Some guy was so serious about it he used a computer to calculate the odds and to tell him what to throw. He lost.
I found this:
Normally, earthworms are beneficial to lawns and soils in general. When they become too numerous,
they sometimes become pests because of the small mounds of castings that look unsightly in short grass types. An imported species, the oriental earthworm, is found in some eastern states. It is 6-8 inches long and about 1/5 inch in diameter. It is light green on the upper surface with a purplish-green line down the center of its back.
It throws up abundant castings.If I were a detective, I'd say case closed!
Cableguy-If you want, I will gladly come look(looks like you live in the Lantana area) and give a confirmation, but for the most part, they are good for that beautiful lawn you have!!