Lesson Title: Where the Wild Things (Rice) Are
Discipline Focus: Environmental Science
Grade level: 11th grade
Length of lesson: 1 day
Primary Author: Brian Kram Secondary Authors: Dan Costello, Brice Hansen
Stage 1 – Desired Results
Content Standard(s): (Minnesota)
The student will apply mathematics and models to analyze data and support conclusions
(I.B.3)
The student will identify possible sources of error and their effects on results. (I.B.4)
The student will recognize that science and technology are influenced by cultural
backgrounds and beliefs and by social needs, attitudes, values, and limitations. (I.C.5)
Understanding (s)/goals
Essential Question(s):
Students will understand:

What determines if manomin (wild
rice) grows in a given lake?
 How various stream properties
relate to one another

Does manomin grow in rivers and
 The relationship between abiotic
streams?
stream dynamics (depth, flow, etc)
and plant growth
Student objectives (outcomes):
Students will be able to:
 Take measurements of basic stream properties (turbidity, depth, flow speed,
temperature).
 Manipulate these measurements using mean, median, and mode to assess
accuracy.
 Assess how physical properties in a given environment effect manomin (wild rice)
growth.
Stage 2 – Assessment Evidence
Performance Task(s):
Other Evidence:
 Field work packet, which includes
 Student behavior and participation
data tables and follow up questions
during field work
(attached)
 Post-field classroom discussion of
concepts and measurements taken
Stage 3 – Learning Plan
Learning Activities:
1) Materials needed
Turbidity tube (see below)
Canoe with paddles
Paper and pen or pencil
Metered rope with anchor attached
Apple
Stopwatch
Thermometer
Wild Rice Lab packet
2) Timeline
1. The day before, we will discuss abiotic factors and brainstorm how they effect
plant growth.
2. We will head out to the lake with our canoes, divide into groups of three (time
depends on distance to study site).
3. I will demonstrate the proper way to make the required measurements (15
minutes).
4. Students will then be expected to make the necessary measurements and record
their data (with assistance from teacher) (2-3 hours total).
5. Bag lunch (30 minutes)
6. Travel back to classroom (dependent upon distance) and clean up supplies (15
minutes)
7. we will enter all of the group’s data into a single spreadsheet and discuss our
findings (45 minutes).
3) Developmental Activities
Guided discussion of abiotic factors:
Introduce the concept of abiotic factors. What factors will your class be able to
measure?
Show the students what factors you will be measuring; discuss what factors in
the lake or stream will effect your results.
Lesson tasks
Assemble students in middle of lake and demonstrate use of equipment
Turbidity and Depth– take 5 separate measurements spaced an adequate
distance apart and from shoreline
Flow- measure stream velocity over 10 m “reach” using apple, repeat
measurement at least once.
Temperature- take 2 measurements both at top of water column and near the
bottom. Measurements should be adequately spaced apart and from shoreline,
and at least 3 centimeters below water surface.
4) Closing activities
Complete lab packet calculations and questions
Compile class measurements into spreadsheet and discuss
Key questions for classroom discussion: Why is it important to take repeated
measurements during data collection? How reproducible are your
measurements? How much do abiotic factors vary across a lake? How do they
compare between lakes and streams? How do abiotic factors affect wild rice
growth?
Building a Turbidity Tube:
This device yields data for streams that is similar to a secchi
depth measurement in lakes. As for secchi measurements are
made in the shade with the sun to your back to make an
accurate and reproducible reading - the shadow of the
observer should be adequate. 1.Pour sample water into the
tube until the image at the bottom of the tube is no longer
visible when looking directly through the water column at the
image. Rotate the tube while looking down at the image to see
if the black and white areas of the decal are distinguishable.
2.Record this depth of water on your data sheet to the nearest
1 cm. Different individuals will get different values and all
should be recorded, not just the average. It is a good idea to
have the initials of the observer next to the value to be able
identify systematic errors. 3.If you see the image on the
bottom of the tube after filling it, simply record the depth as >
the depth of the tube. Then construct a longer tube, more
appropriate for your stream.
Information provided by:
Lake Access http://lakeaccess.org/russ/turbidity.htm
A program of The Natural Resources Research Institute,
University of Minnesota Duluth
WILD RICE LAB
Mânomin (Zizania palustris) requires specific environmental
conditions for growth. Today you will take a variety of
measurements to experimentally determine suitable growing
conditions for wild rice. You will do this by measuring the following
water characteristics: turbidity, depth, flow, and temperature.
Turbidity
Using a turbidity tube, measure the turbidity of 5 separate water samples.
Individual water samples must be taken at least 5 canoe lengths apart and
should be no less than 10 canoe lengths from the shoreline.
Record turbidity in units of distance and report this measurement in both
CENTIMETERS and INCHES. Hint: 2.54 centimeters = 1 inch
Calculate the mean, median, and mode of the turbidity measurements.
Turbidity
Site # 1
Turbidity
Site # 2
Turbidity
Site # 3
Turbidity
Site # 4
Turbidity
Site # 5
Mean
Median
Mode
Turbidity
(inches)
Turbidity
(centimeters)
Questions:
1) Which calculation provides the most meaningful information about
water turbidity in this situation- mean, median, or mode? Why?
2) What factors affect water turbidity?
Depth
Take 5 measurements of water depth; each measurement should
again be taken at least 5 canoe lengths apart and should be no less
than 10 canoe lengths from the shoreline.
Record depth and report this measurement in both METERS and FEET.
Calculate the mean of the depth measurements.
Depth Site #
1
Depth Site # 2
Depth Site # 3
Depth Site # 4
Depth Site # 5
Mean
Depth
(feet)
Depth
(meters)
Questions:
1) Why is it important that water levels in a wild rice bed remain
within a certain range? What effect could a sudden increase or
decrease in water levels have on the wild rice?
Flow
Mark 2 points, point A (“upstream”) and point B, exactly 10 meters
apart. At point A and in conjunction with a timer, a student lightly
throws an apple into the water at right angles to the shore. The
timer (standing at point B) determines how long it takes the apple to
reach directly in front of point B. A recorder takes down the times.
Repeat twice for a more reliable measurement.
Calculate the speed of water in the mânomin stand in METERS PER
SECOND and KILOMETERS PER HOUR. Calculate the average of the
measurements.
Measurement # 1
Measurement # 2
Average
Time to go from
point A to point B
Distance from point
A to point B
Water flow speed
(m/s)
Water flow speed
(km/hr)
Questions:
1) How does the flow of water at this stand compare to the speed of
moving water in the St. Louis River and Lake Superior (you will
need to research this)?
2) Do you think that water flow speed in this wild rice stand changes
much throughout the course of the year? Why or why not?
Water Temperature
Take 4 measurements of water temperature- 2 at the top of the
water column and 2 at the bottom. Each measurement should again
be taken at least 5 canoe lengths apart and should be no less than
10 canoe lengths from the shoreline. Surface measurements should
be taken with the temperature probe submerged 3 centimeters under
the water.
Report water temperatures in both degrees FAHRENHEIT and CELSIUS.
Hint: (°F-32) x (5/9)= °C
Degrees Fahrenheit (°F)
Degrees Celsius (°C)
Surface Temperature
#1
Surface Temperature
#2
Bottom Temperature
#1
Bottom Temperature
#2
Questions:
1) If you wanted to compare water temperatures in all of the wild rice
stands across North America, what additional variables would you
want to control in order to minimize error?
2) It is the middle of July, and weather forecasters have warned
gardeners to cover up their vegetables because there is going to be
a single night of frost (a freak occurrence). Would you, if it were
possible, need to cover up the wild rice crop? Why or why not?