringspot virus (TRSV) virions associate with the honeybee and parasitic Varroa mites in the absence of TRSV replication.


Reassessment Of Practical Subspecies Identifications Of The Usda Daucus Carota L. Germplasm Collection: Morphological Data, David M. Spooner, Mark P. Widrlechner, Kathleen R. Reitsma, Debra E. Palmquist, Slim Rouz, Zeineb Ghrabi-Gammar, Mohamed Neffati, Béchir Bouzbida, Philipp W. Simon, Mohammed El Koudrim Feb 2014

Reassessment Of Practical Subspecies Identifications Of The Usda Daucus Carota L. Germplasm Collection: Morphological Data, David M. Spooner, Mark P. Widrlechner, Kathleen R. Reitsma, Debra E. Palmquist, Slim Rouz, Zeineb Ghrabi-Gammar, Mohamed Neffati, Béchir Bouzbida, Philipp W. Simon, Mohammed El Koudrim

NCRPIS Publications and Papers

The genus Daucus includes about 20 recognized species. The most widespread and economically important species, Daucus carota L., occurs on almost every continent. The cultivated carrot, subsp. sativus (Hoffm.) Schübl. and G. Martens, has been selected from wild populations that are extremely diverse, especially in the western Mediterranean. The predominant outcrossing and the lack of sexual isolating mechanisms among recognized infraspecific taxa complicate the taxonomy and identification of the wild populations, resulting in widely different interpretations of the number of infraspecific taxa. We measured 36 morphological characters from multiple individuals within each of 155 accessions of D. carota and from ...


Transitioning To Ecologically Functional Production Systems, Kirsten S. Hofmockel, Lisa A. Schulte Moore, Thomas M. Isenhart, Randall K. Kolka Jan 2014

Transitioning To Ecologically Functional Production Systems, Kirsten S. Hofmockel, Lisa A. Schulte Moore, Thomas M. Isenhart, Randall K. Kolka

Leopold Center Completed Grant Reports

A gap in transitioning to ecologically beneficial farming practices is the lack of understanding of how soils store carbon (C) and nitrogen (N)long term. Farmers need management practices for improving soil quality, increasing both belowground (live roots) and aboveground (live cover) biomass, increasing soil organic matter, and reducing greenhouse gas emissions. This project quantified root productivity, root decomposition, soil microbial dynamics, soil aggregation, and belowground C allocation in annual and perennial biomass cropping systems across multiple landscape positions.


Biochar And Managed Perennial Ecosystems: Testing For Synergy In Ecosystem Function And Biodiversity, Lori A. Biederman, W. Stanley Harpole Jan 2014

Biochar And Managed Perennial Ecosystems: Testing For Synergy In Ecosystem Function And Biodiversity, Lori A. Biederman, W. Stanley Harpole

Iowa State Research Farm Progress Reports

Biochar is a carbon-rich material that is similar to charcoal. It is produced when biomass is burned in the absence of oxygen, a process otherwise known as pyrolysis. Pyrolysis and the production of biochar are currently being promoted as a means to both produce domestic fuel (bio-oil) while concurrently producing a co-product that increases crop yield and sequesters carbon in the soil (biochar). Although there may be many potential benefits in the application of biochar to agricultural soils, such as enhanced soil fertility and improved soil water status, there are no studies of higher-order ecological and ecosystem effects of biochar ...


Adding A Second Native Prairie Seed Addition To Improve Established Restorations, Leanne M. Martin, Brian J. Wilsey Jan 2013

Adding A Second Native Prairie Seed Addition To Improve Established Restorations, Leanne M. Martin, Brian J. Wilsey

Iowa State Research Farm Progress Reports

Deciding when and how to plant prairie to simultaneously establish native prairie seedlings and prevent weed (non-prairie species) invasion can be challenging. Planting cover crops is an increasingly common management practice for prairie plantings. The idea is based on the assumption that the cover plant will act as a nurse plant to prairie seedlings and will have a positive effect on seedling recruitment by increasing weed suppression. This is predicted to lead to reduced weed biomass and increased prairie establishment in restoration plantings.


