Question
thanks for such a speedy reply. I dont think its a mole because the piles are only about 1 to 2 inches. Do worms make holes with piles? Can I send you a picture? What do worm holes look like?          
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Followup To

Question -
i live 30 miles south of macon GA and have a centapeed lawn. in addition to a few ant hills we have severak mounds of dirt in short segments (about 1/8 inch) piled up like ant hills, but there are no bugs or worm holes to be found. if you touch them they crumble into sand. any ideas? they dont seem to cause a problem but there are 100's of them.

Answer -
If you have mounds of dirt like small volcanos or "puffs of dirt" then it is likely the eastern mole.

You can contact an exterminator, or try to buy traps.  

Answer
I might have misunderstood your last post (I thought you said that it was not worm holes).

Earth worms do makes mounds of dirt which would be small. These are the castings but they are tyically black or gray and clinging together. Some look like the shape of a worm while others look like round pellets fused together.

The best way is to avoid worms is too keep leaves and dead plant parts of lawn by raking. If you fertilize with organic fertilizer items such as bone meal and dried blood you may also find more worms because they tend to favor these foods. However, worms in the lawn is typically a good sign of a healthy soil.

I found these pictures for you:
http://www.rhs.org.uk/advice/profiles1001/images/worm_cast.jpg

http://www.wirralseafishing.co.uk/images/lugcast.jpg

http://chaplog.co.uk/mike/images/single%20worm%20cast.jpg


If what you are finding are small sand like structures less than an inch high, then I suspect ants. You can try to bait them with sugar or professional traps to determine it. You can also pick up ant motels (traps) at the supermarket.