Introduction- The presence of water in soil is vital to support plant and other soil organisms. Its presence impacts nutrient availability, pH, dissolved salts and minerals, and temperature. Many lab tests require the soil samples without water content, and it is important to properly prepare soil samples for lab analysis to accurately conduct these tests. Objective- To learn the proper method for preparing a soil sample for laboratory analysis To measure gravimetric water content of a soil sample Materials- Convection oven Insulated oven mitt Balance/Scale Crucible and lid Sharpie Plastic bag Activity- Water Measurement Tweezers Soil sample Mortar and pestle Calculator Soil sieve and pan 1. Heat oven to 350F) 2. Weigh a clean dry crucible and record weight. [A] 3. Prepare soil by breaking up large peds and removing roots with tweezers. 4. Fill crucible with prepared soil. Weigh soil and crucible and record weight. [B] 5. Place crucible with soil in oven and allow to dry for 4 hours. 6. After 4 hours, remove crucible and place on tared balance/scale. Record weight of crucible and dried soil. [C] 7. Calculate the soil moisture by following the formulae in the table:

A. Crucible wt. (g)	----------------
B. Crucible + wet soil wt. (g)
C. Crucible + dry soil wt. (g)
D. Wet soil wt. (B+A)
E. Dry soil wt. (C-A)
F. Moisture wt. (D-E)
G. Soil Moisture (%) = x (F)/(E)

Activity- Sample Preparation 8. After the dry sample has been weighed and measured, dump the contents of the crucible into the soil sieve and gently shake. Remove any rocks or non-soil debris caught in the top (10) screen. Be sure the sieve has the collection pan attached! 9. Dump any soil that does not pass through the top (10) screen into the mortar and grind with pestle. 10. Dump contents of mortar into the sieve and gently shake. 11. Repeat steps 8-10 until all soil passes through the 10 screen. 12. Label the plastic bag with your names, sample location, soil type, and the date. 13. Dump the prepared sample into the plastic bag and store for lab analysis later. 14. Clean all supplies with soap and water and store to dry.