EARTHWORM POPULATIONS RECOVER AFTER POTATO CROPPING

Potato cropping in southern Australia can involve up to 30 passes with a tractor, with up to 15 cultivations and multiple applications of fe rtilisers, fungicides, herbicides and insecticides. This was expected to significantly affect earthworm activity. Earthworms from four pastu re sites were compared with those from adjacent potato paddocks. In th e year following potatoes, earthworm numbers were about half in the pa ddocks which had been cropped. When the same sites were again sampled in the following year, populations had recovered and, on one held, wer e significantly higher in the second year after potatoes than in the a djacent pasture. This relatively rapid recovery, following substantial soil disturbance, may have been associated with the increased pH with lime added to the cropped paddocks. (C) 1997 Elsevier Science Ltd.