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Full-Text Articles in Agriculture

Tree Biomass – A Fragile Carbon Storage In Old-Growth Birch And Aspen Stands In Hemiboreal Latvia, Laura Ķēniņa, Didzis Elferts, Ieva Jaunslaviete, Endijs Bāders, Guntars Šņepsts, Āris Jansons Dec 2022

Tree Biomass – A Fragile Carbon Storage In Old-Growth Birch And Aspen Stands In Hemiboreal Latvia, Laura Ķēniņa, Didzis Elferts, Ieva Jaunslaviete, Endijs Bāders, Guntars Šņepsts, Āris Jansons

Aspen Bibliography

Birch (Betula pendula Roth, Betula pubescens Ehrh.) and European aspen (Populus tremula L.) stands dominate the deciduous forests of Northern Europe. Due to increasing forest protections, more deciduous stands will reach the old-growth stage. Thus, data on the carbon storage potential in such areas are essential. We aimed to establish a benchmark for carbon stocks of the main carbon pools in old-growth deciduous hemiboreal stands. Carbon pools were calculated from measurements in forty old-growth (104–148 years-old) deciduous stands in forests on fertile mineral soil. The carbon stock in these stands is distributed across tree biomass (~ 60%), mineral soil (~ …


Easy Calibration For Backpack And Canister (Handheld) Sprayers, Cody Zesiger, Kalen Taylor, Corey Ransom, Earl Creech, Matt Yost Dec 2022

Easy Calibration For Backpack And Canister (Handheld) Sprayers, Cody Zesiger, Kalen Taylor, Corey Ransom, Earl Creech, Matt Yost

All Current Publications

When applying pesticides, fertilizers, and other chemicals, the applicator should know the amount of chemical applied to the treated area. Calibration is a method an applicator can use to measure and set the application rate. If sprayers are not properly calibrated, it can result in over or under application of chemicals, causing damage, reduced pest control, and potential safety concerns. Making the effort to properly mix chemicals and calibrate sprayers can save money and increase treatment effectiveness. This fact sheet provides simple guidelines for calibrating backpack and canister sprayers.


Easy Calibration For Boom Sprayers, Cody Zesiger, Kalen Taylor, Corey Ransom, Earl Creech, Matt Yost Dec 2022

Easy Calibration For Boom Sprayers, Cody Zesiger, Kalen Taylor, Corey Ransom, Earl Creech, Matt Yost

All Current Publications

Calibrating spray equipment is an important first step when applying pesticides, fertilizers, and other chemicals. If nozzles are not properly calibrated, it can result in over or under application of chemicals, causing crop damage, reduced pest control, and potential safety concerns. Making the effort to properly mix chemicals and calibrate sprayers can save money and headaches in the long run. This fact sheet provides simple guidelines for calibrating boom sprayers.


Aspen Leaves As A "Chemical Landscape" For Fungal Endophyte Diversity - Can Nitrogen And Herbivory Shape The Community Composition In Controlled Conditions?, Johanna Witzell, Vicki Huizu Guo Decker, Marta Agostinelli, Carmen Romeralo Tapia, Michelle Cleary, Benedicte Riber Albrectsen Dec 2022

Aspen Leaves As A "Chemical Landscape" For Fungal Endophyte Diversity - Can Nitrogen And Herbivory Shape The Community Composition In Controlled Conditions?, Johanna Witzell, Vicki Huizu Guo Decker, Marta Agostinelli, Carmen Romeralo Tapia, Michelle Cleary, Benedicte Riber Albrectsen

Aspen Bibliography

The endophytic microbiome may influence the ecological performance of plants, including forest trees. Various abiotic and biotic factors may shape the endophyte communities directly but also indirectly, by modifying the quality of host plants as a substrate. We hypothesized that potentially antifungal or fungistatic condensed tannins (CTs) would determine the quality of aspen (Populus tremula) leaves as a substrate for endophytic fungi. By subjecting the plants to nitrogen fertilization (N) or herbivory (H; leaf beetles) we aimed to change the internal “chemical landscape”, especially the CT levels, in aspen leaves. We expected that this would lead to changes in the …


Pests Of Hemp In Utah, Marion Murray, Macahl Evans, Claudia Nischwitz, Austin Taylor, Cody Zesiger Dec 2022

Pests Of Hemp In Utah, Marion Murray, Macahl Evans, Claudia Nischwitz, Austin Taylor, Cody Zesiger

All Current Publications

This guide includes information on insect and disease pests of hemp, organized by pest group. Much of the content is a result of a two-year arthropod and plant disease survey of field-grown hemp operations in northern Utah. Some pests included in this guide were not found in that survey but may be likely to occur in the future. Beneficials and natural enemies are also covered, and information on pesticides is included.


