CAHL44m to 12m grass buffer strip on arable and horticultural land

What it actually is

A grass strip on an arable field edge that stays in grass for the whole agreement. It has to be an intact sward all year round, with no tracks, no compacted areas and no poaching. Area is measured as length in metres times width in metres, divided by 10,000.

Source: GOV.UK, CAHL4 action page, checked 31 July 2026.

What it pays, and what that comes to

Source: payment rate, GOV.UK CAHL4 action page, checked 31 July 2026. The 0.6 ha is arithmetic on the action page's own measurement rule: 1,000m × 6m ÷ 10,000.

Is it worth it on your ground?

Step one: what it costs to put in. Grass seed, once, at the start of a three-year agreement.

Source: ProGreen, own listed price and stated sowing rate for a 4/6 metre grass and buffer strip mix sold for CAHL4, looked up 31 July 2026. Price your own mix. Cultivation and drilling are your own cost and are not included.

Step two: the break-even.

Source: payment rate, GOV.UK CAHL4 action page, checked 31 July 2026. Seed as above. Feed wheat at £206.00/t, AHDB Arable Market Report, 27 July 2026 (East Anglia delivered, November 2026 delivery). Variable costs at £541/ha, Farm Business Survey, Crop Production in England 2019/20, England winter wheat (feed), a 2019/20 figure, and inputs have risen since, which pushes this break-even up.

Worked as (477 + 541) ÷ 206 = 4.94 tonnes a hectare.

Since this page was written we have found a newer figure. The Farm Business Survey's Crop Production in England 2023/24 puts England winter wheat (feed) variable costs at £789 a hectare, against the £541 used above. On £789 the break-even becomes 6.15 tonnes a hectare rather than 4.94, which moves the option's way. This page has not been reworked around it yet.

Step three: where does your headland sit? Against Defra's five-year average UK wheat yield of 7.8 t/ha (Agriculture in the United Kingdom 2025, Chapter 7), a break-even under 5 t/ha is a long way below average. So on a field that performs evenly, this does not pay.

But the field average is the wrong comparison for a headland, and that is the point of this action. The strip does not replace the average of the field. It replaces the outermost few metres. We are not going to tell you what your headland yields, because we do not know and we have not found a published figure we would be willing to put on a page about money. What we can say is that the comparison to make is the headland's own yield against 4.94 t/ha, not the field's. If you have yield maps, that number is already in them.

The honest reading. Where the outer few metres genuinely underperform the field, the break-even is easier to clear than the field-average figures suggest, and the ongoing requirements are one cut a year. Where the headland yields like the rest of the field, it does not pay.

One thing the break-even may understate. The action prohibits fertiliser and manure, and prohibits pesticides other than weed wiping or spot treatment for injurious weeds, invasive non-native species, nettles and bracken (GOV.UK, CAHL4 action page). Whether that changes the sum depends on how you cost the strip today: if the headland currently gets the same inputs as the rest of the field, then the £541 whole-field variable cost is about right for it and the break-even above stands. If you already treat the headland differently, put your own number in.

What you actually have to do

Establish the strip at least 4m and up to 12m wide, on average across each land parcel. Keep an intact grass sward all year, with no tracks, compacted areas or poaching.

In late summer, after the bird breeding season, cut part of the strip's width along the edge nearest the crop or fallow, along as much of its length as you can. The GOV.UK page gives the reason: it provides varied habitat.

Source: GOV.UK, CAHL4 action page, checked 31 July 2026.

What you cannot do on it

No regular vehicular access, turning or storage. No fertiliser or manure. No pesticides, except herbicides used to weed wipe or spot treat injurious weeds, invasive non-native species, nettles or bracken.

Source: GOV.UK, CAHL4 action page, checked 31 July 2026.

Things worth watching

This section is Tilth's own reading of where this action is easy to get wrong. It is not scheme guidance, it is not sourced from Defra or the RPA, and none of it adds a requirement beyond what the GOV.UK action page sets out.

Think about where you turn before you pick the field. The action prohibits regular vehicular access, turning and storage on the strip. A grass headland is also a natural place for a sprayer to turn, so the two want the same ground. If the strip would be where you turn, pick a different edge.

The width is an average across the land parcel. That helps where a boundary wanders. It also means the average is what is measured, so a stretch that narrows is only offset if there is a wider stretch elsewhere in the same parcel. Measure the whole parcel, not the narrowest point.

Poaching and tracking are named, not implied. The wording is an intact sward throughout the year, without tracks, compacted areas or poaching. It is worth knowing that those are set out specifically rather than left to judgement.

The late summer cut is a requirement, not an option. One pass, after the bird breeding season, on the crop side of the strip.

Keeping the evidence

Also Tilth's own reading. GOV.UK sets the requirements; this is a practical suggestion about record keeping.

The measurement is the one to get right, because the payment is calculated from length times width. Alongside it, the records that would let you show you have met the action are the seed invoice, the establishment date, and the date of the late summer cut.

Tilth measures the strip off the field boundary you have already drawn and keeps the cutting date against it.

The bit where we say what Tilth does

Tilth measures your strips off your own boundaries and keeps the establishment and cutting records against the field. Request an invite.