Action: Make selective use of spring herbicides
A replicated, controlled, randomized study in the UK found that spring herbicides had some benefits for beneficial weeds and arthropods.
This intervention aims to reduce herbicide inputs in fields which do not contain undesirable weed species. It involves not applying an autumn herbicide and reducing spring herbicide applications to a single treatment of a selective herbicide. Reducing spring herbicide treatment to a single application may allow a diverse weed community to develop.
Supporting evidence from individual studies
A replicated, controlled, randomized study from 2003 to 2005 of arable fields at three sites in the UK (Jones & Smith 2007) found that spring herbicides had some benefits for beneficial weeds and arthropods. Species richness and cover of beneficial weeds tended to be higher with single spring or post-emergence herbicide applications than pre-emergence or combinations of applications; figures were lowest in plots with three annual applications. Cover of undesirable weeds was higher in single spring or pre-emergence applications than combined treatments. Single applications tended to reduce arthropod abundance less than sequences of herbicides, although post-emergence and pre-emergence applications were detrimental to some taxa. There were three or five replicate plots (3 or 4 x 24 m) of each treatment per site: untreated, pre-emergence, post-emergence or spring applications or combinations of each two/all herbicide applications. Vegetation was sampled in five quadrats (0.25 m²) in each plot (June 2003-2005). Arthropods were sampled using a D-Vac suction sampler (five sub-samples of 10s/plot) in a sub-set of treatments (June).