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  • How Now Round Crown? Predicting the Energy Future of Tree Crowns
Illustration of two kids, standing back to back, both writing on notebooks. In the background are two other kids that are measuring the trunk width of two trees.
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How Now Round Crown? Predicting the Energy Future of Tree Crowns

  • Article
  • Middle School
  • 1 Classroom Period
  • Active Forest Management
  • Engineering and Forest Products
  • Energy
  • Fertilizer
  • Forest management
  • Modeling
  • Potential Energy
  • Tree Crown
Illustration of two kids, standing back to back, both writing on notebooks. In the background are two other kids that are measuring the trunk width of two trees.
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Pine trees cover much of the Southeastern United States. When older pine trees are cut for making wood products, only the trees’ boles are used. The scientists in this study wondered if there might be a use for the trees’ crowns as well. In particular, they wondered whether the trees’ crowns might one day be a source of energy.

How Now Round Crown? Predicting the Energy Future of Tree Crowns

The National Inquirer cover for the Bioenergy issue.

Part Of

Bioenergy - Vol. 9 No. 1

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  • PDF preview of How Now Round Crown FACTivity.
    The questions you will answer with this activity are: Why are trees managed differently? What are some of the differences in managed trees versus unmanaged trees? Materials: Blank sheet of...

    FACTivity – How Now Round Crown

    • Activity
    • Middle School
    • 1 Classroom Period
    • Engineering and Forest Products
    • Class Discussion
    • Creative Activity
    • Outdoor Activity
    The questions you will answer with this activity are: Why are trees managed differently? What are some of the differences in managed trees versus unmanaged trees? Materials: Blank sheet of...
    • Explore Activity
    • Download FACTivity
    • Explore Activity
    • Download FACTivity

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    How Now Round Crown? Predicting the Energy Future of Tree Crowns

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Glossary

View All Glossary
  • average

    (av (ǝ) rij): A value that is computed by dividing the sum of a set of terms by the number of terms.

  • biomass

    (bī ō mas): The amount of living matter (in a unit area or volume of habitat).

  • data

    (dā tǝ or da tǝ): Factual information (such as measurements or statistics) used as a basis for reasoning, discussion, or calculation.

  • economically

    (e ko nom ik le): Having to do with the management of money in a home, business, or government.

  • forest manager

    (fȯr ǝst ma ni jǝr): A person who manages a forest; in the Forest Service, forest managers focus on managing vegetation, restoring ecosystems, reducing hazards, and maintaining forest health (definition from USDA Forest Service).

  • hectare

    (hek tär): A unit of area equal to 10,000 square meters.

  • megagram

    (meg uh gram): A unit of mass equal to 1,000,000 grams. A megagram is equal to 1.1 ton, or 2,200 pounds. Symbol: Mg

  • megawatt hours

    (meg uh wat ow ürs): one joule of energy per second. If a 100-watt light bulb is turned on for 1 hour, the energy used is 100 watt-hours.

  • net

    (net): An amount, profit, weight, price, result, that is left after another amount is subtracted.

  • renewable

    (ri nü ǝ bǝl): Capable of being replaced by natural ecological cycles or sound management practices.

  • resource

    (rē sȯrs): A usable stock or supply (as of money, products, or energy).

  • Andy Scott working in the field

    Andy Scott

    Soil Scientist

    I enjoy science because I get to continually learn about things and help others learn. Every experiment has three great parts for me. First, each experiment means I’m doing something...
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  • Natural Inquirer bee with a magnifying glass

    Tom Dean

    Soil Scientist

    My favorite science experience is discovering how trees work: how they stand up, how they grow, and how they withstand changes in the environment year after year.
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Jump To

  • Education Standards
  • Educator Guide
  • Lesson Plans
  • Education Files
  • Project Learning Tree

Standards addressed in this Article:

