OPAL Soil and Earthworm Survey

Data entry for the OPAL Soil and Earthworm Survey is now closed.  However, survey resources and identification guides can still be downloaded for free below. 

Thank you to all those who took part in the survey!

Survey data submissions can be viewed on the OPAL Data Explorer. In addition, OPAL Soil and Earthworm Survey data will soon be available for download from the OPAL website.


Discover the world of worms in your local area.

Group of boys holding a worm

The best time to do this survey is from March to September.

Earthworms are extremely important and play a vital role in recycling plant nutrients and aerating the soil.

How to take part

Taking part is simple and fun.

  • Step 1 – Download and print the documents in English below, or in Welsh, ideally in colour.
  • Step 2 – You'll also need a few everyday items including pH strips, mustard, vinegar and a ruler.
  • Step 3 – Find a suitable area and start looking for worms.

Downloads – what you need to take part

Survey pack

Also available:

Looking for the Welsh language survey pack?

By downloading this survey you agree to the terms and conditions for the OPAL Soil and Earthworm Survey

Group leaders and schools

Download our group leader support guide, example risk assessment, and our new printable black and white recording sheets.

Earthworm guide

An earthwormDo you know your lob worm from your brandling worm? Get in the know with our online guide.

Children's activity sheets

Boy holding a wormMake your own wormery with the soil and earthworm activity sheets available in our Kids Zone.

Watch it

Watch it

Watch it