Honest Cattle · Range Tools for Ranchers
Read Your Own Ground
A plain-English guide to checking your ranch’s range condition and 20-year trend — for free — using the USDA’s Rangeland Analysis Platform (RAP). You supply the boundary; the satellites do the rest. We’ll show you how to set it up and, just as important, how to read what comes back.
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Twenty-some years of satellite data on your grass already exists, it’s public, and it’s free. The catch is that it comes back as charts and percentages, not decisions. This guide walks you through running the analysis on your deeded ground and then translating the numbers into the only questions that matter: Is my forage base getting stronger or weaker? Am I carrying the right number of cattle? Where should I be watching?
First, the lay of the land
1. What RAP is — and what it can’t tell you
RAP turns 30+ years of Landsat satellite imagery into yearly estimates of what’s growing on rangeland, anywhere in the lower 48. For any piece of ground you outline, it reports the percent cover of six things — perennial grasses & forbs, annual grasses & forbs, shrubs, trees, bare ground, and litter — plus an estimate of herbaceous production (pounds of forage per acre) going back to the 1980s.
You’ll use two free tools on the site:
- The RAP Web Map — draw or upload your ranch and get the cover-and-production trend lines. This is where the 20-year story lives.
- The Production Explorer — feed it the same ground and it compares this year’s forage to your long-term average and sketches stocking rates.
Before you start
2. What you’ll need
- A computer with a web browser (this works best on a desktop or laptop, not a phone).
- A rough idea of where your deeded ground sits — enough to recognize it on a satellite map.
- Optional but better: a boundary file (shapefile or KML) if your FSA office, a consultant, or your own mapping app already made one.
- Optional: your owner name as it reads on the tax rolls, if you want to pull parcels from Montana Cadastral.
The one thing only you can supply
3. Step 1 — Get your ranch boundary into RAP
RAP doesn’t know where your ranch is. Everything depends on giving it an accurate outline. There are three ways to do that, listed easiest to most precise. Pick the one that fits what you’ve got.
1. Deeded-only, or your whole grazing footprint? Decide whether you’re analyzing just your deeded acres or the full deeded-plus-leased ground you actually run cattle on (BLM, state, or private lease). Both are valid — just be clear which one you’re looking at, because the trend means different things. Many ranchers run it both ways.
2. Leave out the hayfields and pivots. RAP’s production numbers are built for rangeland. Drawn over irrigated hay, pivots, or farmed ground, the figures aren’t valid. Outline grazing land only, and cut around the obvious green circles and hay meadows.
Most ranchers can spot their own deeded ground from the air. If you don’t have a boundary file, this is the fastest path and it’s plenty accurate for reading trend.
- Open the RAP Web Map.
- Zoom and pan the satellite map to your ranch. The hybrid/satellite view helps you trace along section lines, fences, creeks, and the breaks you already know.
- Click Draw Features. The default is a polygon (an area). Click point-to-point around your boundary, clicking more often on the curvy stretches to hug the line.
- Double-click to finish the shape. The Analysis Panel opens on its own.
- Click Calculate Time Series. In a few seconds your charts appear.
Tip: you can draw more than one piece — a separate polygon for a leased unit, say — and click each one to see its own trend.
If your FSA office, NRCS, an agronomist, or a mapping app (onX, Avenza, etc.) gave you a boundary, use it — it’s exact to the property line.
- You need a zipped shapefile. That’s a single .zip containing at least four files with the same name:
.shp,.shx,.dbf, and.prj. (If a file came as a KML, most mapping apps can export a shapefile, or your FSA/NRCS office can.) - In the RAP Web Map, click Upload shapefile and pick your .zip. The map zooms to your ground.
- Click your ranch outline, then Calculate time series.
If the upload won’t take, the usual culprit is a missing .prj file or files zipped inside a folder instead of loose. RAP has a short shapefile troubleshooting guide.
This is the Montana-specific path, and it’s the same Cadastral tool we link on the Honest Cattle county pages. It’s the way to capture every parcel you own — including the scattered 40s and the piece across the county road — by your name on the tax rolls.
- Open Montana Cadastral (svc.mt.gov/msl/cadastral) and search by Owner. Use the
%symbol as a wildcard if your name reads several ways on the rolls (e.g.Adams%). - Note the parcels that are yours — Cadastral shows owner, acres, and geocode for each. This confirms exactly what ground is in your name and where it sits.
- Two ways to get it into RAP from here:
- Quick: keep Cadastral open beside RAP and use it as your reference while you hand-draw the boundary (Option A). Your parcels are now exact targets to trace.
- Exact: for a true property-line boundary, the Montana State Library publishes parcel data by county as downloadable shapefiles. Pull your county’s parcel layer, isolate your parcels by owner, dissolve them into one outline, and upload that (Option B). This is GIS work — if that’s not your world, this is exactly the kind of thing the Honest Cattle concierge report can do for you.
Reminder from above: once you have all your deeded parcels, decide whether to add leased units, and trim out hayfields and pivots before you analyze.
The 20-year story
4. Step 2 — Run the cover analysis
Once you’ve clicked Calculate Time Series on your boundary, RAP draws trend lines for each cover type from the 1980s to last year. This is the heart of it — the long view of what your grass has been doing.
Find the lines that matter
The two to watch first are perennial grasses & forbs (your bread-and-butter forage) and bare ground (the inverse — exposed dirt). You can toggle cover types on and off to declutter the chart.
Look at direction, not just this year
One year tells you about the weather. The slope across 15–20 years tells you about your ground. Is perennial cover holding, climbing, or grinding down? Is bare ground creeping up? Ignore the year-to-year zigzag (that’s rainfall) and follow the overall tilt.