The Next Generation Science Standards (NGSS) are a set of K-12 science education standards emphasizing inquiry-based learning, real-world applications, and integrating engineering practices, aiming to deepen understanding of science while promoting critical thinking and problem-solving skills.
  • ETS1.A-M1
    The more precisely a design task’s criteria and constraints can be defined, the more likely it is that the designed solution will be successful. Specification of constraints includes consideration of scientific principles and other relevant knowledge that is likely to limit possible solutions.
  • ETS1.B-M1
    A solution needs to be tested, and then modified on the basis of the test results, in order to improve it.
  • ETS1.B-M2
    There are systematic processes for evaluating solutions with respect to how well they meet criteria and constraints of a problem.
  • ETS1.B-M3
    Sometimes parts of different solutions can be combined to create a solution that is better than any of its predecessors.
  • ETS1.B-M4
    Models of all kinds are important for testing solutions.
  • ETS1.C-M1
    Although one design may not perform the best across all tests, identifying the characteristics of the design that performed the best in each test can provide useful information for the redesign process—that is, some of the characteristics may be incorporated into the new design.
  • ETS1.C-M2
    The iterative process of testing the most promising solutions and modifying what is proposed on the basis of the test results leads to greater refinement and ultimately to an optimal solution.
  • PS3.A-M2
    A system of objects may also contain stored (potential) energy, depending on their relative positions.
  • PS3.A-M3
    The term “heat” as used in everyday language refers both to thermal energy (the motion of atoms or molecules within a substance) and the transfer of that thermal energy from one object to another. In science, heat is used only for this second meaning; it refers to the energy transferred due to the temperature difference between two objects.
The Common Core Standards are educational benchmarks in the United States that outline clear expectations for what students should know and be able to do in English language arts and mathematics from kindergarten through 12th grade, aiming to ensure consistency and coherence in education nationwide.
  • Cite specific textual evidence to support analysis of science and technical texts.
  • By the end of grade 8, read and comprehend science/technical texts in the grades 6-8 text complexity band independently and proficiently.
  • Determine the central ideas or conclusions of a text; provide an accurate summary of the text distinct from prior knowledge or opinions.
  • Follow precisely a multistep procedure when carrying out experiments, taking measurements, or performing technical tasks.
  • Determine the meaning of symbols, key terms, and other domain-specific words and phrases as they are used in a specific scientific or technical context relevant to grades 6-8 texts and topics.
  • Analyze the structure an author uses to organize a text, including how the major sections contribute to the whole and to an understanding of the topic.
  • Analyze the author's purpose in providing an explanation, describing a procedure, or discussing an experiment in a text.
  • Integrate quantitative or technical information expressed in words in a text with a version of that information expressed visually (e.g., in a flowchart, diagram, model, graph, or table).
  • Distinguish among facts, reasoned judgment based on research findings, and speculation in a text.
  • Compare and contrast the information gained from experiments, simulations, video, or multimedia sources with that gained from reading a text on the same topic.
Social Studies Standards are educational guidelines outlining the essential knowledge, skills, and concepts students should learn in subjects such as history, geography, civics, and economics, aiming to provide a comprehensive understanding of societal structures, historical events, and global perspectives.
  • People, Places, and Environments
  • Production, Distribution, and Consumption
  • Science, Technology, and Society
  • Time, Continuity, and Change

What Is a Natural Inquirer Journal?

Three Natural Inquirer journal covers with NI bee

 

A Natural Inquirer journal is a collection of 4-8 articles on a related science topic. Journals are written for a middle school audience, but they can also be adapted for both high school students and advanced upper elementary students. Some journals are particularly suited to high school students; you can find our grade level recommendations in the tags on the product page or by filtering journals by grade level.

Journals include:

  • Four to eight articles based on published, peer-reviewed research papers; the articles keep the research paper format (see more below) but are written in language students can understand.
  • A FACTivity for each article, which is an activity to complete after reading the article. The FACTivity helps reinforce major science concepts from the article. These activities are designed to be easy to implement, with few material requirements and options for adapting them for your audience or available resources. Some articles in a journal may have two FACTivities.
  • A short “Welcome to the journal” article about key background information and science concepts that unify the articles included in the journal
  • A glossary of new terms for each article and the introductory materials.
  • A list of related Natural Inquirer publications for each article as well as outside references.
  • Standards correlations, including Next Generation Science Standards, addressed in the articles and the FACTivities.

