About

Our faculty are engaged and dedicated educators, advisors, and mentors and have been honored with numerous university-wide and national teaching awards. Our classes emphasize the latest research coupled with cutting-edge technology and practices making our graduates among the most competitive candidates in the country for natural resource professions. Our curricula include everything from protected lands management and urban forestry, to industrial forestry operations and ecology. Small class sizes and faculty dedicated to teaching afford students the chance to get to know their professors personally. Wide varieties of academic and professional opportunities are available through research, student organizations, and public outreach programs organized by the faculty.

Research topics

• Biology
• Ecology
• Environmental science
• Soil science
• Geology
• Botany
• Geography
• Agronomy
• Chemistry
• Cartography
• Mathematics
• Horticulture
• Statistics
• Environmental chemistry

Selected publications

• Corrigendum to “Detecting change in belowground carbon stocks: Statistical feasibility and future opportunities from loblolly pine forests” [For. Ecol. Manag. 595 (2025) 122970]

  Forest Ecology and Management · 2025-10-18

  erratumSenior author
  PublisherDOI

• Spatial Decoupling of Biological and Geochemical Phosphorus Cycling in Podzolized Soils

  Soil Systems · 2025-10-16 · 1 citations

  articleOpen access

  Phosphorus (P) is essential to life yet constrained by finite reserves, heterogeneous distribution, and strong chemical binding to soil minerals. Pedogenesis progressively alters the availability of P: in ‘young’ soils, P associated with Ca and Mg is relatively labile, while in ‘old’ soils, acidification and leaching deplete base cations, shifting P into organic matter and recalcitrant Al- and Fe-bound pools. Podzolized soils (Spodosols) provide a unique lens for studying this transition because podzolization vertically segregates these dynamics into distinct horizons. Organic cycling dominates the surface horizon, while downward translocation of Al, Fe, and humus creates a spodic horizon that immobilizes P through sorption and co-precipitation in amorphous organometal complexes. This spatial separation establishes two contrasting P pools—biologically dynamic surface P and mineral-stabilized deep P—that may be variably accessible to plants and microbes depending on depth, chemistry, and hydrology. We synthesize mechanisms of spodic P retention and liberation, including redox oscillations, ligand exchange, root exudation, and physical disturbance, and contrast these with strictly mineral-driven or biologically dominated systems. We further propose that podzols serve as natural experimental models for ecosystem aging, allowing researchers to explore how P cycling reorganizes as soils develop, how vertical stratification structures biotic strategies for nutrient acquisition, and how deep legacy P pools may be remobilized under environmental change. By framing podzols as a spatial analogue of long-term weathering, this paper identifies them as critical systems for advancing our understanding of nutrient limitation, biogeochemical cycling, and sustainable management of P in diverse ecosystems.

  PublisherOA PDFDOI

• Loblolly Pine Growth and Competition Response to Varied Chemical Site Preparation and Release Treatments 14 Years After Establishment in the Piedmont of Virginia

  Journal of Forestry · 2025-01-01

  articleOpen access

  Abstract We examined the 14-year effects of experimentally varied chemical site preparation and release treatments in a Pinus taeda L. plantation in Dillwyn, Virginia, US. The study examined the effects of timing (July, September, or October) for imazapyr site preparation, with or without the addition of sulfometuron methyl (SFM), year-one release from herbaceous weeds using SFM plus imazapyr, and year-two release treatment using imazapyr at a rate to control hardwoods. Chemical site preparation treatment applications exhibited a reduction in competition basal area ha -1 and an increase in pine volume compared to the check, however, application timing was the most influential factor in determining the effectiveness of the treatments. September 3rd and October 1st applications averaged less competing vegetation basal area than the year-two release and the check plots. At age 14-years, competing vegetation reduced individual pine tree volumes by 5.6% for every one m 2 of competing vegetation basal area.

  PublisherOA PDFDOI

• A regional coastal Douglas-fir index of site quality for young stands in western Washington, USA

  Forest Ecology and Management · 2025-08-12

  articleSenior author
  PublisherDOI

• Detecting change in belowground carbon stocks: Statistical feasibility and future opportunities from loblolly pine forests

  Forest Ecology and Management · 2025-07-19 · 1 citations

  articleSenior author
  PublisherDOI

• Lifting the profile of deep soil carbon in New Zealand’s managed planted forests

