Long-term trends are not yet known for A. longa in southern Australia, but significant increases in pasture production have been maintained for many years following the introduction of appropriate earthworms in New Zealand. In a glass-house trial, the addition of A. longa to A. caliginosa populations also increased pasture production. Similar additive effects between these two species have been reported for field trials in New Zealand and Tasmania. Soil acidity is a major agricultural and environmental problem in the high rainfall regions of Australia. The use of ammonium-based nitrogen fertilisers and nitrogen fixing legumes has contributed significantly to soil acidification.
Soil acidity is a major contributor to soil degradation and reduced plant production.
Lime is applied to the surface of the soil to offset acidity but it is generally slow to move into the root zone where it is needed. It is often too costly or inappropriate to incorporate lime mechanically using tillage. The results found that A. longa buries lime deeper than A. caliginosa and A. trapezoides. Lime burial increases with earthworm density. Results from several field trials throughout South Australia and western Victoria suggest that the threshold in population density required for a significant influence on lime burial in one season was less for A. longa than other species tested.