Plants have developed a variety of ways to disperse their seeds to new locations, allowing the young seedlings to avoid competition with their parent plants for sunlight, nutrients and water. Typically, the seeds begin the journey packaged in a “seed container,” or fruit.
There are ingenious seed containers. For example, seeds of maple and ash are contained in fruits with papery wings that catch the wind. Seeds of dandelion, asters and poplar trees are also wind travelers, relying on tufts of hair to keep their fruits airborne.
Animals are agents of seed dispersal. The applelike fruits of wild roses and mountain ash are eaten by animals that discard the seeds in a supply of starter fertilizer. Squirrels and chipmunks bury acorns and beechnuts, forgetting enough of them to ensure the next generation of oaks and beeches.
Others seeds travel as hitchhikers in fruits armed with sharp hooks or barbs that attach to the fur of passing animals or the clothing of passing people. Burdocks and beggar ticks are well-known hitchhikers.
And there are fruits called pods, seed containers that burst open along their seams with enough force to propel the seeds away from the parent plant. The pods of jewelweed, often called touch-me-not, explode when touched, sending their seeds into the air.
This activity allows children of school age to discover the variety of fruits and seeds that can be found outside in autumn and how the seeds are dispersed.
Seed hunt cards (1 for each team)
Paper bags for collecting (1 for each team)
Old wool socks (1 for each team)
. Prepare the Seed Hunt Card for each team. The card should list the following items: two different seed containers that animals might eat. (Don’t eat them yourself!); two different seed containers that travel at least three feet when you blow on them; two different seeds that stick to fur (and check the wool sock periodically to see what seeds are hitching a ride); two seed heads that have more than 20 seeds in them; two different fruits or seeds from a tree, and fruit that is a pod.
. Choose a woodland trail or open field for the hunt, planning a walk that offers as much plant diversity as possible. Off-road trails that meander through wooded areas are the perfect hunting ground. Do not be concerned about learning the names of all the plants, simply allow the children to collect samples of the fruits and seeds that they find.
. Plan for an adult to accompany each team of young children to ensure that no fruits or seeds are eaten and that the children keep their distance from poison ivy.
Form scavenger hunt teams of two to four children and assign an adult guide to each team. Have one child in each team wear an old wool sock over one shoe to pick up “hitchhikers.” Define the boundaries for the hunt and explain any “rules,” including the time limit.
At the end of the hunt, have each team introduce a fruit or seed that it found interesting. If possible, help them dissect the fruits to find the seeds. Discuss the means of dispersal for each kind of fruit and seed collected.