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Providing evidence to improve practice

Individual study: Earthworms are more abundant under no-tillage, but less abundant with reduced fertilizer input, on spring barley plots in eastern Scotland

Published source details

Gerard B.M. & Hay R.K.M. (1979) The effect on earthworms of ploughing, tined cultivation, direct drilling and nitrogen in a barley monoculture system. Journal of Agricultural Science, 93, 147-155


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Reduce fertilizer, pesticide or herbicide use generally Farmland Conservation

A replicated trial on an experimental farm in eastern Scotland (Gerard & Hay 1979) found fewer earthworms (Lumbricidae) at lower nitrogen application rates. There were 78 earthworms/m2 and 0.42 tonnes earthworm/ha in plots with no nitrogen, compared to 106 earthworms/m2 and 0.53 tonnes/ha in plots with 100 kg N/ha. The highest nitrogen treatment (150 kg N/ha) had fewer earthworms but higher biomass because there were more large-bodied species like Lumbricus terrestris (93 earthworms/m2, 0.59 tonnes/ha). Earthworm biomass decreased with decreasing nitrogen application at a rate of 0.06 t/ha for every 50 kg N/ha. Only one of the eight species recorded, Allolobophora rosea, was more abundant in plots with lower fertilizer inputs (9 earthworms/m2 at 0 kg N/ha, compared to 3.7 earthworms/m2 at the highest rate of 150 kg/ha). The experiment was replicated eight times. Spring barley crops were managed from 1967 until 1973 with either 0, 50, 100 or 150 kg N/ha added annually.

 

Reduce tillage Farmland Conservation

A replicated trial on an experimental farm in eastern Scotland (Gerard & Hay 1979) found that the average number and biomass of earthworms (Lumbricidae) was significantly higher in untilled soil (137 earthworms/m2 and 0.9 tonnes earthworm/ha) than in cultivated treatments (67-93 earthworms/m2 and 0.3-0.4 tonnes/ha). The experiment was replicated eight times. Spring barley crops were managed from 1967 until 1973 with either deep ploughing (30-35 cm), normal ploughing (15-20 cm), tined cultivation (12-30 cm deep) or no ploughing (untilled, direct drilled). Between 1969 and 1973, the average number of adult and large juvenile earthworms on two replicates increased from 37 earthworms/m2 to 114 worms/m2 under direct drilling, but did not change significantly under the three cultivation treatments (21 to 80 earthworms/m2).