Botany Commons^™

Public Horticulture: Process And Design Of The Lincoln Botanical Garden, Brad Kindler

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

Beginning in 2012, the local non-profit, The Lincoln Botanical Garden, began organizing the conceptual design and creation of a glass conservatory within a botanical garden in Lincoln, Nebraska. These proposed urban enhancements seek to fill a gap in garden amenities in the city by providing year-round access to public horticulture programming and education.

This project, Public Horticulture: Process and Design of the Lincoln Botanical Garden, documents these efforts and makes design recommendations for a themed Glacial Erratic Garden that could be constructed within the botanical garden.

Advisors: Ellen Paparozzi and Sam Wortman

Overexpression Of Msdreb1c Modulates Growth And Improves Forage Quality In Tetraploid Alfalfa (Medicago Sativa L.), Yangyang Zhang, Zhen Wang, Fan Zhang, Xue Wang, Yajing Li, Ruicai Long, Mingna Li, Xianyang Li, Quanzhen Wang, Qingchuan Yang, Junmei Kang

Department of Agronomy and Horticulture: Faculty Publications

DREB has been reported to be involved in plant growth and response to environmental factors. However, the function of DREB in growth and development has not been elucidated in alfalfa (Medicago sativa L.), a perennial tetraploid forage cultivated worldwide. In this study, an ortholog of MtDREB1C was characterized from alfalfa and named MsDREB1C accordingly. MsDREB1C was significantly induced by abiotic stress. The transcription factor MsDREB1C resided in the nucleus and had self-transactivation activity. The MsDREB1C overexpression (OE) alfalfa displayed growth retardation under both long-day and short-day conditions, which was supported by decreased MsGA20ox and upregulated MsGA2ox in the OE …

Evaluating Consistency Across Multiple Neospectra (Compact Fourier Transform Near-Infrared) Spectrometers For Estimating Common Soil Properties, Sadia M. Mitu, Colleen Smith, Jonathan Sanderman, Richard R. Ferguson, Keith Shepherd, Yufeng Ge

Department of Agronomy and Horticulture: Faculty Publications

Rapid and cost-effective techniques for soil analysis are essential to guide sustainable land management and production agriculture. This study aimed at evaluating the performance and consistency of portable handheld Fourier-transform near-infrared spectrometers and the NeoSpectra scanners in estimating 12 common soil physical and chemical properties including pH; organic carbon (OC); inorganic carbon (IC); total nitrogen (TN); cation exchange capacity (CEC); clay, silt, and sand fractions; and exchangeable potassium (K), phosphorus (P), calcium (Ca), and magnesium (Mg). A diverse set of samples (n = 600) were retrieved from a national-scale soil archive of the Kellogg Soil Survey Laboratory of USDA-NRCS …

Accurate Measurement Of Field Size Is Essential For Analysis Of Smallholder Survey Data, Rica Joy Flor, Shen Yuan, Gonzalo Rizzo, Fahmuddin Agus, Anny Ruth P. Pame, Akhara Ouk, Rathmuny Then, Sokheng Keo, Virender Kumar, Particio Grassini

Department of Agronomy and Horticulture: Faculty Publications

Context: Agronomic surveys play a vital role in identifying on-farm yield constraints and opportunities to increase productivity, input-use efficiency, and farmer profit. These surveys typically rely on farmer-reported data, where crop yield and applied inputs per hectare are estimated based on farmer-reported total harvested output and applied inputs per field and associated field size. At question is how accurate field size is, which is vital in the case of smallholders as small inaccuracies can lead to large biases in estimated yield and inputs.

Objectives: The goals of this study are to assess current approaches to determine field size …

Phenotypic Diversity For Morpho-Agronomic Traits In The Us Proso Millet (Panicum Miliaceum L.) Core Collection, Santosh G. Rajput, Rituraj Khound, Dipak K. Santra

Department of Agronomy and Horticulture: Faculty Publications

Proso millet (Panicum miliaceum L.) is a short-season annual crop known for high water-use efficiency and drought tolerance. The low water requirement makes this ancient grain an excellent rotational crop for the winter wheat-based dryland cropping system in theHigh Plains of theUnited States. The genetic base of the commonly grown US cultivars is very narrow. Assessment of proso millet germplasm for agronomic traits is essential for its efficient utilization in the genetic improvement of this crop. The objectives of this study were to (1) characterize the US proso millet germplasm based on nine important morpho-agronomic traits and (2) classify …