Ten Considerations For Solar-Powered Irrigation In Utah, Ngonidzashe Mufute, Matt Yost, Burdette Barker, Kalen Taylor, Mark Nelson, Randall Violett, Jody Gale Dec 2022

Ten Considerations For Solar-Powered Irrigation In Utah, Ngonidzashe Mufute, Matt Yost, Burdette Barker, Kalen Taylor, Mark Nelson, Randall Violett, Jody Gale

All Current Publications

This fact sheet outlines considerations for using solar-powered irrigation in Utah:

• Solar powered irrigation (SPI) is becoming more cost effective and practical to consider on the farm as the cost of alternative sources of energy are rising.
• Irrigators can now benefit from incentives such as tax credits to help offset costs.
• Investing in solar provides more independence from price fluctuations and energy shortages.
• Considerations for SPI systems include energy demand of the irrigation system, type and value of crops grown, available incentives and support, cost and accessibility of alternative energy sources, and multiple uses of the …


The Backyard Garden - Cole Crops Pests, Nick Volesky, Marion Murray Nov 2022

The Backyard Garden - Cole Crops Pests, Nick Volesky, Marion Murray

All Current Publications

This fact sheet contains information about pests and diseases that affect cole crops. Cole crops are plants that belong to the mustard (Brassica) family, including hardy, cool-season crops such as broccoli, kohlrabi, cabbage, rutabaga, cauliflower, kale, Brussels sprouts, and turnips. The fact sheet offers general information and guidance on severity, other hosts, symptoms, and management.


The Backyard Garden - Leafy Greens Pests, Nick Volesky, Marion Murray Nov 2022

The Backyard Garden - Leafy Greens Pests, Nick Volesky, Marion Murray

All Current Publications

This fact sheet provides information about the diseases that affect leafy greens. It includes general information, other hosts, disease symptoms to watch for, and management options.


Sorghum-Sudangrass Production Guide, Dakota Boren, Matt Yost, Luree Johnson, Tina Sullivan, Earl Creech, Grant Cardon, Corey Ransom, Randall Violett, Cheyenne Reid, Cody Zesiger, Kalen Taylor, Jacob Hadfield, Michael Pace, Jody Gale Oct 2022

Sorghum-Sudangrass Production Guide, Dakota Boren, Matt Yost, Luree Johnson, Tina Sullivan, Earl Creech, Grant Cardon, Corey Ransom, Randall Violett, Cheyenne Reid, Cody Zesiger, Kalen Taylor, Jacob Hadfield, Michael Pace, Jody Gale

All Current Publications

Sudex is a warm-season forage crop that performs well in Utah’s dry climate due to its drought tolerance. It can be especially useful during drought years or when irrigation supplies are limited. As well as being a high-quality feed, Sudex has many benefits, including weed suppression and soil-building properties. Although there are concerns for prussic acid and nitrate poisoning, these concerns can be reduced and often eliminated with proper management. This fact sheet provides information to producers about using Sudex and best production practices. Much of the information may also apply to forage sorghum and a few of the major …


Assisted Migration Is Plausible For A Boreal Tree Species Under Climate Change: A Quantitative And Population Genetics Study Of Trembling Aspen (Populus Tremuloides Michx.) In Western Canada, Chen Ding, Jean S. Brouard Oct 2022

Assisted Migration Is Plausible For A Boreal Tree Species Under Climate Change: A Quantitative And Population Genetics Study Of Trembling Aspen (Populus Tremuloides Michx.) In Western Canada, Chen Ding, Jean S. Brouard

Aspen Bibliography

A novel method was tested for improving tree breeding strategies that integrate quantitative and population genetics based on range-wide reciprocal transplant experiments. Five reciprocal common garden tests of Populus tremuloides were investigated including 6450 trees across western Canada focusing on adaptation traits and growth. Both genetic parameters and home-site transplant models were evaluated. We found a genetic trade-off between growth and early spring leaf flush and late fall senescence. Coefficients of phenotypic variation (CVp) of cell lysis (CL), a measure of freezing injury, shrank from 0.28 to 0.10 during acclimation in the fall, and the CVp slope versus …


Values: Helping Agricultural Producers Find Motivation By Focusing On What Matters, Jacob D. Gossner, Elizabeth Fauth, Tasha Howard Oct 2022

Values: Helping Agricultural Producers Find Motivation By Focusing On What Matters, Jacob D. Gossner, Elizabeth Fauth, Tasha Howard

All Current Publications

This fact sheet addresses the importance of tuning into values as a way of maintaining motivation and promoting mental health for agricultural producers.


