UNIT
3: INSECT CONTROL
FACT: INTEGRATED
PEST MANAGEMENT (IPM) IS AN IMPORTANT WAY TO MANAGE INSECTS THAT ARE HARMFUL
TO CORN
LESSON 1: A
Beauty Pageant (Language Arts, Music, Dance, Art)*
LESSON 2: Weather
or Not to Act (Math, Science)*
LESSON 3: Prolegs,
Head Capsules & Warts (Science)*
LESSON 4: Give
Me an "I" "P" "M" (Science,
Social Studies)*
*All Lesson plans are adaptable for ALL ages!
ELIZABETH SEES A BAD SIDE TO HER FAVORITE CREATURES
When she was 7, Elizabeth held magical powers over insects. She directed
crickets to chirp at the same time. She cheered caterpillars to crawl
faster. She called fireflies to light her path in the dark.
She loved and cared for insects. She rescued spiders from the vacuum
cleaner. She buried moths hit by the front grill of the car. She flagged
anthills so no one would step on them.
She imagined herself to be as small as insects. She wanted to float
high above the trees on the back of a green lacewing. She dreamed of
roaring through the grass on the back of a technicolor beetle. She thought
it would be exciting to live inside a honeycomb.
She eagerly anticipated every spring, the time of year her friends,
the insects, filled the earth around her.
One particular spring morning, Elizabeth was chasing water striders
as they walked on the creek. She was stepping from stone to stone, invisibly
she thought, when she saw a pickup truck drive into the yard. It was
the man who was going to work for her mom's company.
"He's an entomologist," her mom had explained. "An entomologist studies
insects."
The man lifted something heavy from his truck. It looked like three
long light bulbs in a cage. Elizabeth watched him hang it behind the
garage, with a basket below it. Then she went back to her friends.
That night the light was turned on. It was PURPLE!! The whole yard
glowed in a mysterious light. "The insects are attracted to that kind
of light," said Elizabeth's mom.
In the morning the basket was filled with insects. Elizabeth had never
seen so many kinds in one place, at one time. She never imagined so
many flew at night. Why weren't they sleeping? Now they were captured!
She watched the entomologist, his name was Al, sort the insects, count
them, then write on a clipboard. He said he was monitoring the kinds
and numbers of insects so he could learn more about their life cycles.
He said he would do it all summer.
Elizabeth didn't understand it. She didn't like it either. She wanted
to warn all insects to stay away. She loved them. They were her friends.
She didn't want to lead them into a trap.
She ordered all the grasshoppers not to jump into the basket. She hummed
a danger signal to the bees, and blew magic messages into the air to
keep the dragonflies far away.
Then Al hung another trap. This one looked like a flying sandwich,
like two pieces of white bread with a space between. The bottom piece
was covered with something very sticky.
"It's a black cutworm trap," he explained. "There's a pheromone lure
inside. It smells like a female, so the males fly to it."
"Worms can't fly," Elizabeth said to herself. She had better things
to worry about than a sandwich in a tree that was supposed to catch
worms.
But the next morning, Al showed everyone what he had caught. Stuck
on the bottom were eight beautiful black moths! Their wings were two
to three inches across, their bodies covered with soft hairs.
"Looks like we had a significant flight last night. These moths came
up on the wind from the south. They're probably laying eggs in the soybean
stubble right now."
Elizabeth knew "soybean stubble" meant the leaves and stems left in
the field from last year's soybean crop. She was happy these moths visiting
from the south could find safety in her field. "Do they speak Spanish?"
she wondered.
And so the weeks went by-Elizabeth trying to wish the insects away,
but Al still catching and counting them every day.
Tractors came to the field by her house, and left. "Dave is planting
corn," her mom said, and showed Elizabeth how to find the seeds planted
two inches under the soil.
At first the seeds just sat there. Then it rained, and pretty soon
Elizabeth could see little green plants in rows in the field. Every
day the corn grew a little more, and the lines of green grew easier
to see.
Elizabeth loved to run in the field. Everywhere she looked there were
baby corn plants pushing small leaves out into the sun.
"My corn is growing!" She was so excited!
Then one day Al said it was time to check for cutworms. "There have
been enough Growing Degree Days (GDD) since the flight of moths into
our area. After the eggs are laid it takes a certain amount of heat
for them to hatch, and more heat for them to grow into worms that can
cause problems. The amount of heat needed is called "Growing Degree
Days."
Elizabeth and her mom walked through the field. Her mom called it "scouting."
They walked and walked. There was corn everywhere. They dug in the soil
by the roots, and in many places they found a worm. A cutworm!
They found a few worms that were already very big, about 1 ¬ inch long.
"They hatched earlier," explained Elizabeth's mom.
There was no corn left by those big worms.
The black cutworms had crawled down the row eating corn plants, one
after another, getting bigger and bigger as they ate. Sometimes the
plant was still lying where they'd cut it off. Sometimes it was still
standing, but there was a hole through the bottom of the stem, and it
was dying.
"Mom, QUICK! The worms are killing my corn. We have to stop them!"
Elizabeth didn't know insects could hurt anything so bad. She wanted
them to stop.
Then her mom explained that the farmer would put an insecticide on
the field that day to control the worms. She explained that sometimes
insects could be bad.
She explained that entomologists and farmers use traps to catch insects
to predict if they will be a problem. They monitor weather and temperatures
to predict when problems will begin. But after their prediction, someone
still must go to the field to see if there is a problem. No one wants
to spray an insecticide unless they need to. But if there is a problem
they need to take care of it fast, before their crop is destroyed!
Elizabeth had a different feeling about insects after that day. She
still loved them. But she'd seen the harm they could do. She decided
she wanted to learn more about them, the good ones and the harmful ones.
Maybe if she learned enough about the different worlds of insects and
people, she could use her magic powers to help them both.