Life Sciences Commons^™

Winter Cover Crop Impacts On Weed Dynamics In Eastern And Central Nebraska, Elizabeth Ann Oys

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

Reducing tillage in cropping systems causes weed management to be dependent on chemical and cultural methods for weed control. Over time, herbicide-resistant weeds have developed due to the continuous selection pressures from herbicides, particularly in the Midwest Corn Belt. Integrated weed management strategies, such as cover crops, can be used to mitigate some of these issues. Cover crops are primarily known for their soil health benefits, but there is evidence that cover crops can suppress weeds. However, less research has been done at the field-scale level to address cover crop impacts on the weed seedbank and aboveground weeds during the …

Water Use Characteristics Of Weeds: A Global Review, Best Practices, And Future Directions, Mandeep Singh, Meetpal Singh Kukal, Suat Irmak, Amit J. Jhala

Department of Agronomy and Horticulture: Faculty Publications

Weeds usually penalize crop yields by competing for resources, such as water, light, nutrients, and space. Most of the studies on the crop-weed competition domain are limited to assessing crop-yield losses due to weed pressure and other crop-weed interactions, overlooking the significant uptake of soil-water by weeds that exacerbates global water constraints and threatens the productivity and profitability. The objective of this review was to synthesize globally available quantitative data on weed water use (WU) sourced from 23 peer-reviewed publications (filtered from 233 publications via a multi-step protocol of inclusion criteria) with experimental investigations across space (3 continents), time (1927–2018), …

Nitrogen And Weed Management In Transplanted Tomato In The Nigerian Forest-Savanna Transition Zone, J. A. Adigun, O. S. Daramola, O. R. Adeyemi, P. M. Olorunmaiye, O. A. Osipitan

Haskell Agricultural Laboratory (Northeast Research and Extension Center)

Weed infestation and inherent low soil fertility are among primary reasons for low yields of tomato in Nigeria. Field trials were carried out during the wet season of 2015 and 2016 to evaluate yield response of tomato to nitrogen (N) application and weed control methods in the forest-savanna transition zone of Abeokuta, Nigeria. Positive relationship exists between growth of weed species and increase in N application. Across the years of study, increase in N up to 90 kg/ha increased weed density by 11–25%, however, the increased N gave the transplanted tomato competitive advantage and thus enhanced weed smothering. Pre-transplant application …

Abundance Of And Floral Herbivory On Exotic Bull Thistle Versus Native Tall Thistle In Western Tallgrass Prairie, Chad P. Andersen, Svata M. Louda

School of Biological Sciences: Faculty Publications

An important, yet poorly quantified mechanism to explain the failure of some exotic species to increase and spread is that indigenous natural enemies provide ecosystem resistance to invasiveness. To evaluate this idea, we hypothesized that spillover of native thistle-feeding floral insect herbivores onto Eurasian bull thistle (Cirsium vulgare) from the prairie native tall thistle (C. altissimum) helps limit bull thistle population growth and spread throughout the western tallgrass prairie region in Nebraska. To test this hypothesis, we quantified both the occurrence of bull thistle, a known invasive species worldwide, and the floral herbivory on it by …

Host Specificity Of Divergent Populations Of The Leaf Beetle Diorhabda Elongata (Coleoptera: Chrysomelidae), A Biological Control Agent Of Saltcedar (Tamarix Spp.), Lindsey R. Milbrath, C. Clark Deloach

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The leaf beetle, Diorhabda elongata (Brullé) sensu lato, was released in 2001 for the classical biological control of exotic saltcedars, a complex of invasive Tamarix species and hybrids. It did not establish at sites south of 37°N latitude where summer daylengths are below the critical photoperiod of the northern-adapted populations of the beetle that were released. Therefore, we assessed the host specificity of four D. elongata populations collected from more southern latitudes in the Old World (Tunisia, Crete, Uzbekistan, and Turpan, China). All populations were similar to each other and the previously released populations of D. elongata in their …