Examination Of Greenhouse Conditions That Influence Scale Infestation Rates On Begonia, Madeline M. Cusick

Honors College Theses

Scale insects are common pests within greenhouse and agricultural settings. I quantified scale infestation on Begonia x Richmondensis, also known as the Dragon Wing begonia, within the Armstrong Campus Greenhouse from March to November of 2023. Six different treatments accounted for variations in sunlight, humidity, and temperature within the greenhouse with the goal of determining the insect’s preferred environmental conditions. Morphological comparisons were also made between host plant Dragon Wing begonia and other begonias present within the greenhouse. Analysis indicated a significant difference in scale presence on replicate plants by zone and sunlight treatments, with more plants hosting at least …

Soil Health Cycle, Bijesh Maharjan, Saurav Das, Vesh R. Thapa, Bharat Sharma Acharya

Department of Agronomy and Horticulture: Faculty Publications

Soil health is pivotal to agricultural sustainability. Promoting and sustaining soil health management is challenging since it involves many interdependent components and steps and is an iterative process. Herein, the soil health cycle (SHC) is proposed as a soil health management cycle encompassing human dimensions, management practices, and their effects on soil health indicators (SHIs), leading to subsequent impacts on soil functions. The SHC provides a structure for an iterative testing of changes to improve soil health. A systematic review of research publications was also conducted using the Web of Science database supplemented by Elicit AI and Scopus API searches …

Providing Pest Management Education For Home Gardeners In Utah, Nick Volesky, Marion Murray

Outcomes and Impact Quarterly

In January 2024, Utah State University (USU) Extension's Integrated Pest Management (IPM) program launched a three-part class series targeting Utah's home gardeners. The goal was to enhance their abilities in identifying and managing insect and plant diseases. With over 200 participants, the series notably increased the knowledge of attendees. This initiative aligns with the USU Extension IPM program's mission to promote sustainable pest management practices across Utah, evidencing its commitment to environmental stewardship and community education.

Toward A Coordinated Understanding Of Hydro-Biogeochemical Root Functions In Tropical Forests For Application In Vegetation Models, Daniela F. Cusack, Bradley O. Christoffersen, Chris M. Smith-Martin, Kelly M. Andersen, Amanda L. Cordeiro, Katrin Fleischer, S. Joseph Wright, Nathaly R. Guerrero-Ramírez, Laynara F. Lugli, Lindsay A. Mcculloch

School of Integrative Biological & Chemical Sciences Faculty Publications

Tropical forest root characteristics and resource acquisition strategies are underrepresented in vegetation and global models, hampering the prediction of forest–climate feedbacks for these carbon-rich ecosystems. Lowland tropical forests often have globally unique combinations of high taxonomic and functional biodiversity, rainfall seasonality, and strongly weathered infertile soils, giving rise to distinct patterns in root traits and functions compared with higher latitude ecosystems. We provide a roadmap for integrating recent advances in our understanding of tropical forest belowground function into vegetation models, focusing on water and nutrient acquisition. We offer comparisons of recent advances in empirical and model understanding of root characteristics …

Interacting Effects Of Nutrient Availability And Environmental Change On Grassland Plant Communities, George Robert Wheeler

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The availability of nutrients plays an important role in shaping the composition, productivity and diversity of plant communities. Such effects are particularly well documented in grassland ecosystems, where both independent studies and collaborations such as the Nutrient Network consistently show increasing productivity and decreasing diversity with the addition of limiting nutrients. The specifics of this pattern, however, vary widely from site to site, and within a single site, they may shift with changes in environmental conditions and disturbance regimes.

My research at Cedar Creek Ecosystem Science Reserve (Minnesota, USA), documents such a pattern through resampling of a long-term experiment on …

2024 Woy: Turtleheads And Bumblebees, W. John Hayden

Biology Faculty Publications

No abstract provided.

