Observations on earthworm populations in orchard soils.

Abstract

At three sites, fields employed for some years in field-management studies were examined; each site had a fairly light soil with a silt content of 23-25 %. In the three sites maximum worm densities of about 300, 500 and 430/m² were found in grass plots; the densities under green-manure crops at two of the sites were 25 and 150/m^a and in clean-cultivated plots at the third site the density was 30/m⁸. The small species, Allolobophora caliginosa, A. rosea and A. chlorotica, responded more clearly than the large species, Lumbricus terrestris and A. longa, to the various soil treatments. Generally plots with short grass were more densely populated than those with long grass. The percentage of water-stable aggregation and the earthworm population were correlated. (Abstract retrieved from CAB Abstracts by CABI’s permission)