A reader recently posted a photograph to our Facebook page with the following message, “When it rains I get a lot of the standard earthworms but a ton of these grayish worms as well. Not sure if they are just dying or if they are a different species. They look very similar but are typically smaller.”

The excellent photo shoes a dirt patch covered in worms. Some of these worms are typical earthworms. They are slightly pink, long, and segmented. The other worms are smaller, and have a more gray/green coloring to them. Here is the photograph our reader sent:

We are confident that these gray worms are also earthworms, but they might be a different type. There are four different types of earthworms: night crawlers, garden (or field) worms, manure worms, and red worms (or red wigglers). Although these earthworms might all be found in a garden, they prefer different types of soil and might vary in appearance. The larger worms in the picture might be night crawlers or garden worms, and the smaller are also garden worms.

It is very possible that these worms all belong to the same category of earthworms, and that their color and size variations stem from dietary differences. We do not think that these worms are dying.

In summary, a reader sent us a photograph of some earthworms he found after some heavy rain. After considering the differences in size and color, we believe that these are all earthworms.