Understanding Oregon's Land Classifications

Contributed by RNW Staff

For many years, RNW has been engaged in conversations on Oregon's land use, and we’ve often found that the same words can mean very different things to different people. For example, terms like "farmland" and "agricultural land" are used interchangeably in these conversations, but as we explain below, these terms can refer to different categories of land.  

That ambiguity has consequences across policy debates on renewable energy siting, housing development, conservation, and agricultural protection, as we are all wrestling with the same underlying questions: how is each category of land defined, how do different definitions affect perceived value, and what can different categories of land be used for. To better understand these questions, we dug in. Here’s what we found.

The Challenge: Multiple Systems with Overlapping Definitions 

Oregon's agricultural land is classified through several systems that operate simultaneously. These include federal soil classifications, federal agricultural tracking categories, and Oregon’s own state definitions. Each system measures something different, and understanding where they overlap – and don’t overlap – is essential for anyone trying to determine how land can be used.

The Federal Foundation

At the federal level, land is evaluated through two distinct lenses: what the land is physically capable of supporting and how the land is actually being used. The Federal Land Capability Classification System focuses on inherent soil and landscape characteristics, regardless of current activity. By contrast, Federal Agricultural Tracking Systems document real-world agricultural use and investment, such as crop production, irrigation, and farm income. Together, these two separate systems paint a picture of agricultural land across the country. But because they answer different questions, they don’t offer a single vision of how a specific area of land might best be used.  

Land Capability Classification: The Natural Resources Conservation Service developed the Land Capability Classification (LCC) system in response to the 1930s Dust Bowl, when the federal government launched widespread soil surveys to identify which land could support agriculture and prevent future land degradation. The LCC system is descriptive but not prescriptive as it inventories soil capability based on physical properties. It does not recommend or restrict land uses.

In the LCC system, land is rated from Class I to Class VIII, reflecting its ability to support agriculture. Class I soils have few limitations: they're deep, fertile, well-drained, and on gentle slopes. As class numbers increase, limitations such as erosion risk, drainage issues, or steeper slope become more significant. For example, because of issues like steep terrain or exposed rock, Class IV soils can only support crops with careful management, while Class VIII land cannot support traditional agriculture at all. While these soil capability classifications have changed little since the 1960s, they continue to form the foundation for both federal tracking and Oregon's state-level land use decisions.

Federal Agricultural Tracking: Separately, the U.S. Department of Agriculture tracks how land is actually used. For example, the category "Land in Farms" includes property that generates, or could generate, at least $1,000 in annual agricultural sales. Note that this is an economic threshold, not a soil quality measure. The category "Croplands" track land actively used for crop production in a given year. And "Irrigated Lands" identify parcels with irrigation infrastructure, which is relevant because irrigation can make marginal soils productive. These and other categories can overlap with soil classifications, but they measure use and investment rather than inherent capability. For example, irrigated land can include poor-quality soils made productive only through major water infrastructure, while high-quality soils without irrigation may be less viable in arid regions. This overlap shows why it is not always true that “irrigated land equals good farmland” or “Class V soils are always unsuitable for farming.”

Oregon Classifications 

Oregon classifications build on the federal Land Capability Classification (LCC), but add state-specific definitions that directly influence land use decisions. Oregon's agricultural land categories, particularly High Value Farmland and Exclusive Farm Use, were developed decades after the federal LCC system with a specific purpose to guide and restrict land use decisions based on that soil capability data.

It's important to note that Oregon defines agricultural land differently in Eastern and Western Oregon. In Western Oregon, agricultural land only includes Class I–IV soils. In Eastern Oregon, the definition expands to also include Class V and VI soils, reflecting the region’s varying soil capability. Without the additional soil categories, much of Eastern Oregon would not receive an agricultural designation.

High Value Farmland (HVF) is intended to protect Oregon's most productive agricultural land. Originally focused only on Class I and II soils, the definition has expanded over time to include unique soils suited for specialty crops and vineyards. HVF receives the strongest protections from development under Oregon law, reflecting its role in safeguarding the state's most productive farmland.

Exclusive Farm Use (EFU) is a zoning designation that considers soil categories but includes other factors as well. This creates important distinctions: land with poor soils (such as Class VI or VII) may still be zoned EFU, but only if it's suitable for grazing or needed to support adjacent farm operations, while high-quality soils outside urban growth boundaries are typically zoned EFU regardless of current use. EFU zoning is an Oregon-specific land category designed to maintain agricultural capability, prioritizing the land's potential for farming over its actual current use, or any other possible uses. 

Oregon defines 'nonarable soil' as Class V–VIII soils that have never been irrigated. The 'never irrigated' criterion matters: irrigation can transform marginal soils, so land with existing irrigation infrastructure is excluded. This category identifies land genuinely unsuited for conventional farming. However, nonarable soils may still be protected agricultural land; Class V–VIII soils that are adjacent to, or intermingled with, Class I–IV (or I–VI in Eastern Oregon) soils within the same farm unit are still considered agricultural land, even if they are not cropped or grazed. 

How These Systems Overlap 

Because these classification systems measure different things, a single parcel of land can fall into multiple (and sometimes conflicting) categories. For example, a parcel of Class II soil in the Willamette Valley would almost certainly be considered agricultural land under Oregon's Western Oregon definition and designated as High Value Farmland based on its soil quality. Based on its soil quality alone, it would also likely be zoned Exclusive Farm Use. If it were actively farmed, it would also be tracked federally as Land in Farms, and possibly as Croplands. In this example, soil capability, current use, and zoning protections all align.

On the other hand, a Class VI parcel in Eastern Oregon used for cattle grazing illustrates how these systems can diverge. Despite its lower soil capability, the land would still qualify as agricultural land under Eastern Oregon's broader definition and could be zoned Exclusive Farm Use based on its suitability for grazing. Federally, it would be counted as Land in Farms, even though it would not qualify as Croplands and would not be considered High Value Farmland at the state level.

These overlaps mean that terms like "farmland" or "agricultural land" can refer to very different realities depending on the system being referenced. A parcel may be protected – or not – because of its soil quality, its current agricultural use, or a zoning decision – each rooted in a different policy goal.

It's also worth noting that most EFU-zoned land was designated as such when counties adopted their original comprehensive plans in the 1970s, meaning the zoning often reflects a historical policy decision rather than a contemporaneous evaluation of soil quality or current agricultural use.

Why This Matters 

Land use debates in Oregon, whether about housing, energy development, agriculture, or conservation, often involve people talking past one another while using different classification systems to argue why land should be used in a certain way. Developers may focus on soil capability, agricultural advocates on EFU zoning, and regulators on HVF protections.

Understanding what each system measures, and what it doesn't, helps clarify what's actually at stake in land use decisions, and why disagreements can arise even when everyone is using the same words. In the next blog in this series, we’ll zoom out from land classifications themselves and explore why developers, particularly in renewable energy, often consider using agricultural land for development.