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Full-Text Articles in Physical Sciences and Mathematics

Consequences Of Shifts In Abundance And Distribution Of American Chestnut For Restoration Of A Foundation Forest Tree, Harmony J. Dalgleish, Charles Dana Nelson, John A. Scrivani, Douglass F. Jacobs Dec 2015

Consequences Of Shifts In Abundance And Distribution Of American Chestnut For Restoration Of A Foundation Forest Tree, Harmony J. Dalgleish, Charles Dana Nelson, John A. Scrivani, Douglass F. Jacobs

Forestry and Natural Resources Faculty Publications

Restoration of foundation species, such as the American chestnut (Castanea dentata) that was devastated by an introduced fungus, can restore ecosystem function. Understanding both the current distribution as well as biogeographic patterns is important for restoration planning. We used United States Department of Agriculture Forest Service Forest Inventory and Analysis data to quantify the current density and distribution of C. dentata. We then review the literature concerning biogeographic patterns in C. dentata. Currently, 431 ± 30.2 million stems remain. The vast majority (360 ± 22 million) are sprouts < 2.5 cm dbh. Although this number is approximately 10% of the estimated pre-blight population, blight has caused a major shift in the size structure. The current-day population has a larger range, particularly west and north, likely due to human translocation. While climate change could facilitate northward expansion, limited seed reproduction makes this unlikely without assisted migration. Previous research demonstrates that the current, smaller population contains slightly higher genetic diversity than expected, although little information exists on biogeographic patterns in the genetics of adaptive traits. Our research provides a baseline characterization of the contemporary population of C. dentata, to enable monitoring stem densities …


Characteristics Of Kentucky’S Nursery And Greenhouse Industries [2015], Dewayne L. Ingram, Winston Dunwell, Alan Hodges Dec 2015

Characteristics Of Kentucky’S Nursery And Greenhouse Industries [2015], Dewayne L. Ingram, Winston Dunwell, Alan Hodges

Agriculture and Natural Resources Publications

The nursery and greenhouse industry in Kentucky is diverse and contributes significantly to the local and state economy. This industry represents the largest segment of Kentucky’s sales of horticultural products and is comprised almost completely of farm families. Nursery and greenhouse operations have historically been characterized as separate production systems and crops. However, today primary nurseries may also have greenhouses and/or produce herbaceous perennials and annuals to satisfy their customer base. On the other hand, many primary greenhouse firms that once grew mostly annuals and potted flowering crops have expanded their product line to include herbaceous perennials, often finished in …


Economic Impacts Of The Kentucky Green Industry [2015], Dewayne L. Ingram, Alan Hodges Dec 2015

Economic Impacts Of The Kentucky Green Industry [2015], Dewayne L. Ingram, Alan Hodges

Agriculture and Natural Resources Publications

The green industry, comprised of firms engaged in the production and use of landscape and floral crops and related supplies and equipment and the design, construction, and maintenance of landscapes, has a significant impact on Kentucky’s economy. Green-industry enterprise owners, managers, and employees should be aware of their economic impacts, and policy makers and other state leaders need to know the importance of this industry as potential laws, regulations and resource allocations are considered. This publication is intended to provide a brief summary of the 2013 economic impacts of the green industry in Kentucky.


Introduction To Wood Structure And Characteristics, Terry Conners Dec 2015

Introduction To Wood Structure And Characteristics, Terry Conners

Agriculture and Natural Resources Publications

Wood is identified using the features and tools that are appropriate to the size of the sample. Large timbers are identified by looking at the color, the appearance of the end and side grain, whether a saw cuts cleanly or leaves lots of splinters behind, whether the wood has straight or curly drying cracks, and so forth. The hardness and density provide valuable information as well. For smaller pieces of wood, it’s more practical to look directly at the wood cells with a 10X hand lens (also called a loupe). Different species have different characteristics and combinations of these features …


Distinguishing Softwoods From Hardwoods, Terry Conners Dec 2015

Distinguishing Softwoods From Hardwoods, Terry Conners

Agriculture and Natural Resources Publications

Softwood and hardwood trees are made up of different types of cells. With just a little magnification, it’s easy to see that softwood growth rings look different from hardwood growth rings. Additionally, growth rings don’t look the same for all of the trees, and the growth ring appearance is one of the things we will look at to identify wood.


