Terrain · Select a property, draw a box or polygon, or upload a boundary

Landform classification map for Oregon land

A landform classification map labels every part of a property as one of ten landforms, from peaks and ridges down to hollows, valleys and pits, using the geomorphons method on the USGS 3DEP lidar elevation model.

It reads the shape of the land at a glance: exposed ridges, well-drained spurs, sheltered hollows and the draws where water and cold air gather.

Free to run · pay to download

See the full result on the map free, with no account. Download the landform map as a GeoTIFF with a pass: US$29 for 24 hours, US$99 for 30 days or US$399 for 12 months, a one-off payment in US dollars that never renews. Every download on the site is included while the pass lasts.

Who uses this

  • Farmers, ranchers and foresters. Match planting and livestock to exposed ridges and sheltered hollows.
  • Ecologists and GIS analysts. Get a geomorphon map without setting up GIS.

When to use it

  • Reading the shape of a property quickly: where the ridges, draws and flats are.
  • Finding sheltered hollows, exposed ridges or well-drained spurs for planting and livestock.
  • Understanding drainage and slope stability patterns before walking the ground.

Tools for your job

Landforms is one step in a bigger question. These are the jobs it helps with, and the tools that go with it.

For the job: Drainage, flooding and wet ground

Where does the water go, and where will it sit?

  1. 1.Water & Drainage — The drainage channels across an area, and where water ponds once low spots fill.
  2. 2.Wetness Map — Which parts of a field the shape of the land keeps wet.
  3. 3.Catchment — All the land that drains to one culvert, draw or low corner.
  4. 4.Landforms (this tool) — Hollows, valleys and footslopes at a glance: where water gathers.

For the job: Farms, ranches, orchards and timber

Which ground suits which use?

  1. 1.Slope & Aspect — Equipment limits and erosion-prone slopes.
  2. 2.Sunlight — Frost pockets and shaded slopes in winter.
  3. 3.Wetness Map — Wet-tolerant planting in the blue, drought-tolerant on the tan.
  4. 4.Landforms (this tool) — Exposed ridges, sheltered hollows and well-drained spurs.

How to use it

  1. Select a property, draw an area or upload a boundary.
  2. Set the neighborhood radius. Small radii pick out field-scale features; large radii describe the hill as a whole.
  3. Run. Each landform has its own color, and the panel gives each one’s share of the area.

Step by step: Mount Hood

We classify the shape of Mount Hood’s south side with a medium neighborhood radius.

1.Zoom to the area and set the neighborhood radius. A medium radius reads the ridges and canyons; a small one would pick out banks and ditches.

2.Run the analysis. The panel gives the share of slope, spur, hollow, valley and ridge in the area.

3.Zoom in to follow the spurs (well drained, exposed) and the hollows between them (where water and cold air gather).

What it showed

  • Run the same area at a small and a large radius; the classes change, because landform depends on the scale you look at.

How it works

The tool looks out from each cell in eight directions to the chosen radius and records whether the ground rises or falls in each. The pattern of rises and falls is matched to one of ten landform types, a method known as geomorphons.

Reading the results

Ridges and peaks are the high, exposed ground; valleys, hollows and pits collect water; spurs and shoulders are the well-drained slopes in between.

The same hillside can read differently at a small and a large radius. That is expected: landform depends on the scale you look at.

Limits and caveats

  • Radius from 16 ft to 820 ft. Areas are sampled more coarsely than contours, so the smallest features can be missed on large areas.
  • Where lidar has not been flown, the USGS 3DEP model falls back to its 1/3 arc-second layer, about 33 ft per pixel, and downloads state what share of the area came from it. That coarser model is not fit for site-scale decisions. DOGAMI reports about 99% of Oregon covered by at least one lidar project. The fallback is rare.

Data and attribution

Results come from the USGS 3D Elevation Program (3DEP) bare-earth elevation model: lidar at 3.3 ft per pixel where it has been flown, and the 1/3 arc-second model, about 33 ft per pixel, elsewhere, with elevations above NAVD 88. The tools with a surface option (Sunlight, Viewshed, Sightline, Object Heights) read DOGAMI’s statewide digital surface model of trees and buildings.

USGS 3DEP elevation data and USGS maps are U.S. Government works in the public domain: you may use the results, including commercially. A credit to the USGS 3D Elevation Program is appreciated, and every file you download carries it. DOGAMI lidar products are published by the State of Oregon; credit "DOGAMI / Oregon Lidar Consortium". County taxlot boundaries are the assessor's GIS data, not surveys, and each county publishes its own disclaimer, shown with the parcel. The aerial basemap is from Esri and follows Esri's terms; it is not included in downloads.

Questions

What radius should I use?

Small radii, a few dozen feet, pick out field-scale features. Larger radii, up to 820 ft, describe the hill as a whole. The same slope can read differently at each scale.

Ready to try it?

Open Landforms on the map →

Free to use, no account. The analysis runs in your browser on public-domain USGS 3DEP data. Downloading the results needs a pass: see pricing.