Long-Term Soil Change In The Us Great Plains: An Evaluation Of The Haas Soil Archive, Mark A. Liebig, Francisco J. Calderon, Andrea K. Clemensen, Lisa Durso, Jessica L. Duttenhefner, Jed O. Eberly, Jonathan J. Halvorson, Virginia L. Jin, Kyle Mankin, Andrew J. Margenot, Catherine E. Stewart, Scott Van Pelt, Merle F. Vigil

Department of Agronomy and Horticulture: Faculty Publications

Diverse patterns of climate and edaphic factors challenge detection of soil property change in the US Great Plains. Because detectable soil change can take decades, insights into the trajectory of soil properties frequently require long-term site monitoring and, where available, associated soil archives to enable comparisons with initial or baseline states. Unfortunately, few multi-decadal soil change investigations have been conducted in this region. Here, we document effects of dryland cropping on a suite of soil properties by comparing matched historic (1947) and contemporary (2018) soil samples from the Haas Soil Archive at three sites in the US Great Plains: Moccasin, …

Imitating The “Breeder’S Eye”: Predicting Grain Yield From Measurements Of Non-Yield Traits, Hongyu Jin, Michael C. Tross, Ruijuan Tan, Linsey Newton, Ravi V. Mural, Jinliang Yang, Addie M. Thompson, James C. Schnable

Department of Agronomy and Horticulture: Faculty Publications

Plant breeding relies on information gathered from field trials to select promising new crop varieties for release to farmers and to develop genomic prediction models that can enhance the efficiency of genetic improvement in future breeding cycles. However, generating the genetic marker data required to apply genomic prediction at the early stages of a breeding program remains costly for many public-sector breeding programs as well as for many plant breeders operating in developing countries. As the pace of climate change intensifies, the time lag of developing and deploying new crop varieties requires plant breeders to make selection decisions without knowing …

Pollen-Mediated Gene Flow From Herbicide-Resistant Yellow Corn To Non-Genetically Engineered Food-Grade White Corn, Mandeep Singh, Vipan Kumar, Stevan Z. Knezevic, John L. Lindquist, Suat Irmak, Santosh Pitla, Amit J. Jhala

Department of Agronomy and Horticulture: Faculty Publications

Nebraska is the number one producer of food-grade white corn in the United States. Pollen-mediated gene flow (PMGF) from genetically engineered high alpha-amylase corn, known as Enogen corn, to food-grade white corn can have undesirable outcomes. Alpha-amylase can convert starch in white corn to sugar during or after its processing, degrading the quality of processed products. Thus, proximity to Enogen corn puts white corn production at risk. The objectives of this study were to evaluate the PMGF from herbicide-resistant yellow corn to food-grade white corn and assess the significance of wind speed and direction. Field experiments were set up using …

Leveraging Digital Agriculture For On-Farm Testing Of Technologies, Laila A. Puntel, Laura J. Thompson, Taro Mieno

Department of Agronomy and Horticulture: Faculty Publications

The Precision Nitrogen Project (PNP) worked with more than 80 corn and winter wheat producers to inexpensively design and implement randomized, replicated field strip trials on whole commercial farm fields, and to provide site-specific testing of current nitrogen (N) technologies. This article proposes a conceptual framework and detailed procedure to select the N technology to be tested; design and implement field trials; generate, process, and manage field trial data; and automatically analyze, report, and share benefits from precision N technology. The selection of the N technology was farmer-driven to ensure a good fit and to increase the likelihood of future …

Variation In Leaf Chlorophyll Concentration In Response To Nitrogen Application Across Maize Hybrids In Contrasting Environments, Kyle M. Linders, Dipak K. Santra, James C. Schnable, Brandi Sigmon

Department of Agronomy and Horticulture: Faculty Publications

Leaf chlorophyll concentration was measured for 84 publicly available maize hybrids grown under three nitrogen fertilizer treatments in two contrasting environments in Nebraska. The effect of nitrogen treatment on chlorophyll response was found to be significant (p < 0.05) for both locations. In Scottsbluff, chlorophyll concentrations increased significantly with increasing nitrogen rate, while no significant difference was found between medium and high nitrogen in Lincoln. Within equivalent nitrogen treatments, chlorophyll was more abundant in Lincoln than Scottsbluff for nearly every hybrid. Hybrid response was not consistent between environments, with approximately 11% of variance explained by genotype by environment interaction.