Pando's Pulse: Vital Signs Signal Need For Course Correction At World-Renowned Aspen Forest, Paul C. Rogers Sep 2022

Pando's Pulse: Vital Signs Signal Need For Course Correction At World-Renowned Aspen Forest, Paul C. Rogers

Aspen Bibliography

Upland aspen (Populus spp.) forests contribute significantly to biodiversity in their circumboreal role as keystone species. As aspen ecosystems flourish or diminish, myriad dependent species follow suit. The 43-hectare Pando aspen (Populus tremuloides Michx.) clone in Utah, USA, is thought to be the largest living organism on earth, but is faltering due to chronic herbivory. Long-term resilience in aspen communities, including Pando, rests on successful recruitment of vegetative suckers that are nutritiously desirable to browsing ungulates. Here, I evaluate aspen reproduction alongside numerous vital indicators of Pando's status in the first trend assessment of this embattled iconic forest. …


County-Level View Of Irrigation Trends In Utah And The West, Matt Yost, Britta L. Schumacher, Luree Johnson, Emily Burchfield, Burdette Barker Sep 2022

County-Level View Of Irrigation Trends In Utah And The West, Matt Yost, Britta L. Schumacher, Luree Johnson, Emily Burchfield, Burdette Barker

All Current Publications

We explored water use management and trends in irrigated agriculture in the U.S. West using operator-level USDA-NASS Farm and Ranch Irrigation Survey (FRIS)/Irrigation and Water Management Survey (IWMS) data aggregated for the first time to the county instead of state scale. Our hope is that this study will guide water managers in developing regional conservation programs, inform extension and research initiatives related to irrigation, promote grower-informed water conservation education, and provide researchers with key information regarding if, how, and why growers consider water conservation in irrigation decision-making.


Ungulate Herbivores As Drivers Of Aspen Recruitment And Understory Composition Throughout Arid Montane Landscapes, Elizabeth S. Reikowski, Tyler Refsland, J. Hall Cushman Sep 2022

Ungulate Herbivores As Drivers Of Aspen Recruitment And Understory Composition Throughout Arid Montane Landscapes, Elizabeth S. Reikowski, Tyler Refsland, J. Hall Cushman

Aspen Bibliography

Herbivory by wild and domestic ungulates can influence tree recruitment and understory forest communities throughout the world. Herbivore-driven declines in tree recruitment have been observed for quaking aspen (Populus tremuloides), a foundation species whose health and management is recognized as a critical priority throughout much of its range. Livestock fencing is commonly used to promote aspen regeneration, but its effectiveness is rarely assessed, especially across large spatial scales. Using a livestock-reduction experiment, we evaluated the effects of ungulate herbivory on aspen in the Great Basin and southern Cascades, an expansive and environmentally heterogeneous region where aspen faces the …


Guide To Drought Tolerance Of Utah Field Crops, Matt Yost, Tina Sullivan, Dakota Boren, Luree Johnson, Melanie Mills, Earl Creech, Boyd Kitchen, Randall Violett Aug 2022

Guide To Drought Tolerance Of Utah Field Crops, Matt Yost, Tina Sullivan, Dakota Boren, Luree Johnson, Melanie Mills, Earl Creech, Boyd Kitchen, Randall Violett

All Current Publications

Crop variety selection is one of the most important choices on the farm. Crop genetics determine a significant portion of the yield potential and resource use efficiency. Crop types and genetics that use water more efficiently will become increasingly important as water becomes scarcer. Throughout Utah and the Western United States, water availability is decreasing due to various factors, including reduced snowpack and rapid urban growth. Alfalfa, other hay, small grains, and corn are grown on more acres than any other crops in Utah and much of the Intermountain West. These crops all have varieties, hybrids, and cultivars with the …


Precision Irrigation Guide For Center Pivots, Elisa Flint, Matt Yost, Troy Peters, Clara Anderson, Burdette Barker, Neil Hansen Aug 2022

Precision Irrigation Guide For Center Pivots, Elisa Flint, Matt Yost, Troy Peters, Clara Anderson, Burdette Barker, Neil Hansen

All Current Publications

This factsheet discusses the different variable rate irrigation (VRI) options for center pivots, when they might reduce water use and energy, produce higher crop yields, and when it might be unreasonable to expect these kinds of benefits.


