Growing the Future by Teaching Children in the Gardens
www.GrannysGardenSchool.org / 20 Miamiview Lane, Loveland, OH 45140 / 513-324-2873
Are Plant Parts the Same in Different Weed Types?
Grade Three
Lesson Summary
When to use this lesson
Use this activity when weeding is required in your garden.
Objective
Students collect data about two weed types to understand differences in the same plant
part.
Materials
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



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Worksheet for each student
A set of weed pictures for each team from the barn
A clipboard for each student
A pencil for each student
A bucket for each team of students
Bring taproot and fibrous roots examples
Bring netted and parallel veins examples
Estimated Duration
30 minutes
Ohio Learning Standards Connections
Life Science
Individuals of the same kind differ in their traits and sometimes the differences give individuals an
advantage in surviving and reproducing.
 Plants and animals have physical features that are associated with the environments where
they live.
 Plants and animals have certain physical or behavioral characteristics that improve their
chances of surviving in particular environments.
 Individuals of the same kind have different characteristics that they have inherited.
Sometimes these different characteristics give individuals an advantage in surviving and
reproducing.
About Weeds

Explain that the class will remove weeds from their garden areas to compare plant parts.

What is a weed? A weed is a plant that is growing where we do not want it.

Are weeds needed in nature? The flowers of some weeds are nectar sources. Many weeds
are edible for people and contain vitamins and minerals (some examples - dandelion,
purslane, wood sorrel). Some weeds are used for medicine. Plantain has antibacterial
properties and has been used to treat sore throats, colds, and the flu. Some weeds have
been developed by man into a new, more useful or acceptable plant – like a kind of wild
grass into the corn plant we know today.
Revised 1/16 © 2014 - 2016 Granny's Garden School, Inc. We encourage you to use these lesson plans and change
them to fit your specific needs. We ask only that you credit Granny's Garden School as your source.
Page 1

Why do we remove weeds? We want to prevent them from spreading, to remove them
before seeds form, to give the plants we want the space, food, and water they need
without weeds crowding them and competing for resources.

Explain the activity. Students work in teams in an assigned a location to pull weeds. Each
team will have its own bucket to collect pulled weeds. After the allotted weeding time, the
students gather in their teams to sort the weeds and complete a worksheet. Each student
records data on his or her own worksheet, but works together with his or her group.

Explain the two main types of weeds they will pull. Broadleaf weeds have wide leaves (like
the dandelion), and grass-like weeds have leaves that are narrow like grass (like the crab
grass). Show examples.

Examine the two main types of roots. Roots structures can be fibrous or a taproot. Fibrous
roots spread and look tangled (crab grass, grass). A taproot is a main thick stem that grows
downward with small roots branching off (dandelion, carrot). Show examples. The pictures
will help them if they are unsure of the root type of the weeds they pull. What are the
advantages and disadvantages for each type of root? Fibrous are shallower and are
affected more quickly in dry conditions. It may be harder to pull all of the roots to remove
the entire plant. Taproots are thicker to hold more water in a dry spell and some long
taproots can reach down more deeply to find water. Once you have the taproot, the plant
can’t regrow, but the taproot is hard to get if it is long.

Examine the two types of veins. Parallel veins run in the same direction and do not touch.
Netted veins are branching veins. What are the advantages to the vein types in the
example weeds? It’s all about the most efficient way to get water distributed in the leaf.
The long and narrow blade is suited to long, parallel veins. Wide, irregular leaf shapes need
netted veins to reach through the leaf shape to transport water.

Instruct students to pull weeds with their fingers as close to the soil as possible. Many weeds
have long roots and spreading roots, which all need to be removed as completely as
possible to help prevent them from growing again from the roots. Their fingers should touch
the soil when they pull. Plus, the roots are needed to complete the worksheet. Only weeds
with roots can be used for collecting data in the table.

Divide the students into teams. Give each team a set of pictures to help them sort weeds
and a bucket to collect weeds. The pictures in the lesson are grouped by late summer
weeds and spring weeds.

Give students about 10 minutes to pull weeds in an area you select.

