(Editor's Note: This article was originally published on March 28, 2007)

At 70% protein, earthworms make a nice meaty snack for birds, reptiles and mammals, especially moles. Because we certainly don't want to go around wiping out birds, reptiles and mammals, we'll let them have their share. But there are some sinister characters lurking in the soil.

In certain conditions, red mites can attack earthworms. If you see red dots on earthworms in your yard, you should cut down on the moisture in that area - it may be too wet. Also, placing pieces of watermelon or potato on the soil surface will draw and trap the mites. Dispose of the pieces and repeat the process to cut down the mite population over time.

Flatworms, otherwise known as land planarians, are probably an earthworm's most hated rival. These long, slimy, longitudinal-striped worms with a flattened head -- a native of Indo-China that hitched a ride on greenhouse plants -- will actually melt earthworms with an enzyme before slurping them up. And they do it a lot. Blech.

The best control if you see a flatworm is to spray it with citrus oil or vinegar. Whatever you do, don't smash it, because each piece has the ability to regenerate into a new flatworm. Double blech.