Dr. Drohan on the Signpost series Podcast in Ireland

November 18, 2023

Patrick Drohan, Professor of Soils at Penn State University, joined Mark Gibson, Head of the Teagasc Outreach & Innovation Department, on the latest podcast version of the Signpost Series to discuss catchment management initiatives in the USA.

Penn State hosts 2023 Northeast Regional Soil Judging Competition

October 1, 2023

Penn State collaborated with the Lupton Family, PA Bureau of Forestry, and State Parks to host the 2023 Northeast Regional Soil Judging Competition.

MS student Abby Owens and PhD student Jhony Benavides complete degrees!

August 31, 2023

MS student Abby Owens and PhD Student Jhony Benavides graduated in Summer 2023.

Soil Judging Team attends 2023 Nationals in Woodward, OK

May 14, 2023

The soil judging team traveled to Woodward, OK for Nationals March 26-31. About 240 students from 24 universities competed.

Penn State Soil Judging Team places 3rd at regional tourney; headed to nationals

October 26, 2022

Penn State’s student Soil Judging Team recently captured third place overall in a regional competition to qualify for the national championships next spring.

New Grant: Innovative strategies to manage Philadelphia’s soils

March 23, 2022

A team of Penn State researchers will develop recommendations and protocols for the testing and management of soils for safe production of garden and food crops in urban settings, funded by a $100,000 grant from the Pennsylvania Department of Agriculture.

MS students Emily Lesher and Sam Bayuzick graduate!

January 20, 2022

Both students accomplished an incredibly hard feat, especially given they were in graduate school during COVID.

Lab members Elka Hoelsken and Abby Owens featured in Penn State news

October 9, 2021

This past summer, Hoelsken worked as an undergraduate researcher with Abigail Owens, a graduate student in soil science. Owens is studying the effect of Penn State’s Living Filter and wastewater practices on local soil. They searched for iron concentrations and depletions in the soil and bedrock that might interrupt the supply of groundwater.

Changing cropping systems in impaired watersheds can produce water quality gains

February 9, 2021

PhD student Fei Jiang finds that growing the right crop in the right place within an impaired watershed can achieve significant water quality improvement. Jiang's research, published in Agricultural Systems, finds crop reallocation simulations resulted in a 15% reduction in total nitrogen losses, a 14% reduction in total phosphorus losses and a 39% reduction in sediment losses at an average annual scale across the watershed.

Harvesting vegetation on riparian buffers barely reduces water-quality benefits

February 9, 2021

PhD student Fei Jiang finds that allowing farmers to harvest vegetation from their riparian buffers will not significantly impede the ability of those streamside tracts to protect water quality by capturing nutrients and sediment -- and it will boost farmers' willingness to establish buffers. Jiang's research is published in the Journal of Environmental Quality.

PARN Developed and Serving Pennsylvania

September 1, 2020

The goal of PARN is to rapidly scale-up an open source platform that connects producers, suppliers, manufacturers, and workers along PA’s food supply chain, thus minimizing bottlenecks. Our platform can reach a diverse group of stakeholders to provide urgently needed support now, while also building infrastructure for a more resilient regional food economy over the long term.

COVID-19 Idea for US States: State Agriculture Assessment Team Risk Planning

March 26, 2020

Our lab group knows of no current issues with the Agricultural supply chain in the USA and COVID-19 disruptions. However, the potential trend of "soon overwhelmed health systems" has us concerned. What we are most concerned about is a fragile demographic (farming now) and the risk of C19 further disrupting it and creating a negative economic feedback. Around the USA, Land Grants could take a lead in developing Agriculture Assessment Planning Teams but state committee membership should not be limited to College of Ag members. There are likely people in Business programs, other academic departments, and outside University entities, who all could be helpful to have on such a committee. For example, are their retired military experts in logistics planning who could be members? We are currently working with others to support development of a support network for farmers.

