Sky
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SEEDS
small
ABOVE
Earth
BELOW
FUN THINGS TO DO
thing
All living things have found a way for reproducing members of their own species. Most plants reproduce by seed.
Seeds come in a wide variety of sizes, shapes and colors. The smallest seed comes from a tropical rainforest
orchid too small for the unaided human eye to see. The largest seed, from the Coco de mer palm tree, can weigh
up to 40 pounds. Small or large, all seeds contain just the right materials and information to grow a new plant of
the same type as its parent.
Flowers are Seed Factories
In flowering plants, seeds are produced by flowers. The
bumblebee visiting its favorite flower for a drink of sweet
nectar, or perhaps a gentle breeze blowing across the flower
helps move pollen from the anthers of a flower to the stigma
of the same or another flower. The pollen then grows a tube
down the style to where it fuses with the ovule in a process
called fertilization. The fertilized ovule becomes a seed and
the ovary becomes the fruit. (See diagram)
What’s Inside a Seed?
Break open a lima bean seed that has been soaked in water
overnight and you will see the three basic parts of a seed. The outside of the seed is covered by a seed coat, which
protects the seed. Look carefully inside the seed and you will find the embryo, or the earliest stage of a young
plant’s growth. You may be able to see what look like tiny leaves, a small stem, and what will become the first root.
The main part of the seed is the endosperm or cotyledon, which serves as a lunch box full of proteins, fats, and
starches and for the young seed until it can make its own leaves and its
own food.
A Place of One’s Own
Seeds need to find a place to grown away from their parents plants.
If they remain too close, the bigger. stronger parents will block the
sunlight and use all the water. Fortunetly the parent plants epuip
each seed with a way to make the journey, called dissemination. Here
are some of the ways seeds travel.
• By Wind: If you have ever blown on a dandelion seed head and watched the
tiny seeds fly away on their parachutes, you have helped spread seeds. Other
windblown seeds include milkweed and maple seeds. Tiny wind-born seeds can be carried many miles on a
windy day.
•By Water: Coconuts have a special outer seed coat that allows them to float. They may drift for several months and travel
thousands of miles before reaching dry land. Trees such as willow, cottonwood, and sycamore, which grow along stream banks,
drop many of their fluffy seeds into the water, where the fluff keeps them afloat on the current that carries the seeds to new
sites.
•Inside Animals: Seeds encased in tasty fruit, such as berries, are eaten by birds and other animals and deposited
elsewhere in fertilized packages in the animals’ droppings.
•Outside Animals: Sticky seeds like mistletoe or seeds with barbs and hooks such as burdock burrs catch on fur or skin
and travel with the animals to new locations where they eventually fall off.
•Planted by Animals: Some seeds such as acorns are carried off and planted by squirrels, possibly to be eaten later. Not
all are eaten. Spring flowers put a small food package on the outside of their seed, which ants feed to their young. The ants
drag the seed down into the ant hill, remove the food package and discard the undamaged seed, unintentionally planting it.
•Thrown Away: Some seed pods explode, throwing their seed far from the parent plant. The Witch Hazel, a plant native to
Connecticut, can hurl its seeds 20 to 30 feet away!
Wake up Seeds!
When a seed begins to grow it is said to germinate. Often seeds wait to germinate until conditions are just right.
They go into a state of dormancy, or inactivity, where the seed is alive but does not grow. Warm sunshine, spring
rains and longer days awaken many seeds from their winter dormancy. During germination, the seed swells as it
absorbs water and begins to use the food stored in the cotyledons. The seed coat splits
and the first root, called a radical, will grow downward into the soil to help provide water and
nutrients to the growing seedling. The first pale leaves appear on the shoot (hypocotyl),
which grows above the soil. As the leaves begin to use sunlight for making food, they develop
a chemical called chlorophyll which turns the leaves green. Chlorophyll allows the plants
to make sugar from sunlight, water, and carbon dioxide (plants LOVE carbon dioxide!) in a
process called photosynthesis. As the plants grow stronger, flowers will develop and the
process of reproduction will begin again.
Lots of the fruits and vegetables we eat are seeds or contain seeds.
See how many different seeds you can find in these foods. Compare
seed sizes and colors. Which fruit or vegetable has the biggest or
smallest seeds?
Find an old, fuzzy, worn-out sock
that will fit over your shoe. Then
walk around outside in an area
where plants are growing or in a
field full of weeds. Take the sock
off and examine the kinds of
seeds that are stuck to the sock.
Want to see what might grow
from those seeds? Plant your
sock! Here’s how:
•Line a shoebox with a garbage
bag or plastic wrap.
•Fill the shoebox with potting soil. •Cut a slit down the side of your sock and flatten your sock on top of
the soil with the seed side facing up.
•Cover the sock with a thin layer of soil and then water it. •Put the shoebox in a sunny place and keep the soil moist. In a week or
so the seeds should begin to sprout.
IN THE NEWS
Check the Courant’s archives about recent articles relating to seeds.
Monsanto, the court and the seeds of dissent: Should Monsanto, or any
corporation, have rights to a self-replicating natural product?
http://www.courant.com/health/la-oe-kimbrell-monsanto-supreme-court-seed-20130219,0,1222212.story
“The Seeds”
http://www.courant.com/community/new-britain/hc-the-seeds-20120307,0,742791.photogallery
Lawn Care Tips For Connecticut Homeowners
http://www.courant.com/features/home-garden/hc-lawn-care-connecticut-20120420,0,7345815.story
READER SUBMITTED:
The Menunkatuck Audubon Society Announces Its Spring Plant Sale for The Birds
http://www.courant.com/community/hcrs-71585hc-middletownshoreline-20130227,0,7932275.story
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Fall 2013
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