Glance at annual grasses
A rising annual grasses & forbs line can flag cheatgrass and other invaders muscling in — forage that’s here early and gone by summer, and a fire risk. A little is normal; a clear upward march is a warning.
Save your numbers
Hover the lines to read values, or export the data to a spreadsheet from the Analysis Panel so you can compare year to year and keep a record. Jot down the start value, the recent value, and the direction for perennial cover and bare ground — you’ll use those in the interpretation section below.
Forage & carrying capacity
5. Step 3 — Run the production analysis
The Web Map shows production too, but the Production Explorer is the better tool for the stocking question — it puts this year’s forage in the context of your own history.
Open the Production Explorer and set your baseline years
Launch the Production Explorer. First, set the start and end years for your long-term average. The default 2001–2020 works for most operations; you can choose any window between 1986 and 2020. This 20-year band is the “normal” everything else gets measured against.
Load your ranch
Upload the same zipped shapefile you used in Step 1 (or the RAP 16-day biomass CSV if you exported one). Same boundary, same rules — rangeland only, hayfields and pivots left out.
Work the three tabs
Current production shows this year so far against your long-term average — are you running ahead or behind a normal year? Historical production shows the full record, good years and droughts alike. Stocking rate estimates carrying capacity across the period you chose.
The part only a rancher cares about
6. How to read your results
Here’s where the charts become decisions. RAP hands you four readings worth your attention. This table is your translator.
| What RAP shows | What it means for your grass | What to do about it |
|---|---|---|
| Perennial cover trend (grasses & forbs over 15–20 yrs) | Rising / flat = your forage base is holding or building. Falling = the engine of your ranch is weakening, often slowly enough to miss year to year. | A downward slope is the single most important signal here. It usually points to grazing pressure, drought stress, or both — and it’s the thing to act on first. |
| Bare ground trend | Rising = more exposed soil. That means less forage, faster runoff, more erosion, and ground that dries out and bakes harder in a drought. | Rising bare ground almost always mirrors falling perennial cover — same problem, seen from the dirt’s side. Watch where on the ranch it’s worst. |
| Annual grass cover | Rising = invaders (cheatgrass, medusahead, annual brome) gaining ground. Early feed that’s gone by summer, and a real fire load. | A clear climb is a flag to scout those areas on the ground and think about timing, rest, or treatment before they take over. |
| Production vs. history percentile | Where this year’s forage falls against your 20-year record. High percentile = a strong year. Low percentile = a short year, early. | This is your early-warning gauge for drought response — it tells you you’re behind before the grass runs out, while you still have options. |
A worked example: what “down 6 and up 4” actually means
Say you pull your numbers and they read like this:
BARE GROUND ……….. 18% (2003) → 22% (last yr) ▲ up 4 pts
ANNUAL GRASSES …….. 3% (2003) → 4% (last yr) ~ steady
PRODUCTION ………… 38th percentile this year (below average)
In plain terms: over 20 years your perennial forage base has thinned by about an eighth, and the ground it gave up has gone to bare dirt, not weeds (annuals held steady — good news). It happened slowly — about a third of a point a year — which is exactly why it’s easy to miss from the seat of the truck. And this year you’re coming in below your own average.
The read: this isn’t a crisis, but it’s a clear, multi-year softening of your forage base, and you’re entering a below-average year on top of it. That combination is a signal to ease off stocking a touch, plan more recovery time on your hardest-hit pastures, and figure out where the bare ground is concentrating so you can focus your attention. Caught now, this is a management adjustment. Ignored for another decade, it’s a capacity problem.
From charts to the corral
7. Turning the numbers into decisions
Stocking
Let the perennial trend set your long-run carrying capacity and the production percentile fine-tune this year. A falling perennial line over years says your sustainable numbers may be drifting down, regardless of any single good summer. A low percentile early in the season says this year will be short — adjust before you’re forced to.
Drought response
The production percentile is the gauge to watch in spring and early summer. When it comes in low and early, you’ve got lead time — that’s when destocking, early weaning, or lining up extra feed is cheap and orderly instead of a fire sale in August.
Where to watch
If you ran separate polygons for different pastures or units, compare them. The piece with the steepest perennial decline or the fastest-rising bare ground is where your boots and your management changes will earn the most. RAP can’t fix a pasture, but it can point you to the one that needs you.
Straight talk
8. The honest cautions
- It’s an estimate, not a measurement. RAP averages satellite pixels. It’s strong on trend and direction, looser on any single year’s exact pounds. Ground-truth what surprises you.
- Boundary quality is everything. A sloppy outline that catches a county road, a neighbor’s pivot, or a stretch of timber will muddy your numbers. Tighten the boundary before you trust the trend.
- Rangeland only. The production figures don’t hold over irrigated, hayed, or farmed ground. Keep those out.
- Read trend over years, not noise over seasons. The year-to-year wiggle is mostly rainfall. The multi-year slope is your ground.
- Use it alongside what you already know. RAP is a second set of eyes from 400 miles up. Your own records, your range, and a hand on the grass still win ties.
Want us to do this one for you?
If the boundary work isn’t your idea of a good evening — especially the Cadastral-to-shapefile step — Honest Cattle can run your ranch and send back a one-page “Your Ranch: Range Condition & Trend” report: the same RAP analysis, your numbers, read in ranching terms, branded and ready to file or share with your banker, lessor, or the next generation.
Reach out through honestcattle.net.
The Rangeland Analysis Platform is a free public tool from the USDA Agricultural Research Service and partners (rangelands.app). Montana parcel data comes from the Montana State Library Cadastral program (svc.mt.gov/msl/cadastral). Honest Cattle is not affiliated with USDA or the State of Montana; we just help ranchers use these tools. RAP figures are satellite estimates and should be paired with on-the-ground knowledge — they are not a substitute for professional range or financial advice.
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