 Hello, I am Mick and today we will look at the soil biological activity by looking at what earthworms are present and how many in our sites. However, earthworms are not in all ecosystems, so consider using other proxy or indicator species that suit your situation. Earthworms create channels that help with water infiltration and aeration in the soil. To observe the earthworms, we will need 2 liters of water, a hand trowel, a jar or container where worms can be collected and a mustard solution. The solution is made with 2 tablespoons of mustard powder mixed with 2 liters of water. Then we select one sample site per zone we are studying. We label this point with numbers both physically and on our site map. Then we measure a 30x30 cm square plot. We should avoid sampling where earthworm populations might be affected, for example mulched areas or compost piles. And we dig down 30 cm with a hand trowel, so we minimize damage to the earthworms. We count the number of earthworms against the pale-colored backgrounds to help locating them. Then we add mustard solution to the hole and wait for deep burrowing earthworms to appear. This usually takes around 5 minutes. Finally, we count the number of deep burrowing earthworms and add this amount to the surface earthworms. We record the yearly counts for each of the studied areas. We then count the amount of deep burrowing earthworms and we sum with the former to get a total amount of earthworms present in our sampling location. We record the counts every year for each of the sites we want to study in our datasheet. Before we leave, we rinse the earthworms in water and return them to the soil.