This year for the first time, farmers on derogation farms, who are availing of the Nitrates Derogation, have committed to undertake a biodiversity option, according to Teagasc.

The value that hedges on Irish farms contribute to biodiversity, carbon sequestration and landscape is increasingly being recognised under legislation and cross-compliance.

Hedge cutting can be carried out between September 1 until the end of February, with the cutting of hedges prohibited during the bird-nesting season.

Farmers in derogation must undertake at least one of two options where hedge cutting is being carried out.

Option one

The first option farmers have is to keep at least one thorn tree in every 300m of hedge; this can be either a whitethorn or blackthorn.

While one tree every 300m may seem low, it will allow for other new thorn trees to develop in the future, giving a diversity of height, rather than all at one height.

This will lead to hedges or lines of trees which are never topped, as they contain numerous thorn trees with a full canopy providing flowers and fruit. Annual side trimming, little and often is allowed in option one. It can be an existing mature thorn tree, but these are rare in topped hedges.

Option two

The second option for farmers is to maintain hedgerows on a minimum three-year cycle. Teagasc has recommended to cut one-third of the hedges each year. Where all hedges were cut in 2019, cut one-third in each of 2020, 2021 and 2022.

Cutting annually stops flowering and fruiting. The trees provide flowers for bees and their haws provide food for birds such as the blackbird, thrush and robin, who nest in the body of the hedge. Birds will not sit on top of flat-topped hedges.