Oakridge Research And Education Prairie, Brent D. Mortensen, Lauren K. Sullivan, W. Stanley Harpole Jan 2013

Oakridge Research And Education Prairie, Brent D. Mortensen, Lauren K. Sullivan, W. Stanley Harpole

Iowa State Research Farm Progress Reports

Reconstructed tallgrass prairies (prairies that have been replanted) in Iowa and elsewhere in the Great Plains often lose many of the planted species over time, leading to lower diversity compared with prairie remnants. Establishment and maintenance of diversity in these reconstructions may be heavily influenced by herbivores. Herbivores such as white-tailed deer (Odocoileus virginianus), rabbits, and voles (Microtus spp.) may increase prairie diversity by eating competitively dominant plants, or decrease diversity by eating rare species. In addition to consuming adult plants, herbivores may further affect plant diversity by consuming seeds and seedlings and/or dispersing seeds to new locations.


Effects Of Overwintering Conditions On Nesting Behavior Of Painted Turtles, Timothy Mitchell, Cecilia Hinsley, Fredric J. Janzen Ii Jan 2013

Effects Of Overwintering Conditions On Nesting Behavior Of Painted Turtles, Timothy Mitchell, Cecilia Hinsley, Fredric J. Janzen Ii

Iowa State Research Farm Progress Reports

For painted turtles (Chrysemys picta) and many other reptiles, the temperature experienced by developing eggs determines whether the embryo will become a male or a female. Animals with this temperaturedependent sex determination (TSD) are vulnerable to rapid climate change, as consistent, directional changes in climate may result in detrimental population sex-ratio shifts. Yet, many animals with TSD have persisted for millions of years, through many periods of global warming and cooling. How have these animals evolved to maintain healthy sex ratios, despite this apparent vulnerability?


Biochar And Managed Perennial Ecosystems: Testing For Synergy In Ecosystem Function And Biodiversity, Lori A. Biederman, W. Stanley Harpole Jan 2013

Biochar And Managed Perennial Ecosystems: Testing For Synergy In Ecosystem Function And Biodiversity, Lori A. Biederman, W. Stanley Harpole

Iowa State Research Farm Progress Reports

Biochar is a carbon-rich material that is similar to charcoal. It is produced when biomass is burned in the absence of oxygen, a process otherwise known as pyrolysis. Pyrolysis and the production of biochar are currently being promoted as a means to both produce domestic fuel (biooil) and concurrently producing a co-product that increases crop yield and sequesters carbon in the soil (biochar). While there may be many potential benefits in the application of biochar to agricultural soils, such as enhanced soil fertility and improved soil water status, there are no studies of higher-order ecological and ecosystem effects of biochar ...


Variation In Seed Dormancy In Echinochloa And The Development Of A Standard Protocol For Germination Testing. Ii: Breaking Dormancy In Seeds Unresponsive To Light Or Dark Conditions Alone By Using Heat And Ethanol Pretreatment, David A. Kovach, Mark P. Widrlechner, David M. Brenner Oct 2012

Variation In Seed Dormancy In Echinochloa And The Development Of A Standard Protocol For Germination Testing. Ii: Breaking Dormancy In Seeds Unresponsive To Light Or Dark Conditions Alone By Using Heat And Ethanol Pretreatment, David A. Kovach, Mark P. Widrlechner, David M. Brenner

NCRPIS Publications and Papers

A recently established method for the germination of Echinochloa seeds recognised and accounted for variation in responses to light and darkness. This method used parallel light and dark tests and was successful in promoting germination in most seed lots. However, some samples exhibited deeper dormancy and were not fully responsive to either test. In the present study, we employed warm pretreatments where seeds were exposed to dilute aqueous ethanol solutions to attempt to break their dormancy. Based on tests of five Echinochloa accessions, we propose a new, follow-up protocol that can be used on samples unresponsive to the established method ...


Improving Prairie Restorations, Leanne M. Martin, Brian J. Wilsey Jan 2012

Improving Prairie Restorations, Leanne M. Martin, Brian J. Wilsey

Iowa State Research Farm Progress Reports

Deciding when and how to plant prairie to simultaneously establish native prairie seedlings and prevent weed (non-prairie species) invasion can be challenging. Planting cover crops is an increasingly common management practice for prairie plantings. The idea is based on the assumption that the cover plant will act as a nurse plant to prairie seedlings and will have a positive effect on seedling recruitment by increasing weed suppression. This is predicted to lead to reduced weed biomass and increased prairie establishment in restoration plantings.


