Soil Lab
STATION 1 – Sand Soil Shake Down
Place a 100 ml scoop of dried soil from sample bucket 1 into the top sieve (labeled 1: Gravel). Place the
lid onto the stack of sieves and begin shaking. Try not to squeeze the sieve cups together, they become
very difficult to take apart. Shake for about 5 minutes. Carefully un-stack the cups and estimate the
amount of sediment in each cup.
________ % Course Sand (#3)
_______ % Fine Sand (#4)
________ % Silt/Clay (#5)
STATION 2 – Soil texture by the numbers (use the Soil Triangle worksheet)
Sample 1 soil type ______________________
Sample 2 soil type _____________________
Sample 3 soil type ________________________
STATION 3 – Soil texture by feel (use the Soil Texture by Feel worksheet)
Sample 1 soil type ______________________
Sample 2 soil type ____________________
Sample 3 soil type ________________________
Feet from start
of transect
0
20
40
60
80
100
Dry
Dry
Dry
Dry
Dry
Dry
Damp
Damp
Damp
Damp
Damp
Damp
Saturated
Saturated
Saturated
Saturated
Saturated
Saturated
Gritty
Gritty
Gritty
Gritty
Gritty
Gritty
Velvety
Velvety
Velvety
Velvety
Velvety
Velvety
Sticky
Sticky
Sticky
Sticky
Sticky
Sticky
Soil pH
Soil
Temperature
Soil Color
Water Content
Soil Texture
A soil texture triangle is used to classify the texture class of a soil. The sides of
the soil texture triangle are scaled for the percentages of sand, silt, and clay.
Clay percentages are read from left to right across the triangle (dashed lines).
Silt is read from the upper right to lower left (light, dotted lines). Sand from
lower right towards the upper left portion of the triangle (bold, solid lines). The
boundaries of the soil texture classes are highlighted in blue. The intersection
of the three sizes on the triangle give the texture class. For instance, if you
have a soil with 20% clay, 60% silt, and 20% sand it falls in the "silt loam"
class.
Use the triangle to identify the soil types at station 2.
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