Soils & Soil Physical Properties
Unit 2.1 | Part 2 – 23
Demonstration 1: Soil Texture Determination
for the instructor
INSTRUCTOR OVERVIEW
The following demonstration
outline covers the resources and
skills used to determine the texture
of a given soil sample by feel and
to determine the approximate
percentages of sand, silt, and clay
in that sample. First demonstrate
how to use the Soil Texture Decision
Chart to identify the texture of
a given sample. Following this,
give students the opportunity
to identify the approximate soil
textural classification of several
additional soil samples. The Soil
Texture Triangle is used to help
students determine the approximate
percent of sand, silt, and clay in
their samples. The Soil Texture
Descriptions are included to
help confirm the accuracy of
the determination by providing
descriptions of how the soil feels and
performs under several tests.
MATERIALS
- Multiple samples of different kinds of soil textures
- Handouts (see below)
- The Soil Texture Decision Chart: How soil texture is
determined - The Soil Texture Triangle: The percentatges of sand, silt,
and clay in each textural classification - The Soil Texture Descriptions: How the soil feels and
performs under several tests
DEMONSTRATION TIME
About 1 hour
DEMONSTRATION OUTLINE
A. Demonstrate how to determine the soil texture of a
given sample by feel using the Soil Texture Decision
Chart (next page)
B. Determine the percentage of sand, silt, and clay in the
soil sample using the Soil Texture Triangle (page 2-25)
C. Use the Soil Texture Descriptions (pages 2-26–27) to
confirm the accuracy of the textural determination
D. Students practice determining soil texture following
the same steps
E. Once a texture has been determined, describe/discuss
the characteristics of each of the soils:
- Drainage
- Water availability
- Cation exchange capacity (CEC)
- How it may be improved using organic farming practices
Instructor’s Demonstration 1: Soil Texture Determination