Grain Patterns And Growth Rings, Terry Conners Dec 2015

Grain Patterns And Growth Rings, Terry Conners

Agriculture and Natural Resources Publications

The preceding article, "Identifying Wood–A Primer for Everyone, Part 3: Distinguishing Softwoods from Hardwoods" (FOR-125), described how to distinguish softwoods from hardwoods, and that’s the first step in identifying an unknown piece of wood. At this point, additional terminology is necessary to further distinguish between species, and I'll begin by talking about the different sides of a hypothetical piece of wood. Frequently you need to be able to observe wood cells from a particular perspective, and you will need to know where to look for different features on your sample. It’s also very helpful to develop a kind of “visual …


The First Separation Of Softwood Species, Terry Conners Dec 2015

The First Separation Of Softwood Species, Terry Conners

Agriculture and Natural Resources Publications

Just making the separation between softwoods and hardwoods doesn’t help much in identifying wood species; that would be sort of like identifying children by their hair color. Let’s look at the next level of wood features that you need to be able to recognize.


First Steps In Identifying Wood, Terry Conners Dec 2015

First Steps In Identifying Wood, Terry Conners

Agriculture and Natural Resources Publications

Wood samples need to be identified for all sorts of reasons, and they come in all shapes, sizes and conditions. I’ve received samples that were sound, samples that were waterlogged, samples that were rotted or otherwise degraded, painted samples, furniture samples, even samples containing wood preservatives. Most of the samples I receive have a North American origin, but I also receive pieces from art museums and antique dealers that can originate from just about anywhere. This sometimes means that identifying the sample by a common name alone doesn’t provide enough information.


2016 Weed Control Recommendations For Kentucky Grain Crops, James R. Martin, Jonathan D. Green Nov 2015

2016 Weed Control Recommendations For Kentucky Grain Crops, James R. Martin, Jonathan D. Green

Agriculture and Natural Resources Publications

The use of herbicides suggested in this publication is based on research at the Kentucky Agricultural Experiment Station and elsewhere. We have given what we believe to be the most effective herbicides, with the most suitable rates and times of application. Use of trade or brand names in this publication does not imply approval of the product to the exclusion of others which may be of similar or suitable composition.


Vegetable Production Guide For Commercial Growers, 2016-17, Shubin Saha, Emily Pfeufer, Ricardo Bessin, Shawn Wright, John Strang Nov 2015

Vegetable Production Guide For Commercial Growers, 2016-17, Shubin Saha, Emily Pfeufer, Ricardo Bessin, Shawn Wright, John Strang

Agriculture and Natural Resources Publications

Successful vegetable production generally requires the grower to make daily decisions regarding pest management, irrigation, and cultural practices. Would-be growers unwilling to make serious investments of time (and money) should not attempt to expand beyond a space at the farmers’ market. It is important for vegetable growers to have a market outlet for their product before they choose to start production. Good marketing plans start with the customer and work backward to production. Potential growers should first determine exactly what buyers want, how they want it, and when they want it. They then must determine how these crops should be …


Uk Ag Equine Programs 2016 Calendar: A 12-Month Planning Calendar For The Care And Use Of Your Horses, Jason R. Philips, Glenn Mackie, Don Sorrell, Nicholas L. Carter, Paula A. Jerrell, Brian Newman, Daniel O. Wilson, Christopher Jeffcoat, Karen Douglas, Katheryn Cerny, Fernanda Camargo, Robert Coleman, Essie Rodgers, Jim Smith Oct 2015

Uk Ag Equine Programs 2016 Calendar: A 12-Month Planning Calendar For The Care And Use Of Your Horses, Jason R. Philips, Glenn Mackie, Don Sorrell, Nicholas L. Carter, Paula A. Jerrell, Brian Newman, Daniel O. Wilson, Christopher Jeffcoat, Karen Douglas, Katheryn Cerny, Fernanda Camargo, Robert Coleman, Essie Rodgers, Jim Smith

Agriculture and Natural Resources Publications

The information in this calendar is provided to aid owners in planning for the care and use of their horses for the whole year.

When necessary, information is discussed in the month prior to application to allow horse owners adequate time to plan for activities such as weed control, soil and feed testing, vaccinations, etc.

Contact your local veterinarian for health-related issues and your county extension ANR, 4-H, or FCS agent for further information. County office phone numbers are listed at the end of the calendar.


