Individual study: Adoption of conservation headlands to Finnish farming
Helenius J. (1994) Adoption of conservation headlands to Finnish farming. British Crop Protection Council Monographs, 58, 191-196
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
Leave headlands in fields unsprayed (conservation headlands)
A replicated, controlled study in 1992-1994 of headlands of spring cereal fields on four farms in central and southern Finland (Helenius 1994) found that arable weed density and the abundance of some insect groups were higher in unsprayed headlands compared to sprayed headlands, weed diversity did not differ. Weed density was significantly higher in unsprayed conservation headlands (275-420/m) than sprayed headlands (160-371/m). However, numbers of species were similar in both treatments (31-38 vs 31-36). The following insect groups were more abundant in conservation headlands than sprayed headlands: leafhoppers/planthoppers/aphids (Homoptera) 112-1401 individuals vs 85-706, flies (Diptera) 77-80 vs 69-74, bees/wasps/ants (Hymenoptera) 34-58 vs 29-46, true bugs (Heteroptera) 9-109 vs 7-43 and beetles (Coleoptera) 7-14 vs 5-7. In contrast, thrips (Thysanoptera) were more abundant in sprayed headlands (746-1846 vs 591-960). Twelve conservation (no pesticides) and control headlands (herbicide and insecticides) 4-6 m wide and 100-200 m long were established. Weed abundance was sampled in three pairs (0.5 and 3 m from the crop edge) of 0.25 m² quadrats per headland in late July. Insects were sampled using a D-Vac (five x 10 s per sample) at the same locations as plant quadrats in early July. A sweep net sample (2 x 15 sweeps) was also taken from each headland.