Gather the teams to discuss the worksheet. Review the column headings of the table.
Explain that the Venn diagram is a type of graph to summarize collected information. Ask
students what information is needed on the graph – a title, labels. Decide on a title and
labels as a group to get them started. Ask students how the sections of the Venn diagram
will be completed using the weed traits on the worksheet. Those weed traits that apply only
to broadleaf weeds they collected will be written in the broadleaf section of the Venn
diagram. Those that apply only to grass-like weeds they collected will be written in the grasslike section. Those that apply to both broadleaf and grass-like weeds will be written in the
center, shared link.

They should use a random sampling of at least 10 weeds. One student pulls out the first
weed. As a group, decide if it is broadleaf or grass-like, and then put a tally in each box that
applies to their weed. Do one weed example together.
Recording Data and Completing the Graph
Revised 1/16 © 2014 - 2016 Granny's Garden School, Inc. We encourage you to use these lesson plans and change
them to fit your specific needs. We ask only that you credit Granny's Garden School as your source.
Page 2

Leave time to review the following questions. What traits are common to our sample of
broadleaf and grass-like weeds? What traits are seen only in the sample of broadleaf
weeds? Only in the sample of grass-like weeds? Which method (table or graph) do you
prefer to use to answer these kinds of questions or to share your findings with others? Did all
weeds have seeds and flowers? They do, but may not be on the plants at the same time
depending on the stage of the weeds life cycle. Was it easy to spot the taproots? Did some
weeds have taproots and many fibrous roots?

How could we improve our reporting? We could repeat the study. We could collect
additional samples of a weed if our observations were conflicting. We could consolidate our
team findings into class findings.