Three Options For Mixing And Loading Spray Tanks, Kalen Taylor, Cody Zesiger, Corey Ransom, Earl Creech, Matt Yost Aug 2022

Three Options For Mixing And Loading Spray Tanks, Kalen Taylor, Cody Zesiger, Corey Ransom, Earl Creech, Matt Yost

All Current Publications

Correctly mixing a tank for chemical applications is something most farmers, ranchers, and home gardeners do regularly. However, understanding how to properly mix and calculate rates can be complicated. Follow one of the three options outlined in this fact sheet to accurately obtain application rates and mix chemical products safely and effectively.


Irrigation Water Loss And Recovery In Utah, Bradley S. Crookston, Troy Peters, Matt Yost, Burdette Barker Aug 2022

Irrigation Water Loss And Recovery In Utah, Bradley S. Crookston, Troy Peters, Matt Yost, Burdette Barker

All Current Publications

When deciding which irrigation systems to adopt, permit, or promote, it is important to consider how their efficiency and losses affect the water balance of Utah’s watersheds and drainage basins. Irrigators have no control over precipitation and only limited control of surface waters entering and leaving the state, as most of those are controlled by legal agreements. However, Utah’s water managers, elected officials, and water users can consider how surface water flows and groundwater storage is affected by using more efficient irrigation systems. Sprinkler, surface, or drip irrigation systems each have trade-offs in irrigation application efficiency, cost, and other factors. …


Limited Effects Of Precipitation Manipulation On Soil Respiration And Inorganic N Concentrations Across Soil Drainage Classes In Northern Minnesota Aspen Forests, Anna B. Stockstad, Robert A. Slesak, Alan J. Toczydlowski, Charles R. Blinn, Randall K. Kolka, Stephen D. Sebestyen Jul 2022

Limited Effects Of Precipitation Manipulation On Soil Respiration And Inorganic N Concentrations Across Soil Drainage Classes In Northern Minnesota Aspen Forests, Anna B. Stockstad, Robert A. Slesak, Alan J. Toczydlowski, Charles R. Blinn, Randall K. Kolka, Stephen D. Sebestyen

Aspen Bibliography

It is critical to gain insight into the responses of forest soils to the changing climate. We simulated future climate conditions with growing season throughfall reduction (by 50%) and winter snow removal using a paired-plot design across a soil drainage class gradient at three upland, Populus-dominated forests in northern Minnesota, USA. In situ bulk soil respiration and concentrations of extractable soil N were measured during the summers of 2020–2021. Soil respiration and N concentrations were not affected by throughfall reduction and snow removal, which was largely attributed to the limited treatment effects on soil moisture content and soil temperature. …


Coping With Environmental Constraints: Geographically Divergent Adaptive Evolution And Germination Plasticity In The Transcontinental Populus Tremuloides, Roos Goessen, Nathalie Isabel, Christian Wehenkel, Nathalie Pavy, Lisa Tischenko, Lyne Touchette, Isabelle Giguère, Marie-Claude Gros-Louis, Jérôme Laroche, Brian Boyle, Raju Soolanayakanahally, Karen E. Mock, Javier Hernández-Velasco, Sergio Leonel Simental-Rodriguez, Jean Bousquet, Ilga M. Porth Jul 2022

Coping With Environmental Constraints: Geographically Divergent Adaptive Evolution And Germination Plasticity In The Transcontinental Populus Tremuloides, Roos Goessen, Nathalie Isabel, Christian Wehenkel, Nathalie Pavy, Lisa Tischenko, Lyne Touchette, Isabelle Giguère, Marie-Claude Gros-Louis, Jérôme Laroche, Brian Boyle, Raju Soolanayakanahally, Karen E. Mock, Javier Hernández-Velasco, Sergio Leonel Simental-Rodriguez, Jean Bousquet, Ilga M. Porth