Species Diversity Is A Good Predictor Of Prairie Plant Persistence In Restorations, Brian J. Wilsey, Yue Huang, Leanne M. Martin Jan 2012

Species Diversity Is A Good Predictor Of Prairie Plant Persistence In Restorations, Brian J. Wilsey, Yue Huang, Leanne M. Martin

Iowa State Research Farm Progress Reports

Prairie restoration projects sometimes fail because of heavy invasion by invasive weeds, especially if they are not intensively managed. Few restoration projects are sampled after the first few years post-establishment, and little is known about what predictors are significant in maintaining restored communities over the very long term. Here, we stopped weeding experimental restoration plots to determine if persistence (that is, remaining unchanged after weeds are allowed to invade) of native prairie in western Iowa was related to planted species diversity


Native Cover Crops And Timing Of Planting: Three Years Of Establishment, Leanne M. Martin, Brian J. Wilsey Jan 2011

Native Cover Crops And Timing Of Planting: Three Years Of Establishment, Leanne M. Martin, Brian J. Wilsey

Iowa State Research Farm Progress Reports

Deciding when and how to plant prairie to simultaneously establish native prairie seedlings and prevent weed (non-prairie species) invasion can be challenging. Planting cover crops is an increasingly common management practice for prairie plantings. The idea is based on the assumption that the cover plant will act as a nurse plant to prairie seedlings and will have a positive effect on seedling recruitment by increasing weed suppression. This is predicted to lead to reduced weed biomass and increased prairie establishment in restoration plantings. However, the evidence supporting these benefits is mostly anecdotal and has been challenged by some.


The Effects Of Egg-Incubation Temperature On Growth And Survival Of Hatchling Painted Turtles, Daniel Warner, Timothy Mitchell, Fredric J. Janzen Ii Jan 2011

The Effects Of Egg-Incubation Temperature On Growth And Survival Of Hatchling Painted Turtles, Daniel Warner, Timothy Mitchell, Fredric J. Janzen Ii

Iowa State Research Farm Progress Reports

The environmental conditions that reptile embryos experience during development have profound effects on many offspring traits. For example, incubation temperature affects offspring body size, growth rate, running performance, and even gender—all phenotypic traits that are important for survival and reproduction (i.e., fitness). Although these effects on fitness-related traits are well known, very few studies have evaluated the long-term consequences of incubation temperature on survival and reproduction, particularly in long-lived species.


Increasing Native Plant Species Richness Can Increase Ecosystem Multifunctionality Under Intense Livestock Grazing, Forest I. Isbell, Brian J. Wilsey Jan 2010

Increasing Native Plant Species Richness Can Increase Ecosystem Multifunctionality Under Intense Livestock Grazing, Forest I. Isbell, Brian J. Wilsey

Iowa State Research Farm Progress Reports

Species rich native grasslands are frequently converted to species poor exotic pastures; however, the consequences of these land use changes for ecosystem functioning remain unclear. Specifically, it is unclear whether: 1) intense livestock grazing will have similar effects in native and exotic ecosystems, and 2) pasture productivity can be increased by increasing species richness, by changing from native to exotic species, or simply by identifying the most productive species.


Native Cover Crops And Timing Of Planting: Effects On 15n Uptake, Weed Invasion And Prairie Establishment, Brian J. Wilsey Jan 2009

Native Cover Crops And Timing Of Planting: Effects On 15n Uptake, Weed Invasion And Prairie Establishment, Brian J. Wilsey

Leopold Center Completed Grant Reports

Cover crops have been used for several purposes in prairie restorations. This project looked at whether the assumed benefits are supported by research results.


The Effect Of Plant Distribution On Diversity And Exotic Species Invasion In Prairie Restoration, Kathryn Anne Yurkonis, Brian J. Wilsey, Kirk A. Moloney Jan 2009

The Effect Of Plant Distribution On Diversity And Exotic Species Invasion In Prairie Restoration, Kathryn Anne Yurkonis, Brian J. Wilsey, Kirk A. Moloney

Iowa State Research Farm Progress Reports

The most abundant plants in restored prairies are often distributed in large, single-species stands despite our efforts to establish high diversity plantings. This likely occurs as weaker species are excluded by stronger competitors during the first few years of establishment. The resulting distribution of plants into large patches in space may promote establishment of non-planted species in restored prairies, further compromising restoration success.


Exotic Species And Overgrazing Can Drive Declines In Grassland Biodiversity And Productivity, Forest I. Isbell, Brian J. Wilsey Jan 2009

Exotic Species And Overgrazing Can Drive Declines In Grassland Biodiversity And Productivity, Forest I. Isbell, Brian J. Wilsey

Iowa State Research Farm Progress Reports

Plant species diversity has declined rapidly in grasslands, and it is poorly known how to establish and maintain diverse mixtures containing grasses, forbs, and legumes. Each of these groups can be important. For example, grasses and forbs can produce forage and increase resistance to weeds, and legumes can produce forage and maintain high fertility by fixing nitrogen. There is some evidence that exotic (introduced) plant species and changes in land use are contributing to declines in diversity. Exotic species could be causing declines in diversity in situations where they differ from native plant species in growth rates and other plant ...


