Take your invertebrate sample at your benchmark, approaching the sample site from downstream

You can easily mark your sample area by using flag tape, or even some brightly painted rocks.

Thoroughly scrub the rocks within the sample area

Use a small gardening claw to scratch the bottom of the stream

Empty the contents of the "D" net into a pail, rinsing it with another pail of water

Separate the invertebrates into the ice cube trays, and use the invertebrate key to identify species