Grades 3-5 Lesson Plan - Saving the Big Trees

Map 9 Main Page

Core Map: [Tourist Map of the Yosemite District, 1936] in Plumb, Stanley, ed. The Four Seasons in Yosemite National Park. Yosemite Park and Curry Co., 1936. Newberry Library call number: Case folio F868 .Y6A33 1940 (Printable PDF version of the Core Map)

Resources related to Map 9.
Curator's Notes for Map 9.

Overview
Besides the majesty of the landforms in Yosemite, John Muir marveled at the Big Trees - the Giant Sequoias. In this lesson students use the core map to obtain information about the Big Trees for measuring and graphing. In addition, students judge whether the Big Trees should be preserved or conserved.

Objectives
By the end of this lesson student are expected to:

1. identify locations of the Big Trees on the core map and in the United States
2. obtain data to construct a graph showing the girth and height of selected Big Trees in Yosemite National Park.
3. evaluate whether the Big Trees should be preserved or conserved.

Key Terms
national park, grove, preservation, conservation, coniferous, deciduous

Materials
Computer image or overhead of the core map; copies of the core map; selections from The Sequoia and General Grant National Parks; graphing paper, colored pencils; yarn

Time
Two class periods, plus homework

Getting Started

1. Give students a brief history of the Yosemite region becoming a national park and of John Muir's association with the park (see Curator's Notes and Resources).

2. Distribute the core maps to students. Have students work in pairs to decode the map symbols. Discuss what symbols they found and what they represent. Clarify any map features or symbols which students do not understand.

3. Read selected passages from "The Sequoia and General Grant National Parks" to students. Clarify that the Big Trees are a gigantic Sequoia and that Sequoias are a type of coniferous tree. Discuss attributes of the Sequoia and of conifers.

4. Locate the Mariposa and Tuolumne Groves on the core map. Select "Show Sites" from the menu on the core map and click on the highlighted areas near the groves to see pictures of them.

Developing the Lesson

1. Focus on the "Facts About Yosemite National Park" found on the core map, particularly the measurements of the trees. If necessary, discuss the terms girth, diameter, base, and height.

2. Divide students into eight groups and assign each group one of the trees listed. Have students measure a length of yarn representing the girth of their tree. In a large room, gym, or outside, have students circularly lay the yarn to represent the girth of their tree. Label each. (In a limited space place smaller "trees" inside of larger ones.) Ask students to find out how many students could stand around the tree; measure the diameter and compare to that on the map. Discuss the relationship between girth and diameter of the tree. (Diameter does not include bark.)

3. Have each student construct a double bar graph to show the height and girth of each tree.

4. Discuss relationships seen on the graph. Does girth predict height; that is, are the highest trees also the widest? Which tree is the tallest, widest?

5. Discuss the difference between preservation and conservation.

6. One of John Muir's concerns was the use of the Big Trees as timber. He fought to have Mariposa and Tuolumne Groves preserved. Outside of Yosemite National Park and other protected areas, such as Sequoia National Park, Sequoias can be cut. Reading passages from John Muir's essay on the Sequoia and General Grant National Parks (see Resources) discuss with your students why Muir thought it was important to preserve these groves as they existed in his time. Also discuss under which circumstances is it now considered acceptable to cut or burn trees in national parks. For example, controlled burns are now implemented in some national parks in order to remove underbrush and to encourage diversity of forest species, thus reducing the risk of catastrophic fires. Ask the students whether this practice is an example of conservation or preservation as Muir would have understood the terms.

7. Have each student write an essay in which the issue of saving the Big Trees is addressed: Should all the Big Trees be preserved (or is it OK for some to be cut, and under what circumstances)? Allow for differing points of view, but ask that students support their point of view.

Evaluation
Using a 1-4 scale (4=excellent, 3=good, 2= fair, 1=poor) assess student performance as follows:

For 4 points, the student participates in all discussions. Student accurately constructs and labels the graph and draws logical and insightful conclusions from the data. The essay states a point of view answering the question and has supportive evidence/ideas.

For 3 points, the student participates in all discussions. Student constructs and labels the graph and draws obvious conclusions from the data. The essay states a point of view answering the question and has some supportive evidence/ideas.

For 2 points, the student listens to all discussions. Student constructs and labels the graph, but there is missing detail. Student draws illogical/unsupported conclusions from the data. The essay states a point of view answering the question but does not have supportive evidence/ideas or support does not address the issue.

For 1 point, the student does not participate in discussions. Student has difficulty in constructing and/or labeling the graph and is unable to draw conclusions from the data. The essay states a point of view answering the question but has no supportive evidence/ideas.

Extensions

1. Share "Sequoia Notes" from "The Sequoia and General Grant National Parks." Discuss the special attributes of the Big Trees.
2. Graph the elevations and/or waterfall heights using "Facts About Yosemite National Park."
3. Have students graph information using graphing software and discuss how different types of graphs show the information more accurately than others.
4. In 2002, the American West experienced its most devastating fire season in recorded history. Using newspaper accounts and/or websites, have students write a brief essay on how the conservation policies of the last century affected these fires.