Summary: After reading the article "Every Forest Begins with a Seed," students build their won seed traps and investigate questions about seeds and seed dispersal.

Season: This inquiry can be conducted in fall or spring, although seed diversity will probably be lower in springtime.

Time needed: Four to six weeks, or parts may be completed separately in less time.

Curriculum connections: Ecology, environmental science, mathematics, engineering, language arts, and extensions that address life cycles and physics.

Learning goals and skills: Science processes--observing, classifying, measuring, defining questions, predicting, designing experiments, gathering data, keeping records, and interpreting information; science content--seed structure, seed dispersal, dispersal agents, and adaptation; language arts--interpreting and presenting information orally and in writing and extensions that cover nature descriptions and poetry; mathematics--ranking, addition, percentages, bar charts, and extensions that address velocity and rates; and other --collaborating with peers and appreciating biological diversity.

Background: Forests are being logged at an unprecedented rate. some logging practices are more sustainable than others. To help save forests, ecologists like David Gorchov study specific types of logging to determine which methods are the most sustainable. Critical questions to investigate include such ideas as: What seeds land in a cleared area? How do the seeds get there? Which seeds are likely to grow into mature trees? Can cleared areas recover?

Materials: You will need to provide 30 to 40 seed-collection containers, such as a pie tin, buckets, or plastic food-storage bins; stakes to secure each container to ground; duct tape or string to fasten each container to a stake; sellable plastic bags (to store the seeds); markers (to label the bags); paper towels; and a tree identification guide (optional).

MAKE IT HAPPEN

• Take students to an area where there are several kinds of trees and speed 15 to 20 minutes exploring the site. Ask: How would you describe each type of tree (size, bark, leaf shape, color, and so on)? Is there evidence of animals near or on the trees? How many different kinds of trees are there at the site? (If students don't know the names of the trees, ask them to count the number of different species they see.)
• Have students record their observations and draw a diagram of the trees and their locations at the site. Next, have students collect seeds and sort them by color, mass, species, shape, size, texture, and source (parent plant or tree). Using data from the sorting experience, make a bar or pie chart describing seed varieties. Discuss all of the ways seeds can travel (wind, water, animals, and people).
• Explore the various ways seeds travel by dropping seeds from varying heights, or by dropping seeds varying levels of wind (to create different wind levels, use a multi-speed fan). Record and measure findings.
• Now ask groups of students to write predictions about seed dispersal based on the information they've gathered, then write a proposal for using seed traps in an investigation.
• Invite each group to present their investigation ideas orally.
• Let each group exchange its proposal with another team. Visit each group to provide feedback Ask: Is the proposal related to seeds and trees? Is there a prediction? Are the methods clear and feasible? Are any steps left out? Are the materials available? Will the inquiry be safe for students and for the natural surroundings? Invite students to change their proposal if they see a way to improve their study. Come to a consensus about the best proposal(s) for the class to investigate. You may want to combine ideas from several teams. Once the class has chosen proposals to investigate, students should build the traps with the appropriate materials and place them in locations that best test their predictions. For example, place the traps at regular distances from a clump of trees ( or forested area) to the middle of a clearing to test predictions about which seeds travel farthest in nature. Check traps once or twice a week. Collect seeds in plastic bags and label the location and date. The traps should remain in place for at least three weeks.

• Hold group discussions about students' seed-trap experiences. Ask: Is important for seeds to travel? Why or why not? How might the color, shape, size, or texture of a seed help it travel? How might short-distance seeds reach new locations? Are you a seed predator? Formulate a new inquiry based on the findings, such as, "Of all the seeds collected in the seed traps , which ones will grow most readily?" To find out, students should predict which seeds will grow and which will not, then place each seed in a plastic bag with a dampened paper towel to germinate. Record findings and discuss expected results and surprises. Afterwards, students can design a new seed trap to improve the results of their study.

• Design your own seeds, make models, and see how far they travel when they dropped.
• Compose a story about a seed that traces a journey from the twig to a final place of grow. Make sure the story is descriptive, vivid , and scientifically accurate.
• Share your stories with peers.
• Examine a seed thorough a magnifying lens. Think of as many analogies as you can about the seed. What do the seed's texture, patterns, and shape remind you of? create poems using your analogies.
• Create a chart or mural of different seed types.

• For younger students--Find evidence outside, or in books, that animals eat seeds. Or, list the seeds we use for food. Visit a local grocery store to observe and collect foods with seeds.
• For older students--Investigate how different seed types counter gravitational forces (gravity causes objects to fall 9.8 meters/second2). Students measure rate of fall with stopwatch and meterstick.
• For schools with few trees--Elm, ash, and tree-of-heaven trees commonly grow in urban areas. Weeds and other plants that produce seeds could also by included in your investigation. Try placing a few trial seed traps in various locations to see what you get.

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