Keywords: Pennsylvania forests, leaf collection, id; Grade Level: seventh and eighth grades(MS); Total Time: Two to three weeks should be allowed for the entire project. Two 45-minute class periods are used to introduce and to wrap-up the project; Setting: This activity is done in the fall for two reasons. First the leaves are nearly ready to fall from the trees and, therefore, will not adversely affect the tree's photosynthetic production. Second, the leaves tend to be drier in the fall and will not be as likely to mold in the binders. First and last class periods may be inside or outside, remainder of the work will be done outside.
Concepts to Be Covered
- Pennsylvania forests (as well as many urban areas) contain diverse tree species.
- Certain species of trees tend to be found in distinct habitats depending on sunlight, water, and nutrients available.
- Using a field guide and/or dichotomous key, nearly anyone can identify many tree species.
Materials Needed
- various tree identification field guides
- dichotomous key for common trees in Pennsylvania
- three-ring binder or other similar storage medium
- handouts
Goals for the Lesson
- Students will become more observant of the world around them.
- Students will be able to recognize and identify trees commonly found in their neighborhoods and in the forests of Pennsylvania.
- Students will become familiar and confident in their abilities to use identification techniques and resources.
Pennsylvania State Standards: Environment & Ecology (4.2.7B, 4.4.7B); Science & Technology (3.1.7C, 3.3.7A)
Methods
- This lesson can be used as a stand-alone activity or in coordination with a unit on trees, forest ecosystems, or even the history of Pennsylvania.
- Students are briefly introduced to the process of identifying trees by leaf type (simple or compound), leaf arrangement (alternate or opposite), and leaf shape (margin, entire, toothed, lobed).
- Students will then compile a collection of leaves from 12 to 15 species of trees common to Pennsylvania. Students are given leaf collection requirements, leaf collection grade sheet and table, leaf collection appearance rubric, and a list of the leaves that are permitted . These leaves are displayed in a binder or similar package.
- Only one tree should be represented on each page. More than a single page may be used for a given species.
- The common name, scientific name, and leaf type (simple or compound) must be supplied for each tree exhibited.
- Student leaf collections will be shared with the class on the final day of the project. Students will vote (by private ballot) for awards to be given to the best collections in previously identified areas such as most creative display, best organized, or others identified by the students on the first day of the project.
Assessment
- Students receive points based on the accuracy of identification, leaf arrangement, scientific name, and neatness/organization. Examples of previous collections could be made available after the first year of implementing this project.
- Twelve different tree species must be represented to be able to earn full credit. The extra three species can be used as extra credit. I recommend these species be only worth half the point value of the twelve required samples.
Extensions/Alternatives
- This activity could also be done by providing a list of trees common to your area and instructing students to collect only specimens from those species.
- One extension of this activity could include examining leaf structure for stoma or pigments.
- A second extension could involve drawings of the leaves and the trees on which they are found as an art activity.
Author
Steven D. McAninch, Park Forest Middle School
