FIELD TRIP: Cooley Middle School
Names:_______________________
Date: _____________
Today you will learn how to gather a soil sample and how to analyze its contents.
Materials:
Procedure: Using the appropriate materials, gather soil samples from the location assigned
from your teacher.
1. Put the soil sample (approximately two cups of soil) into a plastic bag.
2. Answer the following questions:
a. Observe where you are standing at the creek.
b. Does the creek flow in a straight line or does it curve?
c. Do you notice any erosion?
d. What type of erosion is it? ________________.
e. What has caused the erosion?_______________________________________________.
3. Return to your classroom when given permission by your teacher.
4. Put the soil on the pie tin. Use a magnifying glass to look at the grains of the soil. Record the size of the average grain: ______________. Do you think that it is clay? Silt? Sand? ________________________.
5. Weigh the paper cup that you will be using later. Record the weight: _________. Now pour 1/2 cup of soil into the cup. Record the weight of the soil and the cup: ________. Now pour 1/4 cup of water into the cup. Record the total weight: _________. Set the cup aside and cover with a plastic baggie. Do not mix!
6. Now pour 3/4 cup of water into the pie tin with the soil. Use a stirring stick to mix the soil and water together, so that it looks like a paste.
7. Make some notes on your soil paste. What is the texture like? Was it easy to mix or difficult? ______________________________________________________________________________.
8. Now measure the pH of your soil. Record the pH results: ______. Is your soil basic, neutral, or acidic? ____________________________. Does your soil have H+ (hydrogen) ions or OH- (hydroxide), or perhaps neither? ______________________________________________.
8. What color is your soil? _______________________________.
9. Based on what you learned previously, what soil horizon do you think your soil sample is from? ___________________________. Why? _______________________________________.
10. Now pretend that your soil sample is modeling clay. If it is hard to press together or shape, then it
is most likely clay. If it is easy to manipulate then your sample has more silt in it. If the grain size is
large and it is also easy to manipulate then there may be sand in your sample. You be the judge and
try to determine what percentages of clay, sand, and silt make up your sample.
Clay %: _________ Silt %: __________ Sand %: ____________.
Results Part One: Now consolidate the results of your tests:
pH of soil sample: _____ Color of sample: ________________________
Grain size of sample: _____________ Malleability of sample: ____________________
Soil horizon: _____________________ Percentages of clay: ______ silt: ______ sand: ______
PART II (to be completed following day)
Take the cup that you set aside yesterday and pour off the water into another cup. Subtract the weight of the paper cup that you recorded yesterday and record the weight of the cup and the soil: _________ and of the cup and the water: __________.
Results:
Record the following information below:
| Group # | Percentages of clay, silt, and sand: | Grain size of soil sample: | Soil horizon of sample: | Soil pH: | Weight of saturated soil: (Wgt. of soil - wgt. of paper cup) |
| Group 1: | |||||
| Group 2: | |||||
| Group 3: | |||||
| Group 4: | |||||
| Group 5: | |||||
| Group 6: | |||||
| Group 7: |
Conclusion:
Based on your results, describe your soil sample and the elements that define it. If your soil sample was
easy to mold, why was this so? Why do you think that your sample is the color that it is? Was your sample
close to the creek or farther away? How did this affect your pH? How did the particle size of your sample
affect the amount of water that it absorbed?