Producer’S Guide To Pasture-Based Beef Finishing, Gregory S. Halich, Jeff Lehmkuhler, Gregg Rentfrow, Fred Martz, S. Ray Smith, Lee Meyer Oct 2015

Producer’S Guide To Pasture-Based Beef Finishing, Gregory S. Halich, Jeff Lehmkuhler, Gregg Rentfrow, Fred Martz, S. Ray Smith, Lee Meyer

Agriculture and Natural Resources Publications

Beef cattle were routinely finished locally in Kentucky and other parts of the upper south before the 1950s, primarily on pasture with some grain or by-products from distilleries and grain processing mills. Cattle were typically born, raised, and finished on the same farm then sent to a local butcher where the meat was sold in nearby communities and cities. After the Second World War grain and transportation costs decreased dramatically and supermarket chains that required a large, steady supply channel were established. The combined effect of these changes made finishing in large centralized locations more economical. Over the next couple …


Heterogeneous Oxidation Of Catechol, Elizabeth A. Pillar, Ruixin Zhou, Marcelo I. Guzman Sep 2015

Heterogeneous Oxidation Of Catechol, Elizabeth A. Pillar, Ruixin Zhou, Marcelo I. Guzman

Chemistry Faculty Publications

Natural and anthropogenic emissions of aromatic hydrocarbons from biomass burning, agro-industrial settings, and fossil fuel combustion contribute precursors to secondary aerosol formation (SOA). How these compounds are processed under humid tropospheric conditions is the focus of current attention to understand their environmental fate. This work shows how catechol thin films, a model for oxygenated aromatic hydrocarbons present in biomass burning and combustion aerosols, undergo heterogeneous oxidation at the air–solid interface under variable relative humidity (RH = 0–90%). The maximum reactive uptake coefficient of O3(g) by catechol γO3 = (7.49 ± 0.35) × 10–6 occurs for …


Managing Precision Dairy Farming Technologies, Barbara Alice Wadsworth, Amanda Stone, Lauren M. Mayo, Nicky Tsai, Jeffrey M. Bewley Sep 2015

Managing Precision Dairy Farming Technologies, Barbara Alice Wadsworth, Amanda Stone, Lauren M. Mayo, Nicky Tsai, Jeffrey M. Bewley

Agriculture and Natural Resources Publications

Precision dairy farming is the use of technologies to measure physiological, behavioral, and production indicators of individual animals to improve management strategies and farm performance. These systems have the potential to detect disease and estrus and to evaluate cow comfort by monitoring activity, feeding time, lying time, mounting activity, real-time location, reticulorumen pH, rumination time, and body temperature.

The data provided by a precision dairy farming device is only valuable if it records the data properly for the right cow and is used by the producer. This factsheet will describe problems that researchers at the University of Kentucky have experienced …


Turfgrasses Of Kentucky, Gregg Munshaw Aug 2015

Turfgrasses Of Kentucky, Gregg Munshaw

Agriculture and Natural Resources Publications

Roughly 7,500 grass species are grown around the world, but only 14 species are adapted as turfgrasses that have been used extensively. Kentucky is situated in the transitional climatic zone of the United States, the middle point between the cool north and the warm south, with warm summers and cool winters. Because of its unusual climate, no single grass is suitable for all situations and locations.


All-Weather Surfaces For Cattle Watering Facilities, Stephen F. Higgins, Kylie Schmidt, Donald J. Stamper, Kevin Laurent Jul 2015

All-Weather Surfaces For Cattle Watering Facilities, Stephen F. Higgins, Kylie Schmidt, Donald J. Stamper, Kevin Laurent

Agriculture and Natural Resources Publications

A livestock watering area includes a watering facility and the heavy-use-area (HUA) surrounding it. Without protection, the HUA can develop surface depressions. Surface depressions can render the watering facility inaccessible and no longer frost-proof. Surface depressions also collect rainwater and excrement, creating mud and conditions adverse to livestock health (Figure 1).


Slaframine Toxicosis Or “Slobbers” In Cattle And Horses, Michelle Arnold, S. Ray Smith Jul 2015

Slaframine Toxicosis Or “Slobbers” In Cattle And Horses, Michelle Arnold, S. Ray Smith

Agriculture and Natural Resources Publications

An exceptionally wet summer weather pattern favors the growth of fungi on plants in the field and increases the risk for production of mycotoxins. Mycotoxins are naturally occurring compounds, some of which are toxic to cattle and horses, produced by fungi invading plant material. In the late 1940s and through the 1950s, beef and dairy producers and horse owners reported outbreaks of excessive salivation (slobbering) in cattle and horses associated with the consumption of second-cutting red clover (Trifolium pratense) and occasionally other legumes in the form of hay, pasture, or silage. It was not until the 1960s that …


Acute Or Atypical Interstitial Pneumonia (Aip), Michelle Arnold, Jeff Lehmkuhler Jul 2015

