Fifteen Days of Spring
Creating a Record of Spring Leaf-Out in Your Schoolyard

Background
One of the best sources for observing spring's entrance in your area is found in your own schoolyard. Observing and recording a specific tree as it proceeds through its growth leads to inquiry into environmental changes. The resulting data is a visual picture of spring tree growth. In this lesson, students will be:

  1. Observing and Collecting Leaves
  2. Pressing Leaves
  3. Creating a Time-Line Book

Materials
· Journey North field journal or notebook
· Trees (easily accessible)
· A simple plant press (or a wooden plant press)
· Tree identification guides
· Art supplies: paper, glue, paint, ribbon, brushes or small sponges

Activity (Part I): Observing and Collecting Leaves
Begin this lesson before the deciduous trees in your area have begun to leaf out. Take your class out and as part of your phenology studies; watch for signs of swollen tree buds.

When the buds are beginning to break you can start this leaf-out lesson.



1. Choose a tree or a branch for each student or group of students to observe for the course of this lesson. These could be marked with yarn.

2. Every 2 days go out and observe the size of the emerging leaves.

3. In their Journey North field journals, have the students sketch the leaves to scale, measure the leaves, and/or collect a representative sample of leaves*. Record the day's high and low temperature, the weather conditions and other sensory observations on the same journal page. (The personal sensory observations make the journal more personal and more fun!)

4. Do this until the trees are fully leafed out, or until there is a substantial visual difference from start to finish. It should take less than 3 weeks if you are experiencing a normal spring.

5. Using tree identification guides, have students identify their trees and write some facts about the trees in their JN field journals.

* If there are enough leaves on the trees, have students collect the leaves and press them to use in Part Two in an art lesson to create a separate Leaf-Out Book.

Discussion
1. Do the leaves of all the trees selected for collecting emerge at the same time and the same rate? What could have caused the differences? the similarities?
2. How does the weather- temperatures, daylength, and atmospheric conditions- affect leaf emergence?
3. Were you able to identify trees easier after leaves began to emerge?
4. Did you notice any correlations between the leaf size and other things that you recorded in your journals (i.e. insect activity, bird activity, other plant or flower growth)?
5. How does the leaf-out in your area compare with other places in North America?

Activity (Part II) : Pressing Leaves