CAHL3Grassy field corners or blocks

What it actually is

A corner or a block of an arable or horticultural field that stops being cropped and becomes grass for three years. GOV.UK's stated aim is an intact grass sward throughout the year, without tracks, compacted areas or poaching, allowed to develop tussocky grass. The page sets that in the context of year-round habitat for wildlife and support for integrated pest management next to the cropped area.

You establish it either by sowing or by allowing natural regeneration, within twelve months of the action's start date, and it stays in the same place for the whole three years.

Source: GOV.UK, CAHL3 action page, checked 04/08/2026.

Our own way of putting that, which adds no requirement beyond what the GOV.UK action page sets out: the word tussocky is doing something unusual here. On most grass actions an untidy sward is a failure. On this one it is the aim.

What it pays, and what that comes to

The rate is in the panel at the top of this page. Multiplied out:

Source: arithmetic on the payment rate shown at the top of this page, which comes from Tilth's copy of the GOV.UK action catalogue and carries its own last-checked date. The 2 hectares is an illustration.

Two hectares is not much of a block, but it is a realistic total once the awkward corners of a whole farm are added up, which is how this action tends to be used.

Is it worth it on your ground?

Step one: what it costs to put in. This is the only action on this site where the answer can honestly be nothing. GOV.UK allows establishment by natural regeneration as well as by sowing. Where the ground will green over on its own, there is no seed to buy.

Where you would rather sow it, an indicative grass seed cost:

Source: ProGreen, own listed price and stated sowing rate for a 4/6 metre grass and buffer strip mix, looked up 31/07/2026. That is a buffer strip mix rather than a mix sold specifically for this action, so treat the figure as an indication of what grass seed costs rather than a quote. Price your own. Cultivation and drilling are your own cost and are not included.

Step two: what the ground would otherwise return. Gross margins per hectare for England, non-organic, in the 2023/24 crop year. Variable costs have already been taken off these figures, so there is nothing further to deduct.

Source: Farm Business Survey, Crop Production in England 2023/24, Rural Business Research, England, non-organic, 2023/24 column, checked 02/08/2026. The winter wheat figures come from a sample of 572 farms.

The agreement runs three years, so the comparison has to run three years too, and that ground will not be in wheat for all three of them. Three rotations, worked from the crop figures above:

Source: arithmetic on the crop gross margins in step two, from the Farm Business Survey, Crop Production in England 2023/24, checked 02/08/2026. These three are illustrations. Work your own out from the same crop figures.

Step three: the gap.

Source: the payment rate at the top of this page, less the seed cost in step one where relevant, set against the rotation averages in step two. The remaining figures are subtraction.

Three things to set against those figures. What follows is Tilth's own reading rather than scheme guidance.

The survey reports one winter wheat figure, not first and second wheat separately. A rotation with two wheats in it carries a second wheat at the same gross margin as the first, which is unlikely to be how it turns out on your ground. We have not found a published split to cite, so we have not applied a discount of our own invention. Read the rotation averages as the generous end for the crop.

It is one year, and not a strong one. The same report's 2022/23 column put winter wheat's gross margin at £1,570 a hectare against the £988 above for 2023/24. A three-year decision resting on a single crop year is a shaky thing, and this particular year was the lower of the two.

A field corner is not the field. This is the heart of it, and it is the same argument as the buffer strip page. The gross margins above are field averages. A corner is the ground you double drill, overlap on, turn on and get stuck in, often shaded on two sides by a hedge and wetter than the rest. Nobody publishes a yield for it, we are not going to invent one, and the comparison to make is that corner's own return against the figures above rather than the field's.

Where that leaves it. On ground that performs like the field average, the crop is ahead by roughly £174 to £284 a hectare a year and this action does not pay. The case for it is that a field corner is almost never ground that performs like the field average, and that the corners on most farms are where the yield map goes pale. If your corners crop as well as your middles, do not do this. If they do not, this action turns the worst two hectares on the farm into a known figure that arrives every year regardless of the season.

One thing the gap does not carry. Taking a corner out also takes out the passes you make on it: the overlap, the awkward turn, the point where the drill gets lifted and put down again. That is real, and it is time as much as fuel. We have not put a figure on it because it depends entirely on your kit, your field shape and how you cost your own hours, and a made-up number here would be worth less than the honest gap.

What you actually have to do

Establish and maintain grassy field corners or blocks on the arable or horticultural land entered into the action, by sowing or by allowing natural regeneration, within twelve months of the action's start date.

