Part
1: Field Protocol
Guiding Field Question:
- What are the two or three most abundant tree species in the plot?
Definitions:
- Tree = live woody stem with > 15 cm CBH
- CBH = circumference at breast height (1.35 m from the ground)
- Most Abundant Tree Species = any tree species representing the greatest relative density in the field site
Materials (one per group):
- Clipboard, Pencil, Science Notebook
- Flexible measuring tape, tree guide, calculator
- Tree
Density Data Sheet
Pre-requisites:
- GLOBE Carbon Cycle Field Protocols for Sample Site Set-up (Follow link and choose Standard or Non-Standard Sample Site Set-up)
- Practice identifying common New England Tree species with field guide
- Discussion of how to maintain a meaningful Science
Notebook. For more information and examples, see the Science
Notebook Guide
Estimated Time:
- 1 hour
What to do and how to do it:
- INTRODUCTION (INDOORS): Background provided on field site set-up and abundance measure for determining most abundant tree species.
- INTRODUCTION (OUTDOORS): Class sits in circle in field site. Instructor indicates the boundaries of the field site and divides students into four small groups to conduct observations per subplot. The expectations for the initial field observations are explained.
- The first 3 minutes students work individually in silence to take time to become oriented/acquainted. Emphasize the use of the senses. Touch. Look. Listen. This helps students focus on the forest. Also students walk the boundaries of the subplot. The instructor will indicate with a whistle when 3 minutes have passed. The following 5 minutes students record their qualitative observations (words and sketches) of the forest. Tell students to keep in mind the guiding question: What are the two or three most abundant tree species in the plot?
- The class reconvenes and shares some initial observations. What kind of forest is it? Are there more deciduous or coniferous trees, or an even mix? What species did you recognize? What questions do you have?
- Instructor explains the recording of tree species and number of stems per subplot and use/creation of a data sheet for the quantitative data.
- Working collaboratively in the small group, students identify, count, and record all trees (> 15 cm in CBH) in the subplot.
- WRAP-UP: Return to classroom and compile each group’s data. Then calculate the two to three most abundant tree species in the field site using the equations provided on the Tree Density Data Sheet.
- Using the evidence gathered in the field study, respond to the guiding question in the science notebook. Communicate and share responses as a whole class.
*For a more in-depth field protocol, continue to follow the
GLOBE Carbon Cycle protocols found on their Field Measurements webpage.