North Dakota Department of Agriculture

This issue of the Ag Mag focuses on weeds. The
Ag Mag’s information and activities are geared
primarily toward the state’s third, fourth and
fifth graders. The Ag Mag is distributed three
times per year. Subscriptions are free, but if
you’re not on the mailing list or if you know
someone who wants to be added, contact the
North Dakota Department of Agriculture at
(800) 242-7535 or ndda@nd.gov.
The magazine also is on the Web at www.
ag.ndsu.edu/agmag/agmag.htm or through
the North Dakota Agriculture in the Classroom
website at www.ndaginclassroom.org.
This magazine is one of the N.D. Agriculture in
the Classroom Council activities that helps you
and other K-12 teachers integrate information
and activities about North Dakota agriculture
across your curriculum in science, math,
language arts, social studies and other classes.
It’s a supplemental resource rather than a
separate program.
Teacher’s Guide
Weeds grow in yards, gardens, fields and pastures; along roadsides;
and by rivers and lakes. They also grow in all shapes, sizes and
colors. Some people define a weed as any plant growing where it is
not wanted, such as a dandelion in a lawn, field bindweed in a wheat
field or musk thistle in a pasture.
Many students may think a dandelion is a flower. Dandelions are
considered a weed because they grow in yards, road ditches, fields
and many other areas where they are not wanted. Most people do not
like the little yellow weed growing in their lawn and will spray them
with chemical or dig them out of the ground to kill them.
Some weeds started out as useful plants. For example, purple
loosestrife was a beautifully striking purple-flowered garden plant
before it aggressively spread. Saltcedar was introduced to the U.S. to
reduce erosion along stream banks, but it then took over, displacing
native plants. Some corn kernels may drop to the ground during
harvest and grow the next year – when the field is planted to wheat.
Idea: Brainstorm weeds with students. Define weed. What weeds do
they already know?
If they don’t know the weed’s name, have them draw a picture of
what it looks like.
Idea: Have the students go outside and find as many different
weeds as they can. Have them draw a picture or write a descriptive
paragraph about the weed(s) they saw.
N.D. Agriculture in the
Classroom Mission
To cultivate an understanding of the
interrelationship of agriculture, the
environment and people by integrating
agriculture into K-12 education
Weeds,
weeds,
weeds!
North
Dakota
Ag
in the
Classroom
2
Answers to What is a Weed?
1. environmental
2. physical
3. wildlife
4. spread
Even though some weeds are pretty,
they’re harming a lawn, crop,
pasture or other vegetation. Those
weeds aren’t wanted there. Some
flowers, such as wild prairie rose
and wild sunflower, are considered
weeds when growing in an unwanted
location. Dandelions probably are
the best example for students.
Idea: Wildflower or Grass-Head
Babies Activity — Cut an 8- to 10-
inch portion of pantyhose, and fill
the toe with a couple tablespoons
of wildflower or grass seed mixture.
Add a mix of potting soil and wood
shavings. Tie off the bottom, and
have students create a nose and ears
using small rubber bands. Draw eyes
and a mouth. Place the ‘baby’ in a
Styrofoam cup, moisten it and set
the cup in a well-lit window. Water
regularly, and watch as it begins to
grow grassy or wildflower hair.
Idea: Review with students the basic
parts of most plants. Talk about
how weeds have adapted to their
environments. For example, many
perennial weeds have long
tap roots to grow deep to reach
water.
Noxious weeds are plants designated
by state or national agricultural
authorities as plants that are injurious
to agricultural or horticultural crops,
humans or livestock. Many times,
they are introduced into an area by
accident, but some are native plants.
Usually, they are plants that grow
aggressively, multiply quickly and
adversely affect desirable plants.
North Dakota has 11 weeds on the
state’s noxious weeds list.
North Dakota’s Noxious Weed Law
requires that landowners control
noxious weeds. Weed boards are
active in all of North Dakota’s 53
counties and in six cities (Bismarck,
Devils Lake, Dickinson, Fargo, Grand
Forks and Mandan). (Source: North
Dakota Department of Agriculture)
Idea: Discuss why students think it
might be a law to prohibit certain
weeds. Discuss, in general, how state
laws are made.
Idea: Ask your local weed control
officer or Extension agent to speak
to your class. Ask a farmer to tell the
students about how weeds affect his
crop fields and pastures. Ask him to
bring samples of weeds, including
noxious weeds, if possible.
Definitions:
Noxious – seriously harmful weeds
or pests, often legally designated by a
government entity
Eradicate – destroy completely down
to the roots
Bract – a modified or specialized
leaf growing just below the flower
or flower stalk. Bracts often bring
attention to small or pale flowers. The
poinsettia’s tiny yellow flowers are
surrounded by vivid red bracts.
Answers to What Weed Am I?
This is a very challenging exercise.
The goal is not for students to be able
to identify these weeds but rather
for them to use their critical thinking
skills to read the descriptions and find
the characteristics that make each
weed unique.
1. Leafy Spurge
2. Saltcedar
3. Musk Thistle
4. Purple Loosestrife
5. Absinth Wormwood
6. Dalmation Toadflax
7. Yellow Toadflax
8. Canada Thistle
9. Spotted Knapweed
10. Diffuse Knapweed
11. Russian Knapweed