During the first twelve months you may cut or graze to control weeds and encourage the grass to establish. After that, the aim is an intact grass sward throughout the year, without tracks, compacted areas or poaching, allowed to develop tussocky grass.

The action is static. You must do it at the same location each year of its duration.

Source: GOV.UK, CAHL3 action page, checked 04/08/2026.

What you cannot do on it

Once established: no grazing that would prevent the action's aim being achieved. No cutting, except to control injurious weeds, invasive non-native species, soft and hard rush, nettles or bracken. No regular vehicular access or storage. No fertilisers, manures or lime. No pesticides, except herbicides used for targeted weed control.

Source: GOV.UK, CAHL3 action page, checked 04/08/2026.

Where it can go, and the cap

Agricultural land below the moorland line that is an eligible land type, registered with a compatible land cover on your digital maps and declared with an appropriate land use code. That covers arable crops, leguminous and nitrogen-fixing crops, temporary grassland under TG01, fallow land under FA01, and horticultural permanent crops under TC01. You can enter the total or part of the available area in a land parcel.

Source: GOV.UK, CAHL3 action page, checked 04/08/2026.

CAHL3 is one of the ten limited area actions under SFI26. The rule is that the total eligible area you enter into them must not be more than 25 per cent of the total agricultural area of your farm. The other nine are CIPM2, CAHL1, CAHL2, CIGL1, CIGL2, WBD3, AHW7, AHW9 and AHW11.

Source: GOV.UK, SFI26 scheme rules and guidance, section 4.5, checked 02/08/2026.

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.

Natural regeneration is allowed, but it is not the same as doing nothing. The requirement you are judged against is an intact grass sward, not an absence of a crop. Natural regeneration is a legitimate way to get there and it is what makes this the cheapest establishment on the site. Whether it gets there on your ground, in twelve months, is a question about that particular corner, and the fallback if it does not is buying seed anyway a year later.

Static means three years in the same corner. No moving it in year two because that corner turned out to be where the muck heap needs to go. Pick a corner you are content to farm around for three seasons, and pick it with the whole rotation in front of you rather than this autumn's cropping plan.

The cutting rule reverses after the first year. In the first twelve months you may cut or graze to get the grass going. After that, cutting is only for the named problems: injurious weeds, invasive non-natives, soft and hard rush, nettles and bracken. So the management that establishes it is the management that would breach it later.

Tussocky is the aim, and it will look like neglect. A corner meeting this action properly looks untidy from the road and untidier from the field gate. That is the habitat working rather than a failure, and it is worth deciding you are comfortable with it before you enter the ground rather than reaching for the topper in year two.

No fertiliser, manure or lime. Lime is on the list here, which it is not on every grass action. On ground you would ordinarily be liming, that is worth noticing before rather than after.

A field corner is where things get put. No regular vehicular access or storage. The corner of a field is the natural place for a trailer, a bowser, a heap or a stack of pallets, and the same corner is the natural place for this action. The two want the same ground, so decide which one it is.

Awkward shapes are the whole point, and the area still has to be right. Payment follows the area you enter. A corner is rarely a shape you can pace out, and estimating generously is not a mistake in your favour. Measure it off the boundary rather than guessing at it.

The 25 per cent cap is shared, not per action. CAHL3 draws on the same allowance as CAHL1, CAHL2 and the rest of the ten. Whatever goes into one is not available to the others, so total them together before the form is filled in rather than deciding them separately.

Keeping the evidence

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

This is another action made largely of not doing things, and there is no invoice for a pass you did not make. Where it establishes by natural regeneration there may be no invoice at all.

What that suggests to us is that the useful records are the establishment date, whatever seed invoice exists if you sowed it, any cut made in the first twelve months and why, and any cut made later against which of the named weeds it was for. Dated photographs are doing real work on this one, because the difference between a corner in its first summer and the same corner in its third is the whole aim of the action, and it is visible in a way that a written note is not.

Tilth measures the corner off the field boundary you have already drawn and keeps the operations and photographs against it.

The part only your own ground can answer

Everything above turns on one question we cannot answer from a national survey: what that particular corner actually returns when you crop it. A corner on the field average leaves the crop comfortably ahead. A corner that has been quietly losing you money for years does not, and this action puts a known figure on it instead. Which corners those are is in your own yield records, field by field. Tilth keeps them there alongside the map. Request an invite.