Acute Or Atypical Interstitial Pneumonia (Aip), Michelle Arnold, Jeff Lehmkuhler

Agriculture and Natural Resources Publications

Acute or atypical interstitial pneumonia (AIP) is terminology used by veterinary pathologists to describe a characteristic pattern of damage in the lungs of cattle. At necropsy, the first indication of AIP-affected lungs is they fill the thorax and do not collapse like normal lungs when the chest cavity is opened. On further investigation, the AIP lungs are found to be semi-firm with a rubbery texture; not hard and consolidated as occurs in bacterial bronchopneumonia. Large air bubbles are found between portions of the lung (see Figure 1, “interlobular” or “bullous” emphysema) and the cut surface of the lung may appear …


Staggers (Tremorgenic Syndrome), Michelle Arnold Jul 2015

Staggers (Tremorgenic Syndrome), Michelle Arnold

Agriculture and Natural Resources Publications

“Staggers” is an all-inclusive term for a group of nervous system disorders caused by indole-diterpenoid mycotoxins produced by various types of fungi on forages. These mycotoxins are collectively known as “tremorgens” (Table 1), and they may be found in several types of grasses at varying stages of maturity. The three main grass types associated with tremorgenic syndrome are Paspalum spp. (dallisgrass and bahiagrass), Cynodon dactylon (bermudagrass) and Lolium perenne (perennial ryegrass). Clinical signs are characterized by tremors and incoordination that tend to worsen with excitement or movement.


Guía De Monitoreo De Mip Para Plagas Comunes De Los Cultivos Cucurbitáceos En Kentucky, Kenneth W. Seebold, Timothy Coolong, Terry Jones, John Strang, Ricardo Bessin, Cheryl A. Kaiser Jul 2015

Guía De Monitoreo De Mip Para Plagas Comunes De Los Cultivos Cucurbitáceos En Kentucky, Kenneth W. Seebold, Timothy Coolong, Terry Jones, John Strang, Ricardo Bessin, Cheryl A. Kaiser

Agriculture and Natural Resources Publications

Mucho antes de que el término “sostenible” se hiciera tan conocido, los agricultores ya estaban implementando prácticas sostenibles en forma de estrategias de manejo integrado de plagas. El MIP usa una combinación de métodos biológicos, de cultivo, físicos, y químicos que reducen y/o manejan las poblaciones de pestes. Estas estrategias son usadas para minimizar los riesgos ambientales, de costos, y peligros a la salud. Las plagas son manejadas para reducir su impacto negativo en el cultivo, aunque raramente las pestes son eliminadas.


Practicing Good Stewardship When Applying Herbicides For Pasture Weed Control, Jonathan D. Green May 2015

Practicing Good Stewardship When Applying Herbicides For Pasture Weed Control, Jonathan D. Green

Agriculture and Natural Resources Publications

Various methods and strategies can be used to combat weed problems in pasture fields. These include mechanical and cultural practices such as mowing or clipping fields, maintaining a good soil fertility program, grazing methods, and other management practices that promote the growth of desirable forage grasses which in turn compete against weeds. Herbicides can be the best alternative to effectively control several troublesome broadleaf weeds. However, it is important to understand the proper use of herbicides and practice good stewardship. Below are some important tips to consider when choosing and applying a herbicide product.


Aquatic Macroinvertebrates: Biological Indicators Of Stream Health, Carmen T. Agouridis, Evan T. Wesley, Tyler M. Sanderson, Blake L. Newton May 2015

Aquatic Macroinvertebrates: Biological Indicators Of Stream Health, Carmen T. Agouridis, Evan T. Wesley, Tyler M. Sanderson, Blake L. Newton

Agriculture and Natural Resources Publications

Streams are an important part of the landscape. Streams transport water, sediment and energy; provide habitat for aquatic life and support terrestrial life; provide a place for recreation; and in many cases serve as a water supply. The health of streams—or their ability to perform these important functions—is dependent on the conditions of the watersheds which they drain. Changes in land use within a watershed can affect a stream’s health (Figure 1).


Herbicide Recommendations For Weed Control In Kentucky Bluegrass And Tall Fescue Lawns For Professional Applicators, Gregg Munshaw, Jonathan D. Green, Michael Barrett Mar 2015

Herbicide Recommendations For Weed Control In Kentucky Bluegrass And Tall Fescue Lawns For Professional Applicators, Gregg Munshaw, Jonathan D. Green, Michael Barrett

Agriculture and Natural Resources Publications

The best method to control weeds is to grow a dense and healthy lawn. This objective should be primary for turf professionals.