Survey Of Phytophagous Insects And Foliar Pathogens In China For A Biocontrol Perspective On Kudzu, Pueraria Montana Var. Lobata (Willd.) Maesen And S. Almeida (Fabaceae), Jiang-Hua Sun, Zhu-Dong Liu, Kerry O. Britton, Ping Cai, David Orr, Judith Hough-Goldstein

USDA Forest Service / UNL Faculty Publications

A three-year survey of kudzu foliage, seed, stems, and roots for associated phytophagous insects was conducted to establish basic information about the insect communities that kudzu harbors in China and to assess the abundance, diversity and damage caused by these insects. Diseases of kudzu were also surveyed in southern China. A total of 116 phytophagous insect species in 31 families and 5 orders were collected from kudzu in China, in six feeding guilds: foliage, sap, stem, terminal, seed and root feeders. The impact of foliage feeders varied from site to site and year to year, and over the course of …

Host Specificity Of The Leaf Beetle, Diorhabda Elongata Deserticola (Coleoptera: Chrysomelidae) From Asia, A Biological Control Agent For Saltcedars (Tamarix: Tamaricaceae) In The Western United States, C. Jack Deloach, Phil A. Lewis, John C. Herr, Raymond I. Carruthers, James L. Tracy, Joye Johnson

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Four species of saltcedars, Tamarix ramosissima Ledeb., Tamarix chinensis Lour., Tamarix parviflora DC., and T. canariensis Willd. and their hybrids, are exotic, invasive small trees from Asia that cause great damage to riparian ecosystems of the western United States. They displace native plant communities, degrade wildlife habitat (including that of many endangered species), increase soil salinity and wildfires, lower water tables, reduce water available for agriculture and municipalities, and reduce recreational use of affected areas. Phytophagous insects are abundant on saltcedar in the Old World and we selected Diorhabda elongata Brullé deserticola Chen as the top candidate biological control agent …

Ec03-176 Noxious Weeds Of Nebraska: Musk Thistle, Fred Roeth, Steven R. Melvin, Irvin L. Schleufer

University of Nebraska-Lincoln Extension: Historical Materials

Musk Thistle is an introduced invasive broadleaf weed native to Europe, North Africa, and Asia. In these areas it is a minor weed because natural enemies keep its population low. When the plant was introduced into North America, its natural enemies were left behind. Without these natural checks, the thistle is able to thrive and compete with native vegetation. This Extension Circular discusses the history, biology, identification, distribution and control of the musk thistle.

Ec03-181 Alfalfa In Nebraska, Bruce Anderson, Loren J. Giesler, Thomas E. Hunt, Shripat T. Kamble, Stevan Z. Knezevic, Charles A. Shapiro

University of Nebraska-Lincoln Extension: Historical Materials

Alfalfa is the most important forage crop grown in Nebraska, with over 1,000 acres grown in every county. It has the highest feeding value for livestock and one of the highest yield potentials. Alfalfa can produce more protein per acre than any other crop and can provide all of the protein needed by many livestock as well as supplying large amounts of vitamins, minerals, and energy. Protein of alfalfa. In also covers the cultural practices, insect pests, diseases, weeds that affect alfalfa.

Bindweed Identification And Control Options For Organic Production, Laurie Hodges

University of Nebraska-Lincoln Extension: Historical Materials

Two species of bindweed are commonly found in the Great Plains and one unrelated weed is often confused with bindweed.

Ec02-174 Noxious Weeds Of Nebraska: Leafy Spurge, Robert A. Masters, Brady Kappler

University of Nebraska-Lincoln Extension: Historical Materials

Leafy spurge is an invasive weed that infests over three million acres in the northern Great Plains and the prairie provinces of Canada. It is commonly found in rangelands, pastures, roadsides, rights-of-way, and woodlands. Leafy spurge can reduce rangeland and pasture carrying capacity by as much as 75 percent because it competes with forages and cattle avoid grazing areas infested with this weed.

This Extension Circular discusses the biology, identification, distribution and control of leafy spurge.