Aspen Bibliography

Societal Impact Statement

Syntheses clearly show that global warming is affecting ecosystems and biodiversity around the world. New methods and measures are needed to predict the climate resilience of plant species critical to ecosystem stability, to improve ecological management and to support habitat restoration and human well-being. Widespread keystone species such as aspen are important targets in the study of resilience to future climate conditions because they play a crucial role in maintaining various ecosystem functions and may contain genetic material with untapped adaptive potential. Here, we present a new framework in support of climate-resilient revegetation based on comprehensively understood …


Growing Space Management In Boreal Mixedwood Forests: 22 Year Results, Richard Kabzems, George Harper, Che Elkin Jun 2022

Growing Space Management In Boreal Mixedwood Forests: 22 Year Results, Richard Kabzems, George Harper, Che Elkin

Aspen Bibliography

Boreal mixed forests of trembling aspen (Populus tremuloides) and white spruce (Picea glauca) can provide higher outputs of many ecosystem goods and services, combined with resilience for changing environmental conditions. In this study, we examine the growth of white spruce and aspen over a range of stand compositions created by spot and broadcast treatments of broadleaves using manual and chemical means, aspen spacing, and untreated control. Twenty-two growing seasons postharvest, treatment responses created a range of broadleaf densities and spatial arrangements, reflected in significant differences in heights and diameters of the spruce mixedwood component. At this …


High Tunnel Construction Cost Calculation Workbook, Shannon Rauter, Melanie Stock, Brent Black, Dan Drost Jun 2022

High Tunnel Construction Cost Calculation Workbook, Shannon Rauter, Melanie Stock, Brent Black, Dan Drost

All Current Publications

The cost of building a high tunnel fluctuates over time with supply prices. This Excel workbook accompanies the USU Extension fact sheet, "Constructing a Low-cost High Tunnel" by Black, Drost, Rowley, and Heflebower (2011) and allows users to input local supply costs. The workbook then calculates the cost to build a USU low-cost high tunnel with several design options according to high tunnel length and door structure. It also provides an example calculation based on April 2022 pricing for reference.


Compensatory Phenolic Induction Dynamics In Aspen After Aphid Infestation, Rajarshi Kumar Gaur, Ilka Nacif De Abreu, Benedicte Riber Albrectsen Jun 2022

Compensatory Phenolic Induction Dynamics In Aspen After Aphid Infestation, Rajarshi Kumar Gaur, Ilka Nacif De Abreu, Benedicte Riber Albrectsen

Aspen Bibliography

Condensed tannins (CTs) are polyphenolics and part of the total phenolic (TP) pool that shape resistance in aspen (Populus tremula). CTs are negatively associated with pathogens, but their resistance properties against herbivores are less understood. CTs shape resistance to pathogens and chewing herbivores and could also shape resistance to aphids. Being chemical pools that are highly variable it can further be questioned whether CT-shaped resistance is better described by constitutive levels, by the induced response potential, or by both. Here, aspen genotypes were propagated and selected to represent a range of inherent abilities to produce and store foliar …


On-Farm Research Guide, Matt Yost, Jody Gale, Earl Creech, Megan Baker, Jeffrey Austin, Grant Cardon, Cody Zesiger Jun 2022

On-Farm Research Guide, Matt Yost, Jody Gale, Earl Creech, Megan Baker, Jeffrey Austin, Grant Cardon, Cody Zesiger

All Current Publications

Many growers want to increase crop productivity and farm profitability. On-farm research is a way growers can achieve this goal by discovering answers to important questions about the benefits of using specific products or practices they are uncertain about or are unproven. Validating the efficacy of already-implemented practices is another important reason to do on-farm research trials (Nielsen, 2008). Each farm is unique and can benefit from individualized on-farm research, especially since university and industry researchers cannot study every product or practice for every unique field or farm growing condition. This how-to guide covers benefits and best practices for conducting …


Nutrient Management For Recirculating Hydroponics, Noah J. Langenfeld, Lauren E. Payne, Bruce Bugbee Jun 2022

Nutrient Management For Recirculating Hydroponics, Noah J. Langenfeld, Lauren E. Payne, Bruce Bugbee

Hydroponics/Soilless Media

Steady-state nutrient management is essential in hydroponic culture. Determination of an appropriate refill solution is attained using the principle of mass balance. Optimizing the ratio of nutrient elements and refill solution concentrations requires an understanding of the ratio of nutrients in tissue to water, which is measured as water use efficiency (WUE). This ratio is then multiplied by the desired concentration of nutrients in leaf tissue to determine the refill solution composition. Deep-flow hydroponics enables constant monitoring of solution parameters and root health. We have achieved a steady-state nitrogen concentration in solution by using an automated pH control system that …