Journals may also include additional essays (called spotlights), other activities (like crossword puzzles or vocabulary challenges), and more.

 

A screenshot of the article resource tile for "A Flame Changer" showing the three different format option buttons.

Reading Modes

Journals are available in three different formats:

  • Hard copies can be ordered from the website and shipped, all free of charge.
  • PDF versions of the printed journal can be downloaded free on the website. The PDF version directly replicates the content and layout of the printed version. You can also download individual articles as pdfs.
  • The “Read Distraction Free” option allows the individual articles to open in their own window, without the rest of the website being visible. These articles can be found under the “Articles” tab. This version allows readers to scroll to particular sections of the article using the sidebar menu on the left side of the screen. This version also has interactive Reflection Sections and Number Crunches. Students can enter their answers, submit them, and then receive the correct answers to double-check their work. Submitted answers are not saved on the website and will disappear once the window is closed.

What's in a Natural Inquirer Article?

Here, we'll go into more detail about the parts of a Natural Inquirer article and give you some ideas about how they can be used.
  1. Meet the Scientists

    This section introduces the scientists (and others) who worked on the study. In their own words, they each share a memorable science experience, a favorite research project, or something they learned during the course of their education or research.

    Use this section to:

    • Introduce kids to the variety of people who work in science
    • Introduce kids to the variety of scientific fields and give brief descriptions of science-related jobs
    • Explore ways that people interact with science every day

    Next Generation Science Standards (NGSS) applications:

    • Science and Engineering Practices
    • Crosscutting Concepts: Influence of Science, Engineering, and Technology on Society and the Natural World

    Note that specific standards for this particular monograph are linked on this educator guide tab.

    Other resources:

    Many of the scientists and engineers featured in this section are also featured on our collector cards. Learn more about their work, how they got interested in their fields, and interesting projects they worked on. Cards can be printed as posters, too.

    A sample Meet the Scientists page, showing four different scientists
  2. Thinking About Science

    This section briefly describes a concept about science or scientific research. This overview can touch on topics like

    • study type (longitudinal study, quantitative vs. qualitative data),
    • behaviors of scientists (conducting literature reviews, collaborating with other specialists, replicating earlier studies),
    • the practice of science (the scientific method, engineering design, data collection, randomization, controls and variables),
    • or other aspects of science (bias, correlation vs. causation).

    Use this section to:

    • Reinforce steps in the scientific method and the process of science
    • Encourage students to think about the practice of science and what it can and cannot tell us
    • Consider the many types of scientific study and what information each type can provide

    Next Generation Science Standards applications:

    • Science and Engineering Practices
    • Life Science Disciplinary Core Ideas (depending on topic)
    • Most Crosscutting Concepts (depending on topic)

    Note that specific standards for this particular monograph are linked on this educator guide tab.

    Other resources:

    You can use key words to search for other or related scientific topics on our website (e.g. “longitudinal study,” “bias,” or “sampling”).

    A sample Thinking About Science page from a recent monograph
  3. Thinking About the Environment

    This section provides a brief overview of a topic or concept in environmental/life science. The topic or concept is directly related to the research study that follows. Examples of topics include the carbon cycle, the water cycle, habitat fragmentation, phenology, biodiversity, and ecosystem services.

    Use this section to:

    • Provide important background information to help students understand the research study
    • Serve as a quick reference during reading or class instruction
    • Connect the research article with other activities or media on the same topic

    Next Generation Science Standards applications:

    • Life Science and some Earth Science Disciplinary Core Ideas (depending on topic)
    • Most Crosscutting Concepts (depending on topic)

    Note that specific standards for this particular monograph are linked on this educator guide tab.

    Other resources:

    You can use key words to search for more resources on life or earth science topics on our website (e.g. “habitat,” “carbon,” or “genetics”).

    A sample "Thinking About the Environment" section from a recent monograph
  4. Introduction

    This section begins the scientific article format. Much like the published, peer-reviewed study this article is based on, the introduction provides background information for the study – what is currently known and what remains unknown. The introduction culminates in the question(s) the study hopes to answer.

