Earthworms stimulate pasture production in sheep and beef systems: their economic value

Abstract

Earthworms have long been recognised to promote plant growth but their contribution to pasture production in managed pastures may be undervalued. At three field sites pasture production was measured in an area where surface active communities were found compared to a more diverse area where the additional deep burrowing earthworm Aporrectodea longa had been introduced. Caution is needed when interpreting the results, as all data are from paired areas and not replicates. The influence of earthworms on pasture production was positively correlated with the difference in abundance of the topsoil species Aporrectodea caliginosa, with this species being more abundant in the presence of A. longa at two sites. Overall, the value of diverse earthworm communities to pasture production was estimated to be $365-$440/ha annually. In managed pasture systems there is need to recognise the value of maintaining and enhancing earthworm populations. Keywords: pasture production, earthworm functional diversity