Calibration Of Hybrid-Maize Model For Simulation Of Soil Moisture And Yield In Production Corn Fields, Anthony A. Amori, Olufemi P. Abimbola, Trenton E. Franz, Daran Rudnick, Javed Iqbal, Haishun Yang

Department of Agronomy and Horticulture: Faculty Publications

Model calibration is essential for acceptable model performance and applications. The Hybrid-Maize model, developed at the University of Nebraska-Lincoln, is a process-based crop simulation model that simulates maize growth as a function of crop and field management and environmental conditions. In this study, we calibrated and validated the Hybrid-Maize model using soil moisture and yield data from eight commercial production fields in two years. We used a new method for the calibration and multi-parameter optimization (MPO) based on kriging with modified criteria for selecting the parameter combinations. The soil moisture-related parameter combination (SM-PC3) improved simulations of soil water dynamics, but …

Toward A Coordinated Understanding Of Hydro-Biogeochemical Root Functions In Tropical Forests For Application In Vegetation Models, Daniela F. Cusack, Bradley Christoffersen, Chris M. Smith-Martin, Kelly M. Andersen, Amanda L. Cordeiro, Katrin Fleischer, S. Joseph Wright, Nathaly R. Guerrero-Ramírez, Laynara F. Lugli, Lindsay A. Mcculloch, Mareli Sanchez-Julia, Sarah A. Batterman, Caroline Dallstream, Claire Fortunel, Laura Toro, Lucia Fuchslueger, Michelle Y. Wong, Daniela Yaffar, Joshua B. Fisher, Marie Arnaud, Lee H. Dietterich, Shalom D. Addo-Danso, Oscar J. Valverde-Barrantes, Monique Weemstra, Jing Cheng Ng, Richard J. Norby

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Tropical forest root characteristics and resource acquisition strategies are underrepresented in vegetation and global models, hampering the prediction of forest–climate feedbacks for these carbon-rich ecosystems. Lowland tropical forests often have globally unique combinations of high taxonomic and functional biodiversity, rainfall seasonality, and strongly weathered infertile soils, giving rise to distinct patterns in root traits and functions compared with higher latitude ecosystems. We provide a roadmap for integrating recent advances in our understanding of tropical forest belowground function into vegetation models, focusing on water and nutrient acquisition. We offer comparisons of recent advances in empirical and model understanding of root characteristics …

U.S. Cereal Rye Winter Cover Crop Growth Database, Alexandra M. Huddell, Resham Thapa, Guillermo S. Marcillo, Lori J. Abendroth, Victoria J. Ackroyd, Shalamar D. Armstrong, Gautam Asmita, Muthukumar V. Bagavathiannan, Kipling S. Balkcom, Andrea Basche, Shawn Beam, Kevin Bradley, Lucas Pecci Canisares, Heather Darby, Adam S. Davis, Pratap Devkota, Warren A. Dick, Jeffery A. Evans, Wesley J. Everman, Tauana Ferreira De A Lmeida, Michael L. Flessner, Lisa M. Fultz, Stefan Gailans, Masoud Hashemi, Joseph Haymaker, Matthew J. Helmers, Nicholas Jordan, Thomas C. Kaspar, Quirine M. Ketterings, Eileen Kladivko, Alexandra Kravchenko, Eugene P. Law, Lauren Lazaro, Ramon G. Leon, Jeffrey Liebert, John Lindquist, Kristen Loria, Jodie M. Mcvane, Jarrod O. Miller, Michael J. Mulvaney, Nsalambi V. Nkongolo, Jason K. Norsworthy, Binaya Parajuli, Christopher Pelzer, Cara Peterson, Hanna Poffenbarger, Pratima Poudel, Mark S. Reiter, Matt Ruark, Matthew R. Ryan, Spencer Samuelson, John E. Sawyer, Sarah Seehaver, Lovreet S. Shergill, Yogendra Raj Upadhyaya, Mark Vangessel, Ashley L. Waggoner, John M. Wallace, Samantha Wells, Charles White, Bethany Wolters, Alex Woodley, Rongzhong Ye, Eric Youngerman, Brian A. Needelman, Steven B. Mirsky

Department of Agronomy and Horticulture: Faculty Publications

Winter cover crop performance metrics (i.e., vegetative biomass quantity and quality) affect ecosystem services provisions, but they vary widely due to differences in agronomic practices, soil properties, and climate. Cereal rye (Secale cereale) is the most common winter cover crop in the United States due to its winter hardiness, low seed cost, and high biomass production. We compiled data on cereal rye winter cover crop performance metrics, agronomic practices, and soil properties across the eastern half of the United States. The dataset includes a total of 5,695 cereal rye biomass observations across 208 site-years between 2001–2022 and encompasses …

