Earthworms have a reputation as soil builders and renovators, particularly among 'organic' farmers and gardeners. They improve soil fertility through increased aeration, aggregation, water infiltration and release of nutrients from organic matter. However, the benefits of earthworms in the wheatbelt have been doubted for many years because of their poor survival in cultivated soils.
Since cropping began in the Western Auslmlian whealbelt over 1OO years ago, the physical condition of many soils has deteriorated. The primary causes of soil degradation were the European cultivation practices used by farmers and the trampling effect of introduced animals. in particular, sheep.
McCredie, Tom and Parker, Lex
"The role of earthworms in Western Australian agriculture,"
Journal of the Department of Agriculture, Western Australia, Series 4: Vol. 33
, Article 8.
Available at: http://researchlibrary.agric.wa.gov.au/journal_agriculture4/vol33/iss4/8