Soil sample processing: Sieving

• Weigh and record the whole dried soil sample to 0.1 g. • Mix the dry sample thoroughly while still on the drying tray. Spread the sample on a plastic sheet. Using a rolling pin, crush the sample to pass through a 2 mm sieve as you sieve and place in a separate pile (the coarse fraction). • Place whatever remains on the sieve back onto the plastic sheet and crush again gently. Then pass again through the 2 mm sieve. Make sure that all soil materials are crushed, but do not attempt to crush gravel and rocks. • Throw anything that now remains on the sieve into the coarse fraction pile. • The whole sample should be processed and no material should be discarded. You will remain with two fractions