Rearing And Releasing Galerucella Beetles To Control Purple Loosestrife, Stevan Z. Kenzevic, Doug Smith

University of Nebraska-Lincoln Extension: Historical Materials

Purple loosestrife is a noxious weed quickly invading Nebraska's wetlands. This publication describes the rearing and releasing of insects for biological control of the weed, as one part of an integrated management program. Purple loosestrife is a noxious perennial weed invading thousands of acres of wetlands and waterways in the Midwest. In Nebraska an estimated 18,000 acres are already infested by this plant, mostly along the main rivers and waterways. It has no natural enemies in North America, therefore it is very hard to prevent it from spreading. For years people have tried to eradicate it, especially in the Great …

Herbicide Resistant Weeds, Alex R. Martin, Fred W. Roeth, Chad Lee

University of Nebraska-Lincoln Extension: Historical Materials

The development of herbicide resistant weeds is described along with strategies to prevent development. Herbicide resistance refers to plants within a weed species that, after repeated use of a herbicide, are no longer controlled by normal rates of that herbicide. Herbicide resistance often develops in fields that have been sprayed with herbicides with the same site of action for several years. Herbicide resistance is usually attributed to slight genetic differences between resistant and susceptible plants. These changes occur at a frequency of one plant in a million or even a billion. Herbicide resistance is not dependent on the environment or …

Nf98-372 Preparation And Use Of Wheatgrass Stands After Crp And Associated Costs/Income — Part I, Patrick E. Reece, Tom Holman, David W. Cook

University of Nebraska-Lincoln Extension: Historical Materials

Wheatgrass species (Agropyron spp.) were seeded on many Conservation Reserve Program (CRP) acres in western Nebraska and adjoining states. These species included crested (A. cristatum, desertorum), intermediate (A. intermedium), pubescent (A. trichophorum) and western (A. smithii) wheatgrasses. Good to excellent stands of wheatgrass can be valuable forages sources for livestock during the spring, summer, or fall, however, accumulation of large amounts of poor quality residual herbage during 10-year CRP contract periods can reduce animal performance.

This NebGuide discusses field evaluations, results, recommended preparations, spring and summer grazing after CRP; and associated …

G98-1343 Fall Vegetable Gardening, Dale T. Lindgren, Susan D. Schoneweis

University of Nebraska-Lincoln Extension: Historical Materials

This NebGuide discusses the possibilities for and needs of a fall garden.

Though often overlooked by the gardener, planting vegetables in July and August for fall production is an excellent practice. Late plantings of cool- and warm-season vegetables can extend the harvest long after spring-planted crops have ceased production. Most cool-season vegetables grow as well as or better than those planted in the spring as they mature during shorter, cooler days. Flavors of vegetables maturing in the cool, crisp days of autumn are often sweeter and milder than those grown during hot summer weather. This is especially true for cole …

Nf98-363 Chemical Weed Control In Tree Planting Projects: Part Ii - Post-Emergence Herbicides, John Duplissis

University of Nebraska-Lincoln Extension: Historical Materials

This NebFact examines weed control in tree planting projects.

Ec98-151 Amaranth: Production Manual For The Central United States, Jane Sooby, David D. Baltensperger, Robert Myers, David Brenner, Richard Wilson, Charles Block

University of Nebraska-Lincoln Extension: Historical Materials

Amaranth is a small-seeded grain crop with a dramatic history. Once a staple in the diet of the Aztec Indians, today it is grown throughout the world. In the United States much of the production is small-scale and organic, grown mainly for the natural and health food markets. There also has been steady use of the crop for breakfast cereals, snack foods, and mass-produced multigrain bread products. Amaranth is a broadleaf plant well-adapted to a range of arid and humid environments. As a crop it fits into many dryland rotations, performing well following wheat, proso millet, or other grain crops. …

Nf98-362 Chemical Weed Control In Tree Planting Projects: Part I - Pre-Emergence Herbicides, John Duplissis

University of Nebraska-Lincoln Extension: Historical Materials

This NebFact examines weed control in tree planting projects.