Effects Of High Intensity Grazing And Exotic Plant Species On Grassland Biodiversity And Productivity, Forest I. Isbell, Brian J. Wilsey Jan 2008

Effects Of High Intensity Grazing And Exotic Plant Species On Grassland Biodiversity And Productivity, Forest I. Isbell, Brian J. Wilsey

Iowa State Research Farm Progress Reports

Plant species diversity has declined rapidly in grasslands, and it is poorly known how to establish and maintain diverse mixtures containing grasses, forbs, and legumes. Each of these groups can be important in at least some situations, with grasses and forbs producing forage and increasing resistance to weeds, and legumes producing forage and maintaining high fertility by fixing nitrogen. There is some evidence that exotic (introduced) plant species and changes in land use are contributing to declines in diversity. Exotic species could be causing declines in diversity in situations where they differ from native plant species in growth rates and ...


Native Cover Crops And Timing Of Planting: Effects On Weed Invasion And Prairie Establishment, Brian J. Wilsey, Andrea Blong Jan 2008

Native Cover Crops And Timing Of Planting: Effects On Weed Invasion And Prairie Establishment, Brian J. Wilsey, Andrea Blong

Iowa State Research Farm Progress Reports

Planting cover crops to simultaneously establish native prairie seedlings and prevent weed invasion is an increasingly common management practice for prairie plantings. The idea is based on the assumption that the cover plant will act as a nurse plant to prairie seedlings, and will have a positive effect on seedling recruitment by increasing weed suppression and by lowering the harmful effects of high evaporation and light availabilities. Cover crops could also potentially reduce the amount of soil erosion that occurs during planting. This is predicted to lead to reduced weed biomass and increased prairie establishment in restoration plantings.


Native Cover Crops: Effects On Weed Invasion And Prairie Establishment, Brian J. Wilsey, Andrea Blong Jan 2007

Native Cover Crops: Effects On Weed Invasion And Prairie Establishment, Brian J. Wilsey, Andrea Blong

Iowa State Research Farm Progress Reports

There are several native species that have potential as cover crops. During the 2004 growing season, we established five native species as cover crops at two separate sites, the Horticulture Research Station and the Western Research Farm, and we have been measuring cover crop and prairie species establishment, biomass production, and weed suppression annually since then. The objective of our study was to develop a better understanding of how cover plants are affecting weed and prairie species establishment.


Native Cover Crops: Effects On Weed Invasion And Prairie Establishment, Brian J. Wilsey, Andrea Blong Jan 2007

Native Cover Crops: Effects On Weed Invasion And Prairie Establishment, Brian J. Wilsey, Andrea Blong

Iowa State Research Farm Progress Reports

There are several native species that have potential as cover crops. During the 2004 growing season, we established five native species as cover crops at two separate sites, the Horticulture Research Station and the Western Research Farm, and we have been measuring cover crop and prairie species establishment, biomass production, and weed suppression annually since then. The objective of our study was to develop a better understanding of how cover plants are affecting weed and prairie species establishment.


Biomass Production Varies Among Native Prairie-Grass Species, Brian J. Wilsey Jan 2007

Biomass Production Varies Among Native Prairie-Grass Species, Brian J. Wilsey

Iowa State Research Farm Progress Reports

Native grasslands provide a multitude of benefits to society including forage production, wildlife habitat, and nutrient and CO2 sequestration. There has been increasing interest in using native perennial grassland plantings to produce cellulose-based biofuels. However, there is little information on how biomass production might vary among different native species in a comparable field setting in Western Iowa. Perennial warm-season grasses such as big bluestem, Indian grass, switchgrass, little bluestem or side-oats grama often dominate prairies. In Western Iowa, all five of these species dominate in at least some grassland plantings. In an ongoing study, we are studying how different warm-season ...


Evolutionary Ecology Of Freshwater Turtles, Nicole M. Valenzuela Jan 2007

Evolutionary Ecology Of Freshwater Turtles, Nicole M. Valenzuela

Iowa State Research Farm Progress Reports

This long-term study explores the evolution of life history traits(e.g. reproductive traits such as mating system, migratory behavior,sex determination, demography) and the footprint that those traits leave on the genetic makeup of populations(e.g. genetic differentiation, gene flow) to understand the ecological and evolutionary significance of trait variation, and to provide information important for the conservation of reptiles, particularly turtles. The project consists of several phases that investigate complementary ecological and evolutionary modules related to this main goal. Those modules are: population genetics, paternity analyses, gene expression during sex differentiation, and molecular evolution of genes and ...


