Burial of soil-surface artifacts in the presence of lumbricid earthworms

Rings of wire placed on the soil surface of two pastures containing populations of Lumbricidae were recovered after 52 months. They had been buried at the rate of 9–10 mm per year. At a forest site where only Megascolecidae were present there was no burial. At the pasture sites, populations of Lumbricidae in tubes of soil sterilized with methyl bromide 52 months earlier were indistinguishable from those in untreated soils.