Intensifying Rice Production To Reduce Imports And Land Conversion In Africa, Shen Yuan, Kazuki Saito, Pepijn A.J. Van Oort, Martin K. Van Ittersum, Shaobing Peng, Patricio Grassini

Department of Agronomy and Horticulture: Faculty Publications

Africa produces around 60% of the rice the continent consumes, relying heavily on rice imports to fulfill the rest of the domestic demand.Over the past 10 years, the rice-agricultural area increased nearly 40%, while average yield remained stagnant. Here we used a process-based crop simulation modelling approach combined with local weather, soil, and management datasets to evaluate the potential to increase rice production on existing cropland area in Africa and assess cropland expansion and rice imports by year 2050 for different scenarios of yield intensification. We find that Africa can avoid further increases in rice imports, and even reduce them, …

Filling The Agronomic Data Gap Through A Minimum Data Collection Approach, Fatima A. Tenorio, Juan I. Rattalino Edreira, Juan Pablo Monzon, Fernando Aramburu-Merlos, Achim Dobermann, Armelle Gruere, Juan Martin Brihet, Sofia Gayo, Shawn Conley, Spyridon Mourtzinis, Nester Mashingaidze, Alex Sananka, Stephen Aston, Jonathan J. Ojeda, Patricio Grassini

Department of Agronomy and Horticulture: Faculty Publications

Context: Agronomic data such as applied inputs, management practices, and crop yields are needed for assessing productivity, nutrient balances, resource use efficiency, as well as other aspects of environmental and economic performance of cropping systems. In many instances, however, these data are only available at a coarse level of aggregation or simply do not exist.

Objectives: Here we developed an approach that identifies sites for agronomic data collection for a given crop and country, seeking a balance between minimizing data collection efforts and proper representation of the main crop producing areas.

Methods: The developed approach followed a …

High Target Homology Does Not Guarantee Inhibition: Aminothiazoles Emerge As Inhibitors Of Plasmodium Falciparum, Sandra Johannsen, Robin M. Gierse, Arne KrüGer, Rachel L. Edwards, Vittoria Nanna, Anna Fontana, Di Zhu, Tiziana Masini, Lais Pessanha De Carvalho, Mael Poizat, Bart Kieftenbelt, Dana M. Hodge, Sophie University Of Nebraska-Lincoln,, Daan Bunt, Antoine Lacour, Atanaz Shams, Kamila Anna Meissner, Edmarcia Elisa De Souza, Melloney Dröge, Bernard Van Vliet, Jack Den Hartog, Michael C. Hutter, Jana Held, Audrey R. Odom John, Carsten Wrenger, Anna K.H. Hirsch

Department of Agronomy and Horticulture: Faculty Publications

In this study, we identified three novel compound classes with potent activity against Plasmodium falciparum, the most dangerous human malarial parasite. Resistance of this pathogen to known drugs is increasing, and compounds with different modes of action are urgently needed. One promising drug target is the enzyme 1-deoxy-D-xylulose-5- phosphate synthase (DXPS) of the methylerythritol 4-phosphate (MEP) pathway for which we have previously identified three active compound classes against Mycobacterium tuberculosis. The close structural similarities of the active sites of the DXPS enzymes of P. falciparum and M. tuberculosis prompted investigation of their antiparasitic action, all classes …

Soil Carbon And Nitrogen After Eight Years Of Rotational Grazing In The Nebraska Sandhills Meadows, Gandura O. Abagandura, Martha Mamo, W. H. Schacht, Aaron Shropshire, Jerry Volesky

Department of Agronomy and Horticulture: Faculty Publications

Grassland provides many ecosystem services; therefore, sustainable management practices of grassland are crucial for maintaining and enhancing its ecosystem health and resilience. Rotational grazing at a high stocking density (a.k.a., ultrahigh stocking density) is purported to sequester greater amounts of carbon (C) in grassland soils than rotational grazing at low stocking densities. This study was conducted in the Nebraska Sandhills meadows for eight years to evaluate how rotational grazing with different stocking densities can affect soil C and total nitrogen (TN) in bulk soils, soil organic matter fractions, and sequestration rate. The grazing management included a high stocking density with …