NEW PAPER: Soil Chemistry, and Not Short-term (1-2 year) Deer Exclusion, Explains Understory Plant Occupancy in Forests Affected by Acid Deposition

October 23, 2019

Danielle R Begley-Miller, Duane R Diefenbach, Marc E McDill, Patrick J Drohan, Christopher S Rosenberry, Emily H Just Domoto. In AoB PLANTS: The loss of species diversity and plant community structure throughout the temperate deciduous forests of North America have often been attributed to overbrowsing by white-tailed deer (Odocoileus virginanus). Slow species recovery following removal from browsing, or reduction in deer density, has been termed a legacy effect of past deer herbivory. However, vegetation legacy effects have also coincided with changes to soil chemistry throughout the north-eastern USA. In this paper, we assess the viability of soil chemistry (i.e. pH, extractable nutrients and extractable metals) and other factors (topography, light, overstory basal area and location) as alternative explanations for a lack of vegetation recovery. We compared the relative effects of soil chemistry, site conditions and short-term (1–2 year) deer exclusion on single-species occupancy probabilities of 10 plant taxa common to oak-hickory forests in central Pennsylvania. We found detection for all modelled species was constant and high (⁠p^ > 0.65), and occupancy probability of most taxa was best explained by at least one soil chemistry parameter. Specifically, ericaceous competing vegetation was more likely to occupy acidic (pH < 3.5), base cation-poor (K < 0.20 cmolc kg−1) sites, while deer-preferred plants were less likely to occur when soil manganese exceeded 0.1 cmolc kg−1. Short-term deer exclusion did not explain occupancy of any plant taxon, and site conditions were of nominal importance. This study demonstrates the importance of soil chemistry in shaping plant community composition in the north-central Appalachians, and suggests soil as an alternative, or additional, explanation for deer vegetation legacy effects. We suggest that the reliance on phyto-indicators of deer browsing effects may overestimate the effects of browsing if those species are also limited by unfavourable soil conditions. Future research should consider study designs that address the complexity of deer forest interactions, especially in areas with complex site-vegetation histories.

Lab Fulbright Scholar Jhony Benevides presents thesis work at Colombian Fulbright event

August 27, 2019

MS student Jhony Benevides was one of 4 Penn State Fulbright Scholars affiliated with the Cacao for Peace program to present at a Colombian Fulbright sponsored Cátedra in Monteria, Colombia.

New Paper: A Global Perspective on the History of Phosphorus Management Decision Support Approaches in Agriculture: Lessons Learned and Directions for the Future

July 15, 2019

Our new Journal of Environmental Quality paper on the the evolution of phosphorus (P) management decision support tools (DSTs) and systems (DSS) is out!

Cocoa, Colombia and Dogs

March 28, 2019

Canine team suelo helps advance cocoa research in Colombia

NEW BOOK CHAPTER: Backyard portals: A solutions-oriented approach to understanding and valuing soil.

March 11, 2019

Pennsylvania artist Stacy Levy and Penn State soil scientist Patrick Drohan teamed up to address the question...."How can we value nature through artistic and scientific methodologies?"...click to read more.

NEW PAPER: Geochemical and mineralogical characteristics of loess along northern Appalachian, USA major river systems appear driven by differences in meltwater source lithology

March 11, 2019

K.S. Lindeburg and P.J. Drohan: Eastern United States loess mapped by the U.S. Department of Agriculture, National Resources Conservation Service (USDA-NRCS) mostly occurs near major river systems like the Delaware and Susquehanna Rivers. Results suggest that developing a “loess fingerprint” for each river system based on major, minor and rare earth elements is possible, and likely to be useful in differentiating sources; however coarse silts may be a more effective fraction (than fine silts) for sediment sourcing, especially if rare earth elements are used.

NPR, State Impact covers our shale-gas reclamation research with PADCNR, Bureau of Forestry

September 11, 2018

The Mock Pad Project is a collaborative effort between the Pennsylvania Bureau of Forestry and Penn State to demonstrate how shale-gas development, and similar forest disturbances, can be reclaimed.

SOILS 499A/B heads to Wexford, Ireland

June 11, 2018

Dr. Drohan's course on the co-evolution of soil and civilization visited Wexford, Ireland this May for its embedded course component.

SOILS 404 educates Philadelphia students about SOILS!

April 25, 2018

Dr. Patrick Drohan and Dr. Heather Gall received a grant (the Harbaugh faculty scholar award) from the College of Agriculture at Penn State to collaborate on urban green infrastructure education via their classes. As part of this grant's activities, Dr. Drohan's SOILS 404 (Urban Soils) class visited Greenfield Elementary School this past week to speak to 5th graders about soil and why it matters to people in cities.

Lab Member Nico Navarro's World Soils Day podcast

February 23, 2018

Lab member Nico Navarro shared his story about soils and why he thinks they are important enough to study for his Master's Degree in Soil Science. We are proud to have him working in our lab at Penn State!