Nfs-1 Forestry Best Management Practices For Nebraska

University of Nebraska-Lincoln Extension: Historical Materials

A reference guide for loggers, landowners and managers.

Nebraska's Forest Resource

Forests cover 947,000 acres in Nebraska. Other land with scattered tree cover, including narrow wooded strips along streams, windbreaks, and wooded pasture lands, occupy an additional 1,252,000 acres. Managing Nebraska's forest lands can produce significant benefits without negative impacts; however, careless activities in woodlands can damage water resources, soils, wildlife habitat, aesthetic values, and even the ability to produce future benefits.

Nf97-321 Converting Crp To Cropland In The Nebraska Panhandle, Drew J. Lyon, Tom Holman

University of Nebraska-Lincoln Extension: Historical Materials

This NebFact discusses techniques for converting CRP ground to cropland, including minimum tillage and crop rotations.

Ec96-1555 Insect Pest Management Strategies For Yards And Gardens, Frederick P. Baxendale, Robert J. Wright

University of Nebraska-Lincoln Extension: Historical Materials

A growing awareness of problems associated with overusing pesticides has prompted many home gardeners and landscape managers to seek alternative methods of insect control. Integrated pest management (IPM) uses suitable methods in a compatible manner to maintain pest densities below levels of unacceptable injury.

IPM principles can be applied to all pest groups (insects, mites, weeds, plant diseases and vertebrates), and urban as well as agricultural settings. This publication will discuss how integrated pest management can be applied to insect and mite management in yards and gardens.

G96-1308 Management Of Eastern Redcedar On Grasslands, John Ortmann, James L. Stubbendieck, George Pfeiffer, Robert A. Masters, Walter H. Schacht

University of Nebraska-Lincoln Extension: Historical Materials

Developing an integrated control program including prescribed burning, herbicides, and cutting may be the best way to control eastern redcedar in Nebraska, according to recent research. Eastern redcedar is a serious threat to grassland productivity. Some control methods may be too expensive to use on grasslands, but in many cases, an integrated approach combining fire with more intensive follow-up methods will provide reasonable control at an acceptable cost.

G95-1241 Annual Broadleaf Weed Control In Winter Wheat (Revised January 1999), Gail` A. Wicks, Robert N. Klein, Alex Martin, Drew J. Lyon

University of Nebraska-Lincoln Extension: Historical Materials

This guide discusses preventive, cultural, and chemical weed control in winter wheat. The best weed control is obtained by using a combination of these methods. Winter and summer annual broadleaf weeds have an important economic impact on Nebraska winter wheat. They compete with winter wheat for water, light, space, and nutrients, reducing Nebraska winter wheat yields by an estimated 10 percent each year. The dollar loss, with wheat at $2.50 per bushel, is over $2.1 million per year. Weeds also slow harvest and increase combine repair costs. Producers may be docked at the elevator for excessive grain moisture and/or weed …

G93-1145 Management Of The Army Cutworm And Pale Western Cutworm, Gary L. Hein, John B. Campbell, Stephen D. Danielson, James A. Kalisch

University of Nebraska-Lincoln Extension: Historical Materials

This NebGuide describes the life cycle of the army cutworm and pale western cutworm, and provides recommendations for management.

The army cutworm, Euxoa auxiliaris, and the pale western cutworm, Agrotis orthogonia, are sporadic pests that are distributed throughout the Great Plains. The army cutworm can be found throughout Nebraska, but is more common in the western half of the state. Because of the drier environment, the pale western cutworm is found only in the western third of Nebraska. Both cutworms can feed on a vast array of crops and weeds. Their major economic impact is limited to winter …

G93-1158 Questions And Answers About Atrazine, Fred Roeth, S.D. Comfort

University of Nebraska-Lincoln Extension: Historical Materials

This NebGuide addresses some of the current concerns about atrazine and water quality. Included are some questions and answers about atrazine regarding toxicity, EPA guidelines, presence in water supplies, weed resistance and best management practices. What is atrazine? Atrazine is a herbicide that selectively controls broadleaf (dicot) weeds, such as pigweed, cocklebur, velvetleaf and certain grass weeds in fields of corn and sorghum. Selective control means that the target weeds are controlled, with little or no injury to the crop. Atrazine is well tolerated by actively growing corn and sorghum, which absorb and metabolize the herbicide and thereby detoxify it.

