How does farming change soil quality compared to an untouched forest? You collect surface samples from three sites. One is a forest. One is a conventionally farmed field. One is a field treated with compost. In the field you observe structure and color. You check texture and earthworm activity. Back at the lab, you dry and sieve each sample. Then you test pH with a calibrated pen. A soil testing kit measures nitrogen and phosphorus. You also test for potassium. The forested soil had the darkest color and the most earthworms. The conventionally farmed soil was lighter and had surface crusting. It showed higher nitrogen from added fertilizer.