Arable and grass fields

While the volume of biocidesA chemical substance or microorganism intended to destroy, deter, or control harmful organisms such as bacteria, fungi, viruses, insects, or other pests. They are commonly used in disinfectants, wood preservatives, and pest control products. (such as herbicides, insecticides and fungicides) applied to farmland has decreased and targeting has improved, the compounds they contain have become considerably more effective, both in intensity and spectrum of activity. 

On grassland, the main pesticides used are wormers (nematicides) applied direct to livestock, either through ingestion or as pour-ons. Some of these (such as ivermectins) are known to be highly persistent in the environment, killing invertebrates that live in dung for example. Treatments used to control blowflies and face flies may also be having widespread adverse effects, although research on this is currently lacking and a precautionary approach should be taken.

Rising costs, the continued loss of products that protect plants and animals and rising levels of resistance mean that the options for pesticides are shrinking. Integrated Pest Management (IPM) is a coordinated farm strategy that includes the use of insects as a natural pest control. See Find out more below for more information.

The heavy application of fertilizers, whether artificial or manures, causes severe environmental harm. The effects include raising the nutrient status of field margins and hedge bases so they become dominated by nettles and goosegrass, contaminating waterways and damaging soil health and function. They also cause air pollution by increasing atmospheric nitrogen, known to be causing significant damage to many wildlife habitats, and through ammonia release that’s damaging communities of lichens (see the Air quality page for more information).

Integrated Farm Management (IFM), organic farming and other regenerative practices such as mob grazing and the use of herbal leys, aim to improve soil health and benefit biodiversity. The popularity of these nature-friendly approaches is increasing among farmers.

Over much of the UK, minimum tillage (min-till) or even no tillage (no-till) have been introduced, reducing soil disturbance. Depending on the soil type and depth of cultivation, min- or no-till decreases fossil fuel use and labour costs, increases carbon storage and nutrient and water retention, and generally improves soil health and biodiversity.  However, it can also increase the abundance of perennial and annual grass weeds at the expense of other arable plants. Where soils are already compacted minimum tillage will not on its own restore soil health and without other soil restoration measures can lead to further deterioration and therefore reduced carbon storage and increased soil run-off. See Rocks and soils for more information.

There’s also growing understanding of how flower-rich grasslands produce high-quality meat and dairy, which can improve human health and increase farm income.

Maize is now widely grown on livestock farms for silage. However, the necessary soil cultivation and high use of fertilizers and pesticides often causes soil loss, severe water pollution and environmental contamination. It’s also often accompanied by the loss of field margins, through ploughing and herbicide use right up to the field edges.

There’s increasing interest in planting trees in both arable and grass fields, to increase overall productivity and the health of the environment, including wildlife. Tree planting in fields is currently being promoted through agri-environment schemes. See Trees outside woodlands for more information and useful links.

The importance of arable fields for rare plants and farmland birds is not well recognised. In some cases, wildlife has declined due to the intensification of arable farming (see the About section above). However, arable fields that support rare plants and birds have also been lost as a result of inappropriate agri-environment options or converted to grassland due to a misconception that this is better for wildlife.

In comparison with other habitats, the wildlife value of arable land is poorly understood. This is partly because it covers so much land, making it difficult to survey. However, it’s also because crop types, agricultural inputs and the timing of operations vary between years, creating very different conditions. Rare arable plants can be dormant as seed in the soil for many years, only appearing when conditions such as weather and crop management are right. 

There are currently no accepted standard methods for botanical survey or condition assessment for arable habitats, and no national register of biodiverse arable sites. These are significant obstacles to the conservation of arable biodiversity.

Arable field margins (as a UK priority habitat) are poorly defined. See Find out more below for more information and suggested national actions.

Arable and grass fields are fundamental elements of the agricultural landscape and of great for food production and to the economy. Any changes to their management must be evaluated within this context. Implementing actions for sustainable farming and nature (such as Integrated Pest Management) can lead to cost savings, especially in the long term. However, many actions for nature and public goodsA commodity, product or service that’s available to all and that everyone can use repeatedly without reducing its availability to others, typically provided by a government and funded through taxes. such as natural flood management, need to be supported by public payments, usually through agri-environment schemes but also sometimes through private (green) finance. Others are carried out by farmers for the sheer enjoyment of helping wildlife thrive.

Grassland provides important opportunities to preserve archaeological remains. There are also archaeological and historic landscape features that are specific to grassland, such as bedwork water meadows and hillslope catch meadows.

The limestone plateau grasslands around Torbay in south Devon preserve evidence of early (prehistoric and Roman) field systems and settlements. Although arable is not good for archaeology, non-ploughed margins could be designed to better protect sensitive archaeology.