Managing Margins with Nature in Mind

Thinking "outside the field" and managing the margins with nature in mind can contribute to the improvement of biodiversity on Irish farms. Aoife Leader, Teagasc Walsh Scholar, highlights some key actions that farmers can take to retain, maintain and enhance field margins for farmland biodiversity

To play on the metaphor of thinking outside the box, thinking outside the field and managing the margins with nature in mind can contribute to the improvement of biodiversity on Irish farms. Field margins are important habitats and networks for nature that provide corridors for the movement of wildlife and a place for native flora to flourish. In this article, Aoife Leader, Teagasc Walsh Scholar, highlights some of the key actions that farmers can take to ensure that field margins are retained, maintained, and enhanced for farmland biodiversity.

The role of field margins

Field margins are easy-to-manage strips of naturally growing vegetation that are found along the edge of fields beside linear features like hedgerows. Field margins are extremely valuable biodiversity habitats that are structurally different from what you might find in the centre of a ryegrass field. They are comprised of a variety of plants including naturally growing wildflowers and grasses that produce flowers and seeds which benefit seed-eating birds like the House Sparrow, the Linnet and the Yellowhammer and pollinators like Bumble bees and Solitary bees who avail of pollen and nectar from the margin’s flowering plants. Field margins facilitate the movement of wildlife throughout the farming landscape acting as a highway for nature and providing cover for small mammals like shrews and voles, in turn providing owls with an ideal hunting ground.

Field margin Do's and Don'ts

Field margins require some management in order to optimise them as habitats for biodiversity. In grazing situations, field margins should be fenced off to exclude livestock. The area that is fenced can range in width with wider margins providing more room for biodiversity. This action will further enhance the structural diversity of the margin by allowing vegetation to flower and go-to-seed. Margins should be cut in autumn after plants have flowered, at least once every three years, and this will prevent the vegetation within the margin becoming too rank or turning into scrub.

In addition, a minimum space of 1.5m between the main field crop and the base of the surrounding boundary should be maintained when spraying, cultivating, and applying fertiliser. Increasing the width of field margins reduces the need for sprays as the space created will allow for a hedge cutter to mechanically control any encroachment. Blanket spraying under the wire should be avoided as this will lead to the removal of plant diversity. Only noxious weeds (ragwort, thistle, docks, male wild hop, common barberry, and wild oats) should be controlled chemically, in line with the Noxious Weed Act and to do so targeted spot spraying should be practiced. As is the case with spraying, cultivation also leads to the removal of field margin habitats. Maintaining a minimum distance of 1.5m out from the base of boundaries when cultivating will ensure that an area of margin remains undisturbed allowing the existing diversity to continue to flourish. Good fertiliser management practices are also key to ensuring field margins are diverse habitats as soils that are high in fertility encourage the growth of nutrient loving plants like nettles, docks and thistles which will outcompete more desirable plants and so chemical fertiliser, slurry, manure and lime should not be applied within in field margins. There is no need to sow any seed mixes within field margins as with the above management practices native plants will naturally flourish.

Think M.A.R.G.I.N.S.

So, when it comes to doing more for biodiversity on your farm just think of the actions you can take around the M.A.R.G.I.N.S.

Mange for Nature

Avoid Spraying

Retain when Cultivating

Good Fertiliser Management

Increase Width

Native Plants Growing Naturally

Seasonal Cutting

Aoife Leader, Teagasc Walsh Scholar has more on Margins in this short clip below

For more information on the Teagasc Walsh Scholarship Programme here

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