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Seed
Surprises
This fall
lesson accompanies and enhances the following lessons found in “Growing
in the Garden: K-3 Curriculum Growing Curiosity About Agriculture, Natural
Resources, Food, and People.”
 The
following three lessons are in PDF format.
Please let us know if you use these lessons
and how they fit into your current curriculum and activities by e-mailing your
comments to anderames@aol.com. THANK
YOU. |
Materials
- small paper bag or plastic sandwich bag (one
for each student)
- 6
to 10 ears of field corn (find at local grain elevator, from corn producer, or
at a store that sells bird, squirrel, and pet food)
- 6
to 10 pieces of aluminum foil (cut in 24” x 12” strips to wrap twice
around an ear of corn)
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Do
Scavenger Hunt: Give each student or
team of students a small paper bag or plastic sandwich bag and tell them to go
outside and search the playground for “natural seed packages.” This
would include fruits, pine cones, seed pods, acorns, walnuts, grass spikes,
etc. Give them time to gather up as many as they can find. Bring them indoors
and see which student or group found the largest assortment. (You may want to
show them the pictures of the “natural seed packages” found on this
web site. You may also want to assign this as homework in order for the
students to find a larger variety of seed pods. A class walk or field trip to
the country will also open up more opportunities to find a variety of seeds.)
Put all the “natural seed packages” together and discuss
where the seed is located in each one. Some seeds are found inside a protective
covering, like the black, gooey coating around a black walnut, or the pod on a
milkweed. You may want to create a guide for seed and plant identification by
drawing pictures of the seeds, pods, flowers, fruits as you discuss them.
Below are some plants with unique pods, spikes, flower heads, or fruits
where the seeds are neatly arranged.
Foxtail The seeds are in rows on each
side of the spike. |
Corn The seeds are arranged tightly in
rows along a center core or cob. |
Velvet leaf The seeds are in
compartments inside a pod. This plant is sometimes called “butter
print” because pioneer women would use the top of the seed pod as a stamp
to decorate pats of freshly churned butter. |
Sunflower The seeds are neatly packed,
pointed ends in, in the center of the faded flower head. |
Marigold Look below the dried petals
and inside the calyx which serves as a cup to hold the tightly packed long
slender seeds. |
Milkweed The seeds are neatly tucked in
a pod. When the pods dry and burst open, the white “fluff” carries
the seeds in the wind. |
Zinnia Remove the dried petals to
reveal the seeds which are attached in rows to the core - such as corn seed
attached to a cob. |
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Reflect
How were the seeds different from each other in
size, shape, color, number of seeds per plant or pod?
How were the
seeds protected by the plant? What did the pods look like? How did the pods
open so the seeds could come out?
Can you think of some seeds that drop
from the mother plant that don’t have a protective covering? grass
seeds, corn, maple seeds, and acorns
Note how neatly and
efficiently the seeds are arranged on the spike or in the pods. Can you think
of a better way to fit so many seeds into such as small area?
Demonstration: Have the
children work in groups of two or three. Give each group an ear of corn and a
piece of aluminum foil large enough to completely cover the ear of corn. Have
them wrap the foil around the outside of the ear of corn (two layers), the
entire length, covering the bottom and leaving the top open. Carefully slip the
ear of corn out of the foil-shaped container.
Do you think this
corn-shaped bowl will hold all the seeds on the ear of corn? Let’s find
out. Shell the kernels off the ear, putting them in the foil bowl you made.
Did all the kernels fit in the bowl? Shouldn’t there be extra
space left in the foil container from where the cob was? What happened? All
the seeds will not fit in the bowl, because of the air space between each
kernel. Nature arranged them tightly in neat rows to get as many seeds as
possible in a small space. |
Apply
The Numbers Game:
Have the children count the
number of seeds they shelled from the ear of corn.
If each corn plant
produces two ears, how many seeds would that plant produce?
If a bushel
of corn holds approximately 72,000 seeds, how many plants, at two ears per
plant, would it take to fill a bushel of corn?
What does it mean when
we say “Nature is very efficient?” How many seeds did it take to
produce all the seeds on the ear of corn?
Think of other examples from
your collection that show how efficient nature can be.
What do farmers
and gardeners do with all the seeds produced in their gardens and fields?
seeds are used for food for animals and people, in thousands of products,
saved for planting next year, research
When would you want to stop
plants from producing seeds? Read the example below.
Redroot pigweed is
a common weed found in farm fields and gardens. It can grow 2 to 4 feet tall.
The flowers don’t look like much, they are small and green, but are loaded
with seeds - up to 100,000 tiny black seeds per plant! This is why gardeners
and farmers hoe and cultivate to destroy the plants when they are small, before
they are able to produce so many seeds. |
Food for
Thought
When
an acorn falls from the tree, why doesn’t it begin to grow as soon as the
squirrel puts the acorn in the soil? Why won’t a pine seed grow when it
touches the soil in the fall?
This is a type of dormancy that nature
builds into some seeds. In order to germinate, the seeds need to be exposed to
cold temperatures for a few months. These seeds will be ready to sprout when
the weather warms up and spring rains moisten the soil.
What would
happen if an acorn sprouted and started to grow in October in Iowa? It would
die during the first winter because it will not be strong enough to withstand
the freezing cold weather.
Why won’t the seeds sprout inside
an apple or an orange? There is a chemical in the flesh or juice of the
fruit that keeps the seeds from sprouting inside the fruit. This prevents the
seeds from growing until there is soil and sunshine available for the young
plant. Ask them if they have ever seeds sprouted seeds inside a pumpkin when
they carved it for a Jack-o-lantern. Sometimes the chemical isn’t
effective in stopping early sprouting.) |
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