Earthworm sampling

When assessing differences in density and diversity of soil invertebrates, earthworms are often quantified separately from other macroinvertebrates.


  • Spade (straight-bladed shovel)
  • Tarp
  • Cooler containing:
    • Sample jars filled with 70% ethanol
    • Sharpie for labeling jars
  • Stereo microscope (dissecting microscope)
  • Field notebook for recording data


  1. Choose the first sample location. Label one of the jars with the sample site, treatment (e.g. soil type) and the initials of the investigator.
  2. Dig a 25 cm x 25 cm x 25 cm cube of soil, setting the soil on the tarp.
  3. By hand, break the soil up into clumps. Any earthworms should be immediately set aside in the sample jar. Also set aside any earthworm cocoons. Keep an eye out for small species.
  4. When you are finished, replace the (earthworm-free!) soil in the hole.
  5. Repeat the above steps for each of the other sample locations. Bring the jars back to the laboratory as soon as possible for identification with the dissecting microscope.
  6. To identify worms with the microscope, consult the attachments at the bottom of this page, provided by Worm Watch Canada.
Sorting soil by hand to locate earthworms.
Nick Bader,
Jan 12, 2012, 12:53 PM
Nick Bader,
Jan 12, 2012, 12:54 PM