Soil Report

This week in Sustainable Agriculture we completed a soil report. Day 1 of our report, each bed group received a cup and filled it to the top with a fresh soil sample from their assigned bed, using trowels to avoid tampering and interference. Once all students had their samples taken, we returned to the classroom to assess the composition. We added 20 mL of the soil sample to a 100 mL graduated cylinder and filled the rest with water. Students then covered the graduated cylinder in plastic making a tight seal, placing a hand over the top, and by inverting and shaking the cylinder, mixed the solution well for a few minutes. The graduated cylinders were then left in the classroom undisturbed for two days to let the contents settle out. Using the remaining soil, we executed a texture (feel/squeeze) test by holding a small clump of soil in our hands. Using an eyedropper, we added water to form a ball. 10-15 extra drops of water were then added to create a paste to determine if the soil felt grainy or smooth.

Day 2 of the soil report, we retrieved our graduated cylinders. Once the material in the cylinder had settled out, lines dividing sand, silt, and clay columns (in order from bottom to top) became visible. We then added up the volume of each column and recorded the total volume of the graduated cylinder. Once we had calculated the percent of sand, silt, and clay in the soil sample, we used a textural triangle to determine the texture of the soil. This was the first lab we have done in Sustainable Agriculture this year. Overall this experience was a very informative, hands on activity that taught us a lot about soil composition and how we can maximize plant growth by growing healthy soil.  
Drew J