Reconstructing Quaternary Landscapes And Hydrology From Soil Survey Maps, Bradley A. Miller Jan 2006

Reconstructing Quaternary Landscapes And Hydrology From Soil Survey Maps, Bradley A. Miller

Retrospective Theses and Dissertations

This study was done to investigate the pre-settlement condition of the southern Des Moines Lobe landscape, with particular interest in the hydrological function of depressional wetlands. Soil survey maps were used to identify the soil formation environment from soil properties observed today. Understanding the factors of soil formation and geomorphology allows historical reconstructions of the landscape, hydrology, wildlife habitat, and potentially other areas of interest. This study interpreted and managed soil survey data to efficiently create a Quaternary geologic map, identify the extents of historical depressional wetlands, deduce information about the water budget of these wetlands, and estimate the region ...


Biomass Production And Soil Respiration In Experimental Riparian Grass Filter Strips, James W. Raich, Germán Mora Jan 2006

Biomass Production And Soil Respiration In Experimental Riparian Grass Filter Strips, James W. Raich, Germán Mora

Iowa State Research Farm Progress Reports

Grass filter strips established between cropped fields and streams have many potential conservation benefits, including trapping sediments and runoff, providing wildlife habitat, transforming nitrogen in runoff waters, sequestering soil carbon, and enhancing soil tilth. In this study, we compared five species of grasses with respect to above ground biomass production and soil respiration (i.e., CO2 flux), the latter being a robust measure of total soil biological activity. The information may help landowners select the best grass species for planting in streamside filters and buffer strips.


Plant Species Effects On Diversity And Weed Invasion Resistance In Restored Grasslands, Brian J. Wilsey, David Losure Jan 2006

Plant Species Effects On Diversity And Weed Invasion Resistance In Restored Grasslands, Brian J. Wilsey, David Losure

Iowa State Research Farm Progress Reports

Native grasslands provide a multitude of benefits to society including forage production, wildlife habitat, and nutrient and CO2 sequestration. There has been continuing interest in restoring grasslands to maximize these multiple benefits within the conservation community. There are presently many ongoing prairie restoration projects, and many more are being started throughout Iowa. Warm-season grasses such as big bluestem, indian grass, switchgrass, little bluestem, or side-oats grama often dominate prairies. In western Iowa, all five of these species are dominant, at least in some patches of grassland. Diversity is what most people are most concerned with when they restore or reconstruct ...


Native Cover Crops: Effects On Weed Invasion And Prairie Establishment, Brian J. Wilsey, Andrea Blong Jan 2006

Native Cover Crops: Effects On Weed Invasion And Prairie Establishment, Brian J. Wilsey, Andrea Blong

Iowa State Research Farm Progress Reports

Planting cover crops to simultaneously establish native prairie seedlings and prevent weed invasion is an increasingly common management practice. The idea is based on the assumptions that the cover plant will act as a nurse plant to prairie seedlings and that it will have a positive effect on seedling recruitment by suppressing weeds and by lowering the harmful effects of high evaporation and light availability. Cover crops could also potentially reduce the amount of soil erosion that occurs during planting. However, the evidence supporting the benefits of cover crops is mostly anecdotal and has been challenged. Clearly, there is a ...


Native Cover Crops: Germination And First-Season Cover And Biomass, Brian J. Wilsey, Andrea Blong Jan 2005

Native Cover Crops: Germination And First-Season Cover And Biomass, Brian J. Wilsey, Andrea Blong

Iowa State Research Farm Progress Reports

Planting cover crops to simultaneously establish native prairie seedlings and prevent weed invasion is a common management practice. The idea is based on the assumptions that the cover plant will act as a nurse plant to the prairie seedlings and that it will have a positive effect on seedling recruitment by increasing weed suppression and by lowering the harmful effects of high evaporation and light availabilities. Furthermore, plowed ground is ideal habitat for a host of weedy species that have higher germination and early growth rates, especially above ground, than do prairie species. Cover crops could also potentially reduce the ...


Prairie Cover Crops: Germination And First-Season Cover And Biomass, Brian J. Wilsey, Andrea Blong Jan 2005

Prairie Cover Crops: Germination And First-Season Cover And Biomass, Brian J. Wilsey, Andrea Blong

Iowa State Research Farm Progress Reports

No abstract provided.