To be able to classify soils, one 1st needs to develop soil identification skills. These include ability to identify soil horizons and parent material types. Soil horizon identification is important to decide on the diagnostic soil horizon, while parent material identification helps with understanding of soil properties and its response to management practices. Both identification of soil horizons and parent materials are based on visual interpretation skills, which can be developed by viewing and reviewing numerous soil pits in the field and/or monolith photographs.

Practice questions listed below address (1) identification of parent material or (2) identification of soil horizons.

By clicking on the links provided below in specific questions, you will be taken to a page with monolith’s photo and description. Enlarge the photo and carefully observe it. You might want to refer back to the monolith description.

Questions re. identification of parent material

NOTE – to review different types of soil parent material visit our website entitled “Soil Formation and Parent Material” in which you will find short video clips of all major types of parent materials. Please go to the Parent Material web page.

1. In the monolith no. 7-49, the parent material is identified as lacustrine. What properties are typical for this type of parent material? Can you observe these properties on the photo?
2. Monoliths no. 1-11, 4-01, and 5-05 also have lacustrine parent material. Take a close look at the C horizons of these 3 monoliths and compare them to the C horizon of the monolith no. 7-49. Do you see the most typical property of the lacustrine parent material in the monoliths no. 1-11, 4-01, and 5-05? Is the property in question more or less pronounced in these three monoliths than in monolith no. 7-49?
3. In the monolith no. 7-40, the parent material is identified as glacial till. What properties are typical for this type of parent material? Can you observe these properties on the photo?
4. In the monolith no. 8-02, the parent material is identified as colluvium. What properties are typical for this type of parent material? Can you observe these properties on the photo?
5. In the monolith no. 1-01, the parent material is identified as glacio-fluvial. What properties are typical for this type of parent material? Can you observe these properties on the photo?

Questions re. identification of soil horizons

NOTE – to review the most typical properties of 10 soil orders (the broadest, most general classification category) and their diagnostic horizons visit our website entitled “Soil Classification: Canadian Soil Orders”. The website features 10 short video clips illustrating characteristics of 10 soil orders.

1. In the monolith no. 9-01, locate the Bnt horizon. What soil property (or properties) makes this horizon a Bnt?
2. In the monolith no. 4-01, locate the Btg horizon. What soil property (or properties) makes this horizon a Btg?
3. In the monolith no. 7-39, would you characterize the texture of Bf1 and Bf2 horizons as fine or coarse? Is the observed texture typical for a Bf horizon?
4. Monolith no. 7-06 has a prominent Bf horizon (actually there are Bf1, Bf2, and Bf3) characterized by a reddish color. What soil process is responsible for this red color of the Bf horizon?
5. In the monolith no. 8-03 , no B horizon has been identified. Can this be the case? If yes, please explain what events could have prevented development of the B horizon.
6. In the monolith no. 5-28, identify the types of soil structure present in A and B horizons. What soil formation process has been responsible for the change of structure in this Luvisolic soil?
7. Compare monolith no. 5-16 to monolith no. 5-28 (mentioned above in question #6). Both soils are classified as Orhic Gray Luvisol and in both of them there is a change in soil structure from horizon to horizon. Is the change in soil structure equally noticeable in both monoliths?
8. Monolith no. 2-11 is classified as a Chernozem. What is the diagnostic horizon of a Chernozem? Locate this horizon on the profile. What clues did you use to locate it?
9. Locate the B horizon of monolith no. 1-04. In your opinion, is it more likely to be a:
   • Bf
   • Bg
   • Bm
   • Bt

Justify your answer.