Young Forests And Fire: Using Lidar–Imagery Fusion To Explore Fuels And Burn Severity In A Subalpine Forest Reburn, Kristin H. Braziunas, Diane C. Abendroth, Monica G. Turner May 2022

Young Forests And Fire: Using Lidar–Imagery Fusion To Explore Fuels And Burn Severity In A Subalpine Forest Reburn, Kristin H. Braziunas, Diane C. Abendroth, Monica G. Turner

Aspen Bibliography

Anticipating fire behavior as climate change and fire activity accelerate is an increasingly pressing management challenge in fire-prone landscapes. In subalpine forests adapted to infrequent, stand-replacing fire, self-limitation of burn severity in short-interval fire is incompletely understood. Spatially explicit fuels data can support assessments of landscape-scale fire risk and fuel feedbacks on burn severity. For a ~1450-km2 largely forested landscape in the US Northern Rocky Mountains, we used airborne lidar and imagery to predict and map canopy and surface fuels. In a fire that burned mature (>125-year-old) and also reburned young (~30-year-old) subalpine forest, we then asked: (1) …


Ultraviolet Light-A: A Novel Agent To Dehydrate Foods, Luis J. Bastarrachea May 2022

Ultraviolet Light-A: A Novel Agent To Dehydrate Foods, Luis J. Bastarrachea

Funded Research Records

No abstract provided.


Utah Farmers Market Network: Diversity, Equity, And Inclusion Community Of Practice, Jaclyn Pace, Regan Emmons, Kelsey Hall, Celina Wille, Lacee Jimenez, Carrie Durward, Roslynn Mccann May 2022

Utah Farmers Market Network: Diversity, Equity, And Inclusion Community Of Practice, Jaclyn Pace, Regan Emmons, Kelsey Hall, Celina Wille, Lacee Jimenez, Carrie Durward, Roslynn Mccann

All Current Publications

The Utah Farmers Market Network convened a virtual Diversity, Equity, and Inclusion (DEI) Community of Practice (CoP) to explore how markets could be more welcoming and inclusive to historically excluded populations. Between May and November of 2021, members of seven Utah farmers markets convened at least twice monthly to explore basic DEI concepts and create personalized DEI strategic plans for their markets. This document reviews impacts on participants and the personal, market, community, and organizational goals created.


Utah Farmers Market Snap Toolkit, Regan Emmons, Bridget Stuchly, Gina Cornia May 2022

Utah Farmers Market Snap Toolkit, Regan Emmons, Bridget Stuchly, Gina Cornia

All Current Publications

Utah State University Extension provides research-based programs and resources with the goal of improving the lives of individuals, families and communities throughout Utah. USU Extension manages Create Better Health, Utah’s Supplemental Nutrition Assistance Education Program (known as SNAP-Ed), and provides nutrition education and obesity prevention services to SNAP recipients and other eligible low-income individuals. Create Better Health (SNAP-Ed) offers a variety of classes to expand participants’ knowledge of nutrition, budgeting, cooking, food safety, and physical activity. This toolkit outlines how farmers markets can implement a SNAP program and help combat food insecurity in their communities.


Oystershell Scale: An Invasive Threat To Aspen Conservation, Amanda M. Grady, Connor D. Crouch, Nicholas P. Wilhelmi, Richard W. Hofstetter, Kristen M. Waring May 2022

Oystershell Scale: An Invasive Threat To Aspen Conservation, Amanda M. Grady, Connor D. Crouch, Nicholas P. Wilhelmi, Richard W. Hofstetter, Kristen M. Waring

Aspen Bibliography

Aspen decline is an acute and chronic problem in Arizona, where high levels of overstory mortality and a lack of recruitment continue to be observed. Oystershell scale (Lepidosaphes ulmi; OSS), an invasive sapsucking insect, has recently become widespread in native aspen stands in the southwestern U.S., further contributing to aspen mortality. Damage is severe in lower elevation stands and within ungulate exclosures created to conserve aspen. Young recruiting aspen that are rare on the landscape incur high levels of OSS-caused mortality when infested (Fig. 1). OSS has only recently become a pest of concern in the Southwest and …