Providing evidence to improve practice

Action: Restrict certain pesticides Farmland Conservation

Key messages

  • A small scale study in the UK found that using the fungicides Propiconazole and Triadimefon reduced chick food insect abundance less than using Pyrazophos. A replicated, controlled trial in Switzerland found that applying metaldehyde slug pellets in a 50 cm band along the field edge adjacent to wildflower strips provided equivalent crop protection to broadcasting the pellets across the whole field.

 

Supporting evidence from individual studies

1 

A small scale study in 1984-1985 of cereal fields treated with foliar fungicides (fungicides for fungal leaf diseases) in the UK (Sotherton & Rands 1987) found that chick food insect abundance was reduced to a greater extent following applications of Pyrazophos compared to other fungicides. Compared to untreated crops, chick food insects were reduced by 31-70% in crops treated with Pyrazophos, 10% with Propiconazole and 3% with Triadimefon applications. The effect of Pyrazophos was greater when applied to crops at an earlier growth stage (GS) (GS37: 70% reduction in chick food insects, GS50: 45%, GS60: 31%). Following Pyrazophos applications, total predatory arthropods were reduced by 25-48%, aphid-specific predators 35-84% (17% with Triadimefon) and parasitoids 34-55%. Fungicides were sprayed at GS50 in winter wheat in 1984. Pyrazophos was also sprayed at GS60 in spring barley (1984) and GS37 in winter barley (1985). Chick food insects were sampled by sweep nets or suction sampling.

2 

A replicated, controlled trial of slug (class: Gastropoda) control techniques in autumn 1996 in two oilseed rape Brassica napus arable fields near Bern, Switzerland (Friedli & Frank 1998), found that metaldehyde pellets applied in a 50 cm band alongside wildflower strips provided equivalent crop protection to broadcasting pellets across the entire field. Untreated control plots suffered severe crop damage. Slug sampling showed that Arion lusitanicus caused the majority of damage in plots 1 m from wildflower strips. The treatments trialled were broadcasting pellets across the entire plot at a density of 10 kg/ha, 50 cm of pellets alongside wildflower strips at 20 kg/ha and at 40 kg/ha, and control plots with no metaldehyde applied. Slugs were sampled on eight nights using bait stations.

Referenced papers

Please cite as:

Dicks, L.V., Ashpole, J.E., Dänhardt, J., James, K., Jönsson, A., Randall, N., Showler, D.A., Smith, R.K., Turpie, S., Williams D.R. & Sutherland, W.J. (2018) Farmland Conservation Pages 245-284 in: W.J. Sutherland, L.V. Dicks, N. Ockendon, S.O. Petrovan & R.K. Smith (eds) What Works in Conservation 2018. Open Book Publishers, Cambridge, UK.