    The introduction is also the first section with a Reflection Section. This section includes two or three questions to help kids reflect on what they’ve just learned in the Introduction. If they are using the online distraction-free reading mode, they can answer these questions directly on the website.

    Use this section to:

    • Review important background information that kids need to understand the study
    • Connect the study to the concepts addressed in the Thinking About Science and Thinking About the Environment sections
    • Understand research questions and hypotheses, including generating their own hypotheses given what they already know

    Next Generation Science Standards applications:

    • Life Science and some Earth Science Disciplinary Core Ideas (depending on topic)
    • Most Crosscutting Concepts (depending on topic)

    Note that specific standards for this particular monograph are linked on this educator guide tab.

    Other resources:

    Use one of the guided reading lesson plans to help kids follow the format of a scientific paper.

    A sample introduction page from "Hidden in Plain Sight"
  5. Methods

    This section is the nuts and bolts of the study design – the who, what, when, where, why, and how of the research. Contained within the Methods section are usually maps of the study location or the set-up of study plots, as well as details about what data was collected and how.

    The Methods section also ends with a Reflection Section – two or three questions to help students think through what they just read. These questions are interactive on the distraction-free reading mode.

    Use this section to:

    • Show students how experiments and studies are designed and carried out
    • Explore sampling methods and randomization
    • Introduce various data collection tools (e.g. camera traps, surveys, insect collection tools, weather stations, etc.)
    • Explain bias and how studies are designed to remove bias
    • Help students gain experience with map reading

    Next Generation Science Standards applications:

    • Life Science and some Earth Science Disciplinary Core Ideas (depending on topic)
    • Most Crosscutting Concepts (depending on topic)

    Note that specific standards for this particular monograph are linked on this educator guide tab.

    Other resources:

    Many Methods and Findings sections contain Number Crunches, which are simple math exercises designed to help students interact with the data from the study.

    A sample methods section of a monograph article showing a map
  6. Findings

    This section summarizes the data collected during the study. The Findings section usually includes data tables or graphs and highlights the significant data points from the study. This section often mentions statistical analysis or the use of computer programs to model or analyze the data, though these methods are only discussed generally.

    The Findings section also ends with a Reflection Section – two or three questions to help students think through what they just read. These questions are interactive on the distraction-free reading mode.

    Use this section to:

    • Have students practice reading and interpreting graphs and tables
    • Compare results between variables and controls
    • Explain the concept of statistical significance
    • Discuss how no data or negative results still provide valuable information

    Next Generation Science Standards applications:

    • Life Science and some Earth Science Disciplinary Core Ideas (depending on topic)
    • Most Crosscutting Concepts (depending on topic)

    Note that specific standards for this particular monograph are linked on this educator guide tab.

    Other resources:

    Search the website for “map” or “graph” to find activities where students can practice making and reading maps and graphs.

    The beginning of a Findings section featuring a large data table
  7. Discussion

    This section concludes each article. In it, we summarize the main findings of the scientists’ study. Additionally, we present the scientists’ ideas about the limitations of their study, the big-picture impacts of their research, and the scientists’ plans for future study or action.

    The Discussion section ends with a Reflection Section – two or three questions to help students think through what they just read, especially general take-aways from the study. These questions are interactive on the distraction-free reading mode.

    Use this section to:

    • Discuss what conclusions can and cannot be drawn from the available data
    • Explain the difference between correlation and causation
    • Explore study limitations and opportunities for further study
    • Brainstorm ways the study findings could be applied to real-world situations

    Next Generation Science Standards applications:

    • Life Science and some Earth Science Disciplinary Core Ideas (depending on topic)
    • Most Crosscutting Concepts (depending on topic)

    Note that specific standards for this particular monograph are linked on this educator guide tab.

    Other resources:

    Use the “Designing Your Own Study” resource page for videos of scientists discussing their own research studies. The page also includes educator resources to help students plan their own scientific studies.