G92-1109 Musk Thistle, Robert Wilson, Fred Roeth, Alex Martin

University of Nebraska-Lincoln Extension: Historical Materials

The history, identification and chemical, mechanical and cultural control of musk thistle are discussed. Musk thistle is a major problem for many Midwestern landowners. It reduces forage yields by robbing moisture and plant food from palatable grasses. Livestock refuse to enter heavily infested areas and will not graze close to the spiny plants. Since its emergence as a serious weed problem in the late 1940s, musk thistle has invaded thousands of acres of Nebraska pastureland and even occurs in some cultivated fields. It has moved from the Kansas border to the South Dakota border and as far west as Colorado …

G92-1081 Factors That Affect Soil-Applied Herbicides, R. S. Moomaw, Robert N. Klein, Alex Martin, Fred Roeth, P.J. Shea, G.A. Wicks, R. G. Wilson

University of Nebraska-Lincoln Extension: Historical Materials

Characteristics of soil-applied herbicides are discussed, including site of uptake by weeds, solubility, adsorption, persistence, leaching potential, photodecomposition, and volatility. For best performance, preemergence and preplant herbicides must be placed in the top 0 to 3 inches of soil. Placement is important because the herbicide must enter the germinating weed seedling in order to kill it. Herbicides can be blended into the soil by mechanical incorporation, rainfall, or sprinkler irrigation, depending on the herbicide. Herbicide characteristics that determine their performance are site of uptake by weeds, solubility, adsorption, persistence, leaching potential, photodecomposition, and volatility. An understanding of these factors will …

Ec92-124 Nebraska Handbook Of Range Management, James L. Stubbendieck, Patrick E. Reece

University of Nebraska-Lincoln Extension: Historical Materials

Every Nebraskans should be interested in rangeland. The plants, soil, and water are the foundation of Nebraska's economy and quality of life. Rangeland is one of Nebraska's most important and valuable natural resources because it:

• produces forage for livestock and wild game;

• provides a varied habitat for many wildlife species;

• protects the soil from wind and water erosion;

• preserves a "germplasm bank" for many plant species that may become important for yet unknown uses;

• purifies and enhances the environment by cleasing the air, filtering the runoff to streams, increasing the intake of precipitation, and aiding …

G90-983 Equipment Adjustments For Herbicide Incorporation, Robert Grisso, Elbert C. Dickey, Alex Martin

University of Nebraska-Lincoln Extension: Historical Materials

This NebGuide discusses how to operate liquid herbicide application equipment on tillage implements.

Heightened concerns for energy and soil conservation have caused producers to reduce the number of secondary tillage operations while trying to maintain satisfactory incorporation of herbicides. Many herbicides are carried into the soil by rainfall or sprinkler irrigation and do not require mechanical incorporation. However, some soil-applied herbicides require mechanical incorporation to reduce volatility and photodecomposition losses. These are Eradicane, Sutan+ and Treflan.

G89-899 Weed Control In No-Till Corn, Grain Sorghum And Soybean Production, R.S. Moomaw, Alex Martin, R.N. Stougaard, Fred Roeth, G.A. Wicks, Robert N. Klein, Paul J. Jasa

University of Nebraska-Lincoln Extension: Historical Materials

Tips for successful no-till weed control, weed control principles for no-till row crop production, and no-till row crops planted into legume or small grain residues are covered here. Soil erosion by wind and water is a strong societal concern in our state and nation. Current estimates are that more than 100 million tons of topsoil are eroded annually in Nebraska, with 75 percent of that coming from row crop areas. Nebraska farmers have been implementing changes in their crop production practices to reduce soil erosion.