Effect of five species of earthworm on some soil properties.
The casting and burrowing activities of Allolobophora caliginosa, A. longa, A. trapezoides, Lumbricus rubellus and Octolasion cyaneum were studied in the laboratory and the ability of each species to mix surface-applied lime into the soil was studied in the laboratory and the field. Species differed in their surface activity, L. rubellus, opening more burrows towards the end of the dark period, A. longa towards the middle, whereas A. caliginosa and A. trapezoides showed no clear pattern and O. cyaneum did not come to the surface. Burrows opened to the surface tended to remain open for at least 12 days and tended to reappear in the same place after disturbance of the surface soil. In the laboratory A. caliginosa and L. rubellus tended to mix lime laterally and A. longa to mix it vertically. In the field A. longa increased the vertical mixing of lime and also was shown to bring buried lime to the soil surface.