    The beginning of the conclusion of "Hidden in Plain Sight"

Additional Resources on the Website

A screenshot of the product tabs for an NI monographOn the website, we pair each journal with a variety of other resources, as well. Use the tabs on the product page to browse through the following:

  • Related activities, including the FACTivity for each article
  • An “About” essay that gives some larger context for the research the scientists conducted or more information about the science topic from the journal
  • A glossary of all boldfaced terms from the journal
  • A “Scientists and Collaborators” page that lists the people involved in the studies in the journal; click on a researcher to reach their bio page and see what other articles they might be featured in
  • A “Related Content” page that lists both Natural Inquirer resources about similar topics and also outside reference materials

Article Selection and Review

Natural Inquirer partners with the USDA Forest Service, so we source research studies by Forest Service scientists that have been peer-reviewed and published in reputable journals. Some of our articles have also been created in collaboration with scientists from other Federal agencies, such as U.S. Geological Survey and the United Nations Food and Agriculture Organization, universities, and other non-profits.

All journal articles are reviewed by scientists who conducted the original research study to verify scientific accuracy. Journals are also reviewed by student editorial review boards of middle or high school students before publication. Additionally, all journals are reviewed by the Forest Service and the U.S. Department of Agriculture before publication.

A screenshot of the citation for "Lights, Camera, Tracks"Every journal article includes a citation of its source study. Many educators pair the original research paper with our article to help more advanced students learn how to read formal research papers. The journal article then serves as adapted primary literature, bridging the two articles.

Lessons

  • PDF preview for the Bioenergy lesson plan
    In this lesson plan, students learn about bioenergy, then stage a debate in a town considering switching from fossil fuels to biomass.

    Bioenergy Lesson Plan

    • Lesson Plan
    • Middle School
    • 2-3 Classroom Periods
    • Biomass
    • Class Discussion
    • Debate
    • Fossil Fuels
    • Group Project
    In this lesson plan, students learn about bioenergy, then stage a debate in a town considering switching from fossil fuels to biomass.
    • Explore Lesson Plan
    • Downloan Lesson Plan (PDF)
    • Explore Lesson Plan
    • Downloan Lesson Plan (PDF)

    Part Of

    A Chip Off the Old Block: Using Wood Energy to Heat Schools

  • PDF preview of the Questions Only lesson plan
    The goal of this lesson plan is to help students identify key concepts and develop their own interpretations of what they read. It includes 42 open-ended questions for them to...

    Lesson Plan – Questions Only

    • Lesson Plan
    • High School
    • Middle School
    • 2-3 Classroom Periods
    • Active Forest Management
    • Agriculture
    • Carbon
    • Citizen Science
    • Engineering and Forest Products
    • Fire
    • Insects
    • Pollinators
    • Pollution
    • Recreation
    • Social Science
    • Water
    • Wilderness
    • Wildlife
    • Class Discussion
    • Interpretation
    • Questions
    The goal of this lesson plan is to help students identify key concepts and develop their own interpretations of what they read. It includes 42 open-ended questions for them to...
    • Explore Lesson Plan
    • Download Lesson Plan (PDF)
    • Explore Lesson Plan
    • Download Lesson Plan (PDF)

    Part Of

    Bioenergy - Vol. 9 No. 1

  • PDF Preview of the Summary & Present Lesson Plan
    Students work in groups to analyze the Natural Inquirer article research study and give a brief presentation on their findings to their classmates. This lesson plan can be used with any Natural...

    Lesson Plan – Summarize and Present

    • Lesson Plan
    • High School
    • Middle School
    • 2-3 Classroom Periods
    • Active Forest Management
    • Agriculture
    • Carbon
    • Citizen Science
    • Engineering and Forest Products
    • Fire
    • Insects
    • Pollinators
    • Pollution
    • Recreation
    • Social Science
    • Water
    • Wilderness
    • Wildlife
    • Class Discussion
    • Presentation
    Students work in groups to analyze the Natural Inquirer article research study and give a brief presentation on their findings to their classmates. This lesson plan can be used with any Natural...
    • Explore Lesson Plan
    • Download Lesson Plan (PDF)
    • Explore Lesson Plan
    • Download Lesson Plan (PDF)

Education Files

Project Learning Tree

If you are a Project Learning Tree-trained educator, you may use “A Few of My Favorite Things” or “Trees for Many Reasons” as additional resources.

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