How to turn pasture data into clearer grazing decisions

Use average pasture cover, growth rate, paddock distribution and farm-specific targets to decide what needs to change next.

Pasture data is useful when it informs a decision

You’ve finished the pasture walk, checked the latest readings or opened the farm dashboard. The numbers are there. But the useful question is still the same: does tomorrow’s grazing plan need to change?

A pasture reading on its own won’t answer that. It becomes useful when you set it alongside herd demand, recent growth, paddock order, residuals and what you can see happening on the farm.

That doesn’t mean replacing experience with a screen. It means giving your experience a consistent farm-wide picture to work from.

💡Tip: If you’re still building a measurement routine, start with our guide to measuring pasture. If the basics of rotation are the part you’re working through, Rotational Grazing 101 covers paddock planning and the practical fundamentals.

The working routine is straightforward:

• Establish your current feed position
• Check what has changed
• Decide whether the plan still fits
• Make one clear adjustment if it doesn’t
• Record the decision and check the result

Start with your current feed position

Your current feed position is more than one average number. It brings together:

• Available pasture in each paddock
• Average pasture cover across the grazing area
• The order and spread of paddock covers
• Recent and expected pasture growth
• Herd demand and planned allocations
• Pre-grazing covers and post-grazing residuals
• Recent grazing, conservation and supplementary feeding
• The next planned grazing dates

Together, these tell you whether feed supply and demand are reasonably aligned—and where that balance may be starting to shift.

A feed wedge is useful here because it ranks paddocks by pasture cover for a selected point in time. Its shape helps show whether a surplus or deficit may be developing, while paddock order gives you a practical starting point for deciding what to graze next. For a fuller explanation, see how to read and use a feed wedge.

In Pasture.io, the Feed Wedge follows the date selected on the Farm Dashboard, so you can compare the farm’s feed position at different points in time. Future-dated grazing records add a predictive view. You can also filter the paddocks shown, change how the bars represent paddock area or total feed, and download the chart to discuss with your team. The Feed Wedge Help Centre guide provides detailed operating steps.

How to calculate Average Pasture Cover (APC)

Average pasture cover, usually written as APC, is the average amount of pasture dry matter across the grazing area. It is expressed in kilograms of dry matter per hectare, or kg DM/ha.

Where paddocks differ in size, calculate APC as an area-weighted average:

Average pasture cover = total pasture dry matter across all paddocks ÷ total grazing area

To find total pasture dry matter, multiply each paddock’s cover in kg DM/ha by its area in hectares, then add the paddock totals together. Divide that figure by the total hectares measured.

Here’s an illustrative example:

Paddock A: 2 ha × 2,600 kg DM/ha = 5,200 kg DM
Paddock B: 3 ha × 2,200 kg DM/ha = 6,600 kg DM
Paddock C: 1 ha × 1,700 kg DM/ha = 1,700 kg DM

The three paddocks hold an estimated 13,500 kg DM across 6 ha.

APC = 13,500 kg DM ÷ 6 ha = 2,250 kg DM/ha

If you searched for a pasture cover calculator, that is the basic calculation it is doing. On a real farm, the value depends on consistent paddock measurements, correct areas and the measurement method used.

APC is useful because it gives you a whole-farm reference point. It can show whether the overall feed position is rising or falling and help you compare actual cover with your farm’s seasonal plan.

But don’t stop at the average. Two farms—or two weeks on the same farm—can have the same APC and a very different paddock distribution. One might have an orderly run of paddocks near the desired pre-grazing cover. Another might have a few heavy paddocks masking a shortage through the rest of the round.

How to calculate pasture growth rate

Pasture growth rate is normally expressed as kg DM/ha/day. At paddock level, a practical calculation is:

Pasture growth rate = pasture grown since the last grazing ÷ number of days in the regrowth period

For example, if a paddock rises from a 1,500 kg DM/ha post-grazing residual to 2,700 kg DM/ha before the next grazing, it has grown an estimated 1,200 kg DM/ha. If that takes 24 days:

1,200 kg DM/ha ÷ 24 days = 50 kg DM/ha/day

This residual-to-next-grazing method depends on good records. At whole-farm level, software may calculate growth from repeated readings and farm activity, so understand the method and inputs before comparing one figure with another.

A growth rate is most useful when you compare it with feed demand. If pasture is growing faster than the herd is expected to consume it, a surplus may be building. If growth is below demand, average cover is likely to come under pressure unless something else changes.

That comparison isn’t a command to speed up or slow down immediately. First check the scale of the difference, how long it is likely to last, which paddocks are affected and whether the measurements agree with what you see on farm.