New Paper: Weathering of rock to regolith: The activity of deep roots in bedrock fractures

December 6, 2017

Many areas in the world are characterized by shallow soils underlain by weathered bedrock, but root-rock interactions and their implications for regolith weathering are poorly understood. To test the role of tree roots in weathering bedrock, we excavated four pits along a catena in a shale-dominated catchment at the Susquehanna Shale Hills Critical Zone Observatory (SSHCZO) in central Pennsylvania.

New Paper: Unconventional gas development facilitates plant invasions

July 25, 2017

Vegetation removal and soil disturbance from natural resource development, combined with invasive plant propagule pressure, can increase vulnerability to plant invasions. Unconventional oil and gas development produces surface disturbance by way of well pad, road, and pipeline construction, and increased traffic.

NEW PAPER: Short-term Forecasting Tools for Agricultural Nutrient Management

May 9, 2017

The advent of real-time, short-term farm management tools is motivated by the need to protect water quality above and beyond the general guidance offered by existing nutrient management plans. Advances in high-performance computing and hydrologic or climate modeling have enabled rapid dissemination of real-time information that can assist landowners and conservation personnel with short-term management planning. This paper reviews short-term decision support tools for agriculture that are under various stages of development and implementation in the United States: (i) Wisconsin’s Runoff Risk Advisory Forecast (RRAF) System, (ii) New York’s Hydrologically Sensitive Area Prediction Tool, (iii) Virginia’s Saturated Area Forecast Model, (iv) Pennsylvania’s Fertilizer Forecaster, (v) Washington’s Application Risk Management (ARM) System, and (vi) Missouri’s Design Storm Notification System. Although these decision support tools differ in their underlying model structure, the resolution at which they are applied, and the hydroclimates to which they are relevant, all provide forecasts (range 24–120 h) of runoff risk or soil moisture saturation derived from National Weather Service Forecast models. Although this review highlights the need for further development of robust and well-supported short-term nutrient management tools, their potential for adoption and ultimate utility requires an understanding of the appropriate context of application, the strategic and operational needs of managers, access to weather forecasts, scales of application (e.g., regional vs. field level), data requirements, and outreach communication structure.

Our research makes the news: Shale gas threat to forests can be eased by consolidating infrastructure

April 19, 2017

By Jeff Mulhollem April 19, 2017 .. .. UNIVERSITY PARK, Pa. — Fragmentation of ecologically important core forests within the northern Appalachians — driven by pipeline and access road construction — is the major threat posed by shale-gas development, according to researchers, who recommend a change in infrastructure-siting policies to head off loss of this critical habitat.

New Paper: Linear infrastructure drives habitat conversion and forest fragmentation associated with Marcellus shale gas development in a forested landscape

April 3, 2017

Highlights: Pipelines comprised the largest portion of the shale gas industry footprint; Pipelines were the largest contributor to the fragmentation of core forest; Loss of core forest was double on private land compared to public land; Methods to consolidate pipelines with other infrastructure should be used; New pads should be placed near existing pipelines to reduce further fragmentation.

New Book Chapter: Soils of the United States

March 22, 2017

This new book chapter highlights the unique characteristics of soils across the United States and discusses their genesis. The chapter is part of a new International Encyclopedia of Geography.

New Paper: Simulating ungulate herbivory across forest landscapes: A browsing extension for LANDIS-II

February 23, 2017

Highlights • We developed a Browse Extension to simulate effects of ungulates on the growth and survival of plant species cohorts. • The capabilities of the extension were explored via case studies in the Allegheny National Forest and Isle Royale National Park, USA. • In both model applications, browsing reduced total aboveground live biomass and caused shifts in forest composition. • Simulations that included effects of browsing resulted in successional patterns that were similar to those observed in the study regions. • Neglecting effects of browsing when modeling forest succession may result in flawed predictions of forest biomass and composition in some ecosystems.

NEW PAPER: Provisional, Forested Ecological Sites in the Northern Appalachians and Their State-and-Transition Models

January 4, 2017

The identification of unique areas of vegetative potential across the Northern Appalachians is complicated by a long land-use history of vegetation management. We introduce provisional ecological sites and associated state-and-transition models for the region, which can be differentiated by latitudinal drivers of: precipitation and temperature; local parent material and resulting soil differences; and landscape position, slope, or aspect. Identification of ecological sites and associated States or Phases in the Northern Appalachians provides land managers with quantifiable benchmarks for assessing forest compositional shifts due to natural or anthropogenic disturbance. Drohan, Patrick, and Alex Ireland. "Provisional, Forested Ecological Sites in the Northern Appalachians and Their State-and-Transition Models." Rangelands (2016).