Fundamental Principles Of Plant Pathology For Agricultural Producers [2015], Paul C. Vincelli Mar 2015

Fundamental Principles Of Plant Pathology For Agricultural Producers [2015], Paul C. Vincelli

Agriculture and Natural Resources Publications

All crop plants produced in Kentucky have the potential to become diseased under certain conditions. Diseases of crops can affect yield and/or quality of the harvested commodity, which can impact profitability and increase the risks of farming.


Planning A Zero-Waste Event, Ashley Osborne Feb 2015

Planning A Zero-Waste Event, Ashley Osborne

Agriculture and Natural Resources Publications

Today the average American creates a little over 4 pounds of waste per day. Of that, roughly 1 ½ pounds is recycled or composted, meaning that more than 2½ pounds of waste per person per day is discarded to landfills or combusted (with energy recovery).


Reductions Of Wheat Yield And Yield Components And Nitrogen Loss Following Frozen Soil Nitrogen Applications, Carrie Ann Knott, Edwin L. Ritchey, Lloyd W. Murdock Jan 2015

Reductions Of Wheat Yield And Yield Components And Nitrogen Loss Following Frozen Soil Nitrogen Applications, Carrie Ann Knott, Edwin L. Ritchey, Lloyd W. Murdock

Plant and Soil Sciences Research Report

Most wheat producers in Kentucky apply nitrogen (N) as a split application. The first N increment is applied when wheat plants begin actively growing (green-up) in late winter, which is typically in mid- February between growth stages Feekes 2 to 3. The second N increment typically occurs in March when wheat is between Feekes 5 to 6. Many producers in Kentucky, especially Western Kentucky, have become accustomed to beginning first N applications in late January when the ground is frozen and the wheat is still dormant. This practice allows them to apply N to large acreages of wheat while avoiding …


An Optical Sprayer Nozzle Flow Rate Sensor, Joseph S. Dvorak, Luke E. Bryant Jan 2015

An Optical Sprayer Nozzle Flow Rate Sensor, Joseph S. Dvorak, Luke E. Bryant

Biosystems and Agricultural Engineering Faculty Publications

Ensuring proper flow rates from each nozzle on an agricultural sprayer has become even more important as advances continue to be made in precision application technology. In this article, we describe the structure and testing of a sensor technology based on optical cross-correlation to determine the flow rate of individual sprayer nozzles. An advantage of this technology is that it does not require that impellers or other components be placed in the flow, which could cause plugging. The only moving part in the entire system is a solenoid used to inject a tracer dye. The objective of this study was …


Kentucky Water Resources Research Institute Annual Technical Report Fy 2014, Kentucky Water Resources Research Institute, University Of Kentucky Jan 2015

Kentucky Water Resources Research Institute Annual Technical Report Fy 2014, Kentucky Water Resources Research Institute, University Of Kentucky

KWRRI Annual Technical Reports (USGS’s 104b Grant Program)

The 2014 Annual Technical Report for Kentucky consolidates reporting requirements for the Section 104(b) base grant award into a single document that includes: 1) a synopsis of each research project that was conducted during the period, 2) citations for related publications, reports, and presentations, 3) a description of information transfer activities, 4) a summary a student support during the reporting period, and 5) notable awards and achievements during the year.


Determining Soil Texture By Feel, Edwin L. Ritchey, Joshua M. Mcgrath, David Gehring Jan 2015

Determining Soil Texture By Feel, Edwin L. Ritchey, Joshua M. Mcgrath, David Gehring

Agriculture and Natural Resources Publications

Soil texture refers to the proportion of sand, silt, and clay in a soil. Texture influences almost every aspect of soil use, both in agricultural and engineering applications, and even how natural ecosystems function. Many scientists consider soil texture the most important soil property as it can influence soil/water relationships, gas exchange, and plant nutrition. Accurately determining soil texture in a lab requires time and money; therefore, it is often necessary to estimate soil texture in the field by feel, which can be very accurate if done correctly.


Organic Corn Production In Kentucky, Michael Bomford, Lee Meyer, Thomas Sikora, William Martin, Sam Mcneill, Michael D. Montross, Edwin L. Ritchey, Chad Lee Jan 2015

Organic Corn Production In Kentucky, Michael Bomford, Lee Meyer, Thomas Sikora, William Martin, Sam Mcneill, Michael D. Montross, Edwin L. Ritchey, Chad Lee

Agriculture and Natural Resources Publications

The number of organic dairy cows in Kentucky has been steadily increasing for years, yet there’s not enough organic corn produced in the state to feed the growing herds. In fact, most of the organic corn consumed in Kentucky is produced outside of the state. The growing organic livestock and poultry industries in Kentucky face the same feed constraints. In short, a new market has developed in the state, but few local farmers are taking advantage of it.