Use targets and residuals as guides, not universal instructions

We reviewed current guidance from DairyNZ, Dairy Australia, Teagasc and AHDB to find the practical advice that is consistent across pasture-based systems.

The common message is straightforward: graze perennial ryegrass while it is still leafy, avoid grazing so early that regrowth is weakened, and leave a suitable residual so the pasture can recover. Use published figures as starting points, then adjust them for your pasture type, herd, season and measurement method.

The exact numbers differ partly because pasture is not measured the same way everywhere. Some organisations report total pasture mass from ground level, others report pasture available above a set residual, and some use sward height. Two figures can therefore look very different while describing a similar grazing position.

Some useful reference points are:

• New Zealand: DairyNZ guidance places vegetative perennial ryegrass at about 2.5–3 live leaves, generally around 2,600–3,200 kg DM/ha. Its 2026 paddock guide uses a spring working range of around 2,800–3,200 kg DM/ha, with a spring to early-summer residual of 1,500–1,600 kg DM/ha, or 7–8 rising plate meter clicks.
• Australia: Dairy Australia advises grazing spring ryegrass at about the 2–2.5 leaf stage and retaining a 4–6 cm residual.
• Ireland: Teagasc uses a mid-season pre-grazing target around 1,400 kg DM/ha at 2.5–3 leaves. Its figures describe pasture available above a 4 cm residual, so they should not be compared directly with New Zealand total-cover figures.
• United Kingdom: AHDB uses total-cover targets around 2,500–3,000 kg DM/ha with a 1,500 kg DM/ha residual for many rotationally grazed cattle over eight months, while recognising that animal class and expected performance change the target.
• In North America, extension guidance often expresses the same rest-and-residual principle using pasture height rather than kg DM/ha. For South American and South African systems, use locally validated guidance for the dominant pasture species and measurement method rather than importing a New Zealand number.

The practical takeaway is to choose a regional range that matches your measurement method, then treat it as a starting point. Adjust the working target for stocking rate, desired intake, rotation length, season, conditions and what your own records show.

One useful way to turn those principles into a farm-specific pre-grazing target is:

Pre-grazing cover = (stocking rate × desired pasture intake × rotation length) + target residual

Using the inputs from DairyNZ’s 2026 paddock guide, 3 cows/ha × 18 kg DM/cow/day × a 21-day rotation gives a pasture demand of 1,134 kg DM/ha. Add a target residual of 1,500 kg DM/ha and the illustrative pre-grazing cover is 2,634 kg DM/ha:

(3 cows/ha × 18 kg DM/cow/day × 21 days) + 1,500 kg DM/ha = 2,634 kg DM/ha

This example uses a New Zealand total-cover basis. It is not a target to copy without checking the farm’s own inputs and measurement method.

If intake, stocking rate, rotation length or residual changes, the pre-grazing target changes too. Check whether cows are receiving the intended allocation, whether the desired residual is being achieved and whether pasture quality and regrowth remain on track.

Look beyond the whole-farm average

Once you have the average, look at the spread behind it.

Ask:

• Are several paddocks well above the working pre-grazing line?
• Are the next paddocks in the rotation ready, or is there a gap?
• Are low covers concentrated in one soil type, block or recent grazing period?
• Are residuals consistently higher or lower than planned?
• Has pasture quality changed as covers have built?
• Does the paddock order still make sense after rain, irrigation, fertiliser, conservation or a missed grazing?

Pasture quality matters because a kilogram of dry matter isn’t equally useful at every stage of growth. Cover, leaf stage, clover content, stem and contamination can all affect how the paddock will graze. The numbers provide a framework, but observation still tells you whether the pasture in front of the cows matches the assumptions behind the plan.

Identify what has changed

A good review is less about admiring the dashboard and more about spotting the change that matters.

The trigger might be:

• Growth moving above or below the working assumption
• Demand changing with cow numbers, intake or stage of lactation
• A group of paddocks moving ahead of the desired pre-grazing position
• Projected cover falling below the farm’s comfort range
• Residuals showing that allocation or intake assumptions are off
• Wet conditions making the planned paddock unsuitable
• A conservation decision changing the available grazing area
• The planned sequence no longer matching paddock readiness

Then ask whether the change is large enough (and likely to last long enough) to justify action. One odd reading may need checking, while a consistent trend across several paddocks deserves more attention.

On farms using manual field measurements, such as a plate meter or tow-behind pasture meter, checking may mean remeasuring an uncertain paddock or bringing the next farm walk forward. Pasture.io satellite plans update automatically when a usable image is available, while Pio’s Cloudy Days Model helps maintain cover and growth estimates during cloudy periods. Checking the data does not fix a feed gap; it helps confirm whether the gap is real, whether it is widening or easing, and whether a change you make is having the intended effect.

