Procedure
Three methods are suggested here. Any one of these may be followed.
Method I
(i) Collect about 300–500g of soil from two different locations. Label them as sample A and B.
(ii) Dry the samples in an oven, or stove or in sun to remove the soil moisture (capillary and
bound water).
(iii) Select the 3 sieves of different mesh sizes (2mm, 0.05mm and 0.002mm). Arrange them in
a collecting chamber as shown in Fig. 15.2.
(iv) Place 200g of the soil in the Ist sieve (sieve of 2mm mesh) and close the lid. To sieve the soil,
shake the set manually for 5–10 minutes and collect the three soil fractions.
(v) Weigh the soil fractions viz-sand, silt and clay
collected in the 3 compartments
Wt of soil sample taken – .........g
Wt of sand fraction – .........g
Wt of silt fraction – .........g
Wt of clay fraction – .........g
The weight of three fractions should be equal to the
total weight of sample taken for analysis.
Calculate the percentages of the various soil fractions
and tabulate:
Calculate the percentages of sand, silt and clay
fractions.
Use the textural triangle now. Note that the three
sides of the textural triangle represent 0 to 100% of sand,
silt and clay respectively. Note that (i) the percentage
lines for clay run paralled to the base line of sand
the precentage lines of silt run parallel to the clay side of the triangle and, (iii)
perentage lines of sand run parallel to the silt silde of the triangle. In reading
the textural triangle, any two particle fractions will locate the textural class at
the point where these two intersect.

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