At the end of the session, weeds should be disposed of in the compost area (not the leaf
mold) in the Hill Gardens.
Example to title and label Venn diagram
Title: Comparing Broadleaf and Grass-Like Weeds
Broadleaf weeds
Grass-like weeds
Revised 1/16 © 2014 - 2016 Granny's Garden School, Inc. We encourage you to use these lesson plans and change
them to fit your specific needs. We ask only that you credit Granny's Garden School as your source.
Page 3
Growing the Future by Teaching Children in the Gardens
www.GrannysGardenSchool.org / 20 Miamiview Lane, Loveland, OH 45140 / 513-324-2873
Are Plant Parts the Same in Different Weed Types – Grade Three
Name: ____________________________________________
Weed
Category
Broadleaf
weeds
Grass-like
weeds
Taproot
Fibrous
roots
Parallel
veins
Netted
Veins
Seeds
Flower
Using your knowledge of weeds and your table, create a Venn diagram to classify these
characteristics of broadleaf and grass-like weeds:
taproot
netted veins
seeds
fibrous roots
parallel veins
flowers
_____________________________________________________________________________
__________________________________________________
_________________________________________________
In science, we learn about physical traits that help a plant’s survival. Today we pulled weeds in
our garden to compare plant parts in different weed categories. Ask your student how the
differences in plant parts are beneficial or detrimental. Email [email protected]
to join us for our next gardening experience!
Revised 1/16 © 2014 - 2016 Granny's Garden School, Inc. We encourage you to use these lesson plans and change
them to fit your specific needs. We ask only that you credit Granny's Garden School as your source.
Page 4
Weeds we find in late summer and fall.
Purslane – broadleaf, shallow taproot with secondary fibrous roots, netted
veins
Dandelion – broadleaf, taproot, netted veins
Clover – broadleaf, fibrous roots, netted veins
Cross, Lelia. clover_in_bloom.jpg. April, 2012. Pics4Learning. 23 Jul 2013
<http://pics.tech4learning.com>
Crab Grass – grass-like, fibrous roots, parallel veins
Arthur, Richard. Crabgrass.jpg. July 2006. Wikipedia. 23 Jul 2013 <
http://en.wikipedia.org/wiki/File:Crabgrass.JPG>
Wood sorrel – broadleaf, small taproot with side fibrous roots, netted veins
Hazen, Bob. wood_sorrel6626.jpg. July 2009. Pics4Learning. 23 Jul 2013
<http://pics.tech4learning.com>
Broadleaf plantain – broadleaf, taproot with fibrous roots, netted veins
Spurge – broadleaf, small taproot with side fibrous roots, netted veins
Hardyplants. Chamaesyce.jpg. February 2009. Wikipedia. 23Jul 2013 <
http://en.wikipedia.org/wiki/File:Chamaesyce.jpg>
Nutgrass – grass-like, rhizomes with fibrous roots, parallel veins
Rickjpelleg. Nutgrass Cyperus rotundus02.jpg. December 2005.
Wikipedia. 3 Jul 2013
<http://en.wikipedia.org/wiki/File:Nutgrass_Cyperus_rotundus02.jpg>
Carpetweed – broadleaf, taproot, netted veins
Eric in SF. Mollugo verticillata.jpg. 8 July 2012. Wikimedia Commons. 8 Feb
2015 < http://commons.wikimedia.org/wiki/File:Mollugo_verticillata.jpg>
Thistle – broadleaf, taproot, netted veins
Lewis Collard. Mean-looking thistle.jpeg 29 Aug 2008. Wikimedia
Commons. 19 Feb 2015 <http://commons.wikimedia.org/wiki/File:Meanlooking_thistle.jpeg>
Lamb’s quarters – broadleaf, shallow taproot with fibrous side roots,
netted veins
6th Happiness. 6H-Lambs-quarter.jpg 15 June 2009. Wikimedia
Commons. 19 Feb 2015 <http://commons.wikimedia.org/wiki/File:6HLambs-quarter.jpg>
Weeds we find in early spring.
Chickweed – broadleaf, mostly fibrous with very narrow shallow taproot,
netted veins
Dandelion – broadleaf, taproot, netted veins
Hugo.arg. StellariaMedia001.JPG. 20 Jun2007. Wikimedia Commons. 19
Feb 2015
<http://commons.wikimedia.org/wiki/File:StellariaMedia001.JPG>
Deadnettle, Henbit – broadleaf, taproot, netted veins
Masaki Ikeda. Lamium amplexicaule 0904.jpg. 8 Apr 2009. Wikimedia
Commons. 19 Feb 2015
p://commons.wikimedia.org/wiki/File:Lamium_amplexicaule_0904.jpg>
Purple dead nettle – broadleaf, taproot, netted veins
AnemoneProjectors. Red Dead-nettle (Lamium purpureum).jpg. 6 Apr
2011. Wikimedia Commons. 19 Feb 2015
<http://commons.wikimedia.org/wiki/File:Red_Deadnettle_(Lamium_purpureum).jpg>
Quackgrass – grass-like, rhizomes with fibrous roots, parallel veins
What Weeds Can Tell You About Your Garden. BCFarmsandFood.com
© 2010. Photo used by permission.
http://bcfarmsandfood.com/what-weeds-can-tell-you-about-yourgarden/
Speedwell, purslane – broadleaf, taproot, netted veins
Robert Flogaus-Faust. Veronica peregrina2 RF.jpg. 3 May 2008.
Wikimedia Commons. 19 Feb 2015
<http://commons.wikimedia.org/wiki/File:Veronica_peregrina2_RF.jpg>
Speedwell, corn – broadleaf, taproot, netted veins
Olivier Prichard. Veronica arvensis saint-fuscien 80 19052007 10.jpg. 19
May 2007. Wikimedia Commons. 19 Feb 2015 <
http://commons.wikimedia.org/wiki/File:Veronica_arvensis_saintfuscien_80_19052007_10.jpg>
Wild garlic – grass-like, bulb with fibrous roots, parallel veins, tubular leaves
Conrad Nutschan. Allium vineale Pillnitz.jpg. 3Apr 2007. Wikimedia
Commons. 20 Feb 2015
<http://commons.wikimedia.org/wiki/File:Allium_vineale_Pillnitz.jpg>
Wild onion – grass-like, bulb with fibrous roots, parallel veins, flat leaves
George F. Mayfield. Allium canadense WILD ONION.jpg. 13 Jun 2006.
Wikimedia Commons. 20 Feb 2015
<http://commons.wikimedia.org/wiki/File:Allium_canadense_WILD_ONION.jpg>