Genome-Wide Association And Genomic Prediction For Iron And Zinc Concentration And Iron Bioavailability In A Collection Of Yellow Dry Beans, Paulo Izquierdo, Rie Sadohara, Jason Wiesinger, Raymond Glahn, Carlos Urrea, Karen Cichy

Department of Agronomy and Horticulture: Faculty Publications

Dry bean is a nutrient-dense food targeted in biofortification programs to increase seed iron and zinc levels. The underlying assumption of breeding for higher mineral content is that enhanced iron and zinc levels will deliver health benefits to the consumers of these biofortified foods. This study characterized a diversity panel of 275 genotypes comprising the Yellow Bean Collection (YBC) for seed Fe and Zn concentration, Fe bioavailability (FeBio), and seed yield across 2 years in two field locations. The genetic architecture of each trait was elucidated via genome-wide association studies (GWAS) and the efficacy of genomic prediction (GP) was assessed. …

Environmental Biology Masters Capstone, Antonio Gonzalez-Pita

Regis University Student Publications (comprehensive collection)

Human wildlife interactions (HWI) pose a complex challenge for wildlife managers. Human encroachment into wildlife habitat and the growing number of outdoor recreationists are increasing the frequency of contact and conflict, especially in regions such as the Front Range of Colorado. Geographic information systems (GIS), which use a combination of remote sensing and environmental survey data, allow for predictive spatial analyses of where human wildlife interactions are likely to occur. I used publicly reported observations of moose to create spatial predictive maps in a species distribution model framework. Slope and elevation were shown to be the strongest predictors of HWI, …

Whatever Happened To The Snapdragon Family?, W. John Hayden

Biology Faculty Publications

The short answer is DNA sequencing and phylogenetic systematics.

Effect Of Dietary Flavonoids On Growth In Saccharomyces Cerevisiae, Vivian Rivera

Mahurin Honors College Capstone Experience/Thesis Projects

Plant foods contain a diversity of biologically active compounds called phytochemicals, produced by plant species as secondary metabolites. A phytochemical group known as flavonoids has received much scientific attention in recent times with respect to their antioxidative and anti-inflammatory roles. This investigation examined how quercetin and naringenin, the most common dietary flavonoids, affect growth potential of yeast under optimal and stress conditions (temperature, glucose, and oxidative stress). Using Saccharomyces cerevisiae as a model, a dose dependency effect of quercetin and naringenin was observed under optimal conditions when liquid cultures were treated with three different concentrations (75 μM, 150 μM, and …

Wildflower Of The Year, White Turtlehead (Chelone Glabra), W. John Hayden

Biology Faculty Publications

White Turtlehead is a perennial herb rising from a rhizomatous rootstock.

Evolutionary Origins Of Secondary Growth - The Periderm Perspective: Integrating Evidence From Fossils And Living Plants, Madison A.K. Lalica

Cal Poly Humboldt theses and projects

Periderm is a structural feature with roles in protection of inner plant tissues and wound healing. Knowledge of periderm occurrences in the fossil record and living lineages outside the seed plants is limited and its evolutionary origins remain poorly explored. Here, I review the known taxonomic distribution of canonical periderm (typical ontogenetic stage) and wound periderm (self-repair mechanism). To this sparse body of data I add new observations and experiments on living plant lineages and new occurrences from the fossil record. One of the latter, documented in the new early euphyllophyte species Nebuloxyla mikmaqiana, joins the oldest known periderm …

Characterizing New Plant Fossils With Woody Growth From The Battery Point Formation Of Quebec (Canada), Emma T. Casselman

Cal Poly Humboldt theses and projects

The oldest woody growth has been recognized in several Early Devonian (ca. 410-395 Ma) euphyllophytes. Their taxonomic diversity is difficult to evaluate due to a lack of quantitative methods for comparing plants based on secondary xylem anatomy. In turn, this hinders understanding of their implications for the evolution of plant development. To develop metrics that quantify secondary xylem anatomy and allow for conclusive comparisons, I investigated extant taxa and Early Devonian fossil woody taxa. I developed multiple metrics for quantifying tracheid size as a function of position in the secondary xylem and tested them on a dataset of extant gymnosperms. …