  Carbon Balance and Management · 2025-08-14

  articleOpen access

  BACKGROUND: Forest soils are a globally significant carbon-store, including in deep layers (> 30 cm depth). However, there is high uncertainty regarding the response of deep soil organic carbon (DSOC) to climate change and the resulting impact on the total OC budget for forest ecosystems. Managed forests have an opportunity to reduce the risk of DSOC loss with climate change, however, the basic understanding of DSOC is lacking. Planted forests in New Zealand are managed with very limited knowledge of DSOC, both in the amount and the capacity of the soil to continue to store carbon with climate change. In this study, we explore DSOC stocks to at least 2 m depth at 15 planted forest sties in New Zealand. We also explore DSOC radiocarbon age and soil mineralogy, then contextualise our results within international SOC datasets and climate change vulnerability frameworks to identify research priorities for New Zealand's planted forest soils. RESULTS: DSOC stocks and soil mineralogy in New Zealand's planted forests were diverse both horizontally across soil types and vertically throughout the soil profile. Critically, limiting measurements of SOC to the top 30 cm misses more than half of the SOC stocks present to at least 2 m depth (mean 57%; range 33-72%). At depth, mineral-associated OC was the dominant fraction of DSOC (average > 90%) and was on average much older (> 1000 years) than the current planted forest land use (< 100 years). CONCLUSIONS: This small case study highlights that New Zealand's planted forests contain substantial stocks of DSOC, much of which is older than the current forest land use. The deep soils were dominated by reactive metals, and although the age of DSOC suggest long-term stability, the large contribution of reactive metal-mediated SOC stabilisation may indicate vulnerability to warming soil temperatures relative to other climate change factors. There is a pressing need to expand soil sampling to greater depths and establish a robust SOC baseline for New Zealand's planted forests. This is essential for enabling spatial predictions of DSOC dynamics under future climate scenarios, identify the key controls on DSOC persistence, and concomitant impacts on forest ecosystem function and resilience.

  PublisherOA PDFDOI

• Assessing the effects of plant species, functional traits, and groups on soil microbial diversity

  Applied Soil Ecology · 2025-08-21 · 6 citations

  article
  PublisherDOI

• Assessing the Effects of Plant Species, Functional Traits and Groups on Soil Microbial Diversity

  SSRN Electronic Journal · 2025-01-01

  preprintOpen access
  PublisherDOI

• Tadpole aggregations create biogeochemical hotspots in wetland ecosystems

  Journal of Animal Ecology · 2024-11-17 · 1 citations

  articleOpen access

  Abstract Animal waste can contribute substantially to nutrient cycling and ecosystem productivity in many environments. However, little is known of the biogeochemical impact of animal excretion in wetland habitats. Here we investigate the effects of wood frog ( Lithobates sylvaticus ) tadpole aggregations on nutrient recycling, microbial metabolism and carbon cycling in geographically isolated wetlands. We used a paired mesocosm and field study approach that utilized measurements of tadpole excretion rates, microbial extracellular enzyme activities, and litter degradation. We found a strong relationship between tadpole development and nutrient excretion, demonstrating that ontological changes impact tadpole‐mediated nutrient cycling in wetland habitats. Further, the interplay between population‐level tadpole excretion and wetland hydrologic conditions increased ambient and concentrations by 56 and 14 times, respectively, compared to adjacent wetlands without tadpoles. Within our mesocosm study, microbes decreased extracellular enzyme production associated with nitrogen acquisition in response to the presence of tadpole‐derived nitrogen. In addition to microbial metabolic responses, tadpole presence enhanced litter breakdown in both mesocosms and wetlands by 7% and 12%, respectively, in comparison to reference conditions. These results provide evidence for the functional and biogeochemical role of tadpole aggregations in wetland habitats, with important implications for ecosystem processes, biodiversity conservation, and ecosystem management.

  PublisherOA PDFDOI

• Fungal biomass and ectomycorrhizal community assessment of phosphorus responsive Pinus taeda plantations

  Frontiers in Fungal Biology · 2024-05-28

  articleOpen access

  Ectomycorrhizal fungi and non-ectomycorrhizal fungi are responsive to changes in environmental and nutrient availabilities. Although many species of ectomycorrhizas are known to enhance the uptake of phosphorus and other nutrients for Pinus taeda , it is not understood how to optimize these communities to have tangible effects on plantation silviculture and P use efficiency. The first step of this process is the identification of native fungi present in the system that are associated with P. taeda and influence P uptake efficiency. We used sand-filled mesh bags baited with finely ground apatite to sample ectomycorrhizal and non-ectomycorrhizal fungi associated with the rhizosphere of P-responsive P. taeda under several field conditions. Mesh bags were assessed for biomass accumulation over three years using a single three-month burial period pre-harvest and three six-month burial periods post-planting. Amplicon sequencing assessed ectomycorrhizal and non-ectomycorrhizal communities between phosphorus treatments, sites, mesh bags, and the rhizosphere of actively growing P. taeda in the field. We found biomass accumulation within the mesh bags was inversely related to increasing phosphorus fertilization (carryover) rates from pre-harvest to post-planting. Up to 25% increases in total biomass within the bags were observed for bags baited with P. Taxonomic richness was highest in Alfisol soils treated with phosphorus from the previous rotation and lowest in the Spodosol regardless of phosphorus treatment.

  PublisherOA PDFDOI

Recent grants

• Determining how Organic Matter is Stabilized using a Unique Set of Soil Samples from across the U.S.

  NSF · $732k · 2014–2021

Frequent coauthors

• Michael SanClements

  National Ecological Observatory Network

  32 shared

• L. E. Nave

  Michigan Technological University

  22 shared

• John R. Seiler

  22 shared

• Timothy B. Harrington

  20 shared

• Robert A. Slesak

  Pacific Northwest Research Station

  19 shared

• J. A. Hatten

  Oregon State University

  18 shared

• Stephen H. Schoenholtz

  Virginia Tech

  18 shared

• Katherine Heckman

  Northern Research Station

  15 shared