When you need a quick starting point, Pio Says Graze ranks paddocks using pasture cover, time since the last grazing or harvest, and available feed, assessed against your monthly targets. It is designed as a shortlist rather than an instruction: check the highest-ranked paddocks against weather, access, logistics and what you can see on farm. You can view the ranking in the paddock list, as a map overlay or in Reports. The Pio Says Graze Help Centre guide explains how the ranking works.

Turn the change into an action

A useful decision sequence is:

• Confirm the size and likely duration of the gap
• Check the paddock sequence and rotation
• Consider the practical options
• Choose the smallest sensible change
• Set a point to review it again

Surplus example

Imagine recent measurements show pasture growth consistently running ahead of herd demand. Several paddocks are moving above the farm’s working pre-grazing position, and the gap is widening.

Rather than waiting for those paddocks to become rank, you might check whether the faster growth is likely to continue, adjust the round, remove a suitable area for silage or consider topping where conservation isn’t appropriate. Our guide to topping pasture covers the practical considerations around that option.

The decision isn’t “growth is above demand, so make silage”. It is “a developing surplus is visible; which response best protects pasture quality and the next round on this farm?”

For Taranaki dairy farmer Logan Haynes, that earlier view is valuable. As he puts it:

He says that visibility helps when making silage and supplement decisions in both dry and wet conditions. His experience is specific to his farm, rather than a result every farm should expect.

Logan also uses historical paddock records to compare performance over time and identify where pasture improvement may be needed. That is a different job from the feed wedge, which compares paddocks at a selected point in time and helps him see when surplus paddocks can leave the grazing round for silage.

That result is specific to Logan’s farm. It shows how he has used a clearer paddock-by-paddock view, rather than an outcome every farm will necessarily achieve.

Once you have identified a genuine surplus, Pasture.io can also help you keep the decision flexible. You can create a harvest record for a future date, see the planned harvest paddocks marked with a yellow border, and edit the record to return a paddock to the grazing round if the feed position tightens before harvest. See the forward-planning harvest guide for the practical steps.

Deficit example

Now imagine recent measurements show pasture growth consistently falling behind herd demand. The projected feed position is declining and the next paddocks are not reaching the farm’s working pre-grazing position.

You might check the readings and weather outlook, review the rotation, test whether supplement is warranted, revisit allocation assumptions or consider whether demand can be reduced. The right response depends on how severe and persistent the gap is, what feed is available and what the cows are leaving behind.

Again, the data narrows the decision. It doesn’t make the decision without you.

Keep the plan current

A grazing plan is a working view, not something you set once and follow regardless of what changes.

Review it when the assumptions move materially: after a growth shift, a weather event, a change in herd demand, unexpected residuals, a conservation decision or a paddock dropping out of sequence. A steady review rhythm helps, but the point is to respond to meaningful change—not to update numbers for the sake of it.

Pasture.io brings pasture readings, grazing plans and farm records into one view. Its Feed Wedge helps show the current paddock distribution, while the Grazing Planner can be used to build and adjust the planned sequence. For more on the chart itself, the Predictive Feed Wedge guide explains how to read and use the view.

To look beyond the current feed position, the Scenario Feed Wedge lets you compare estimated feed positions 7, 14, 21 or 28 days ahead. You can test different pasture-growth or pasture-per-animal assumptions and exclude paddocks that will not be available. It does not create grazing events or change farm history, and the results are estimates rather than promises. Use it to compare options before changing the live plan. The Scenario Feed Wedge Help Centre guide provides the steps and limitations.

Record the decision and check the effect

Before you move on, note three things:

• What changed
• What action you took
• What the next reading or paddock observation showed

That closes the loop. Over time, it helps you see whether the original assumption was useful, whether the response worked as expected and whether the same pattern is showing up again.

It also gives the farm team a shared reason for the change. Instead of “we’ve moved the cows because the plan changed”, the explanation becomes “growth has slowed, the next paddocks are short of our working pre-grazing range, and we’re adjusting the round until we measure again”.

The useful outcome is a clearer next action

Pasture measurement is the starting point. The value comes from knowing what the readings mean for the next paddock, the next round and the feed decisions that sit around them.

Start with the current feed position. Check what has changed. Compare it with farm-specific targets and what you can see. Make one clear adjustment where it is needed, then check what happened.

That is how pasture data becomes part of practical farming judgement—rather than another set of numbers to keep up with.

See how Pasture.io brings pasture information, feed planning and grazing decisions into one shared view.

- The Dedicated Team of Pasture.io, 2026-09-25