Test No. 256: Determination of effects on earthworms (Oligochaeta, Annelida) in Field Studies

This Test Guideline is designed to be used for assessing short- and long-term effects of chemicals on earthworms in soils under field conditions. Species diversity, abundance and biomass of earthworm communities collected from test plots in the field treated with a test chemical are compared with those collected from untreated control plots. Sampling is performed on at least four occasions during the year with one pre-sampling within 2 weeks prior to the application, and at least three post-samplings after application (ca. 1 month, 5-7 months and 12 months after application). Sampling is performed by a combination of two methods: hand-sorting and an application of an extraction fluid. The test duration is usually one year but may be prolonged depending on the properties of the test chemical and/or the effects observed after one year. Test endpoints include abundance and biomass of total earthworms, of single species, of life stages, of morphological groups, and of the relevant ecological groups.