Oregon has more open range than most people outside the state ever realize. Harney County alone covers more than 10,000 square miles, making it one of the largest counties in the contiguous United States, and a meaningful share of that territory has been worked by cattle outfits operating at a scale that is genuinely hard to picture. The largest ranches in Oregon are not just big pieces of land. They are functioning cattle operations with histories that stretch back to the 1880s, water systems that took decades to build, and herd counts that run into the tens of thousands.

What follows is a guide to Oregon’s most significant ranch landholdings, built from verified historical and property records rather than approximate figures. Where exact deeded acreage differs from total operational acreage, including leased BLM and Forest Service allotments, both numbers are noted, because that distinction matters practically for anyone trying to understand what Oregon ranching at scale actually looks like.

Deeded Acres vs Total Ranch Acreage

Most of the biggest operations in the state run on a combination of deeded private land and grazing permits covering Bureau of Land Management and U.S. Forest Service allotments. The deeded acreage is the ranch’s permanent, privately owned ground. The leased allotments can be significantly larger and are what allows the total operational footprint to reach staggering numbers.

This distinction matters because it shapes how a ranch is bought, sold, and valued, and it is the reason that total operational acreage figures can be misleading without context. The entries below note both where the numbers are documented.

1. The ZX Ranch – Lake County

Detail	Information
Location	Near Paisley, Lake County
Deeded acreage	Approximately 80,000 acres
Total operational acreage	Approximately 1.3 million acres
Founded	1880s
Current owner	J.R. Simplot Company

The ZX Ranch near Paisley is among the largest ranching operations in the United States, not just Oregon. It was founded in the 1880s by prospector John D. Coughlin, who acquired marshy land in the Chewaucan Valley under the Wetlands Act of Oregon. After Coughlin sold, the Kern County Land Company spent heavily to drain the Chewaucan Marsh and build an extensive irrigation system, making large-scale hay production possible and allowing the cow herd to grow rapidly.

By the end of the 1930s, the ranch owned approximately 230,000 deeded acres and leased an additional 1.5 million acres of surrounding range. The ZX brand was registered to the Chewaucan Land and Livestock Company in 1918. The ranch has changed hands six times since its founding and is currently owned by the J.R. Simplot Company of Idaho. Today it runs roughly 11,000 mother cows, 500 bulls, and 9,000 calves, with an annual herd of approximately 20,000 head, using deeded ground supplemented by grazing allotments from private landowners, The Nature Conservancy, the U.S. Forest Service, and the Bureau of Land Management.

2. Tree Top Ranches – Harney and Malheur Counties

Detail	Information
Location	Island Ranch near Burns, Oregon, Canyon Ranch near the Nevada border, Brown Ranch
Total operational acreage	Approximately 750,000 non-contiguous acres
Herd	Approximately 7,000 cows
Cowboys	Approximately 20 full-time employees across all divisions

Tree Top Ranches operates as several distinct ranches spread across a large geographic footprint in eastern Oregon. The three primary divisions are the Island Ranch near Burns, the Oregon Canyon Ranch near the Nevada border, and the Brown Ranch. Together, they cover roughly 750,000 acres of a mix of deeded and leased public land, making this one of Oregon’s largest multi-unit cattle operations.

The dispersed structure of Tree Top reflects how ranching in this part of the state developed over time, with operators assembling non-contiguous units across high desert terrain that could not support continuous large-scale grazing from a single location. Managing three ranches with 20 cowboys and a 7,000-head cow herd across that spread is a logistical reality that defines eastern Oregon ranching at scale.

3. The Miller-Lux Malheur River Ranch – Harney County

Detail	Information
Location	Near Crane, Harney County
Deeded acreage	Approximately 52,445 acres
BLM grazing allotment	Approximately 100,000 acres
Irrigated acreage	Approximately 1,500 acres, including 1,125 under nine center pivots
Herd capacity	1,700 breeding cows plus bulls

The Malheur River Ranch near Crane carries roots in the Miller and Lux cattle empire, which was the largest and most powerful livestock operation in southeastern Oregon during the late 19th century. Henry Miller and Charles Lux arrived in Oregon in the early 1880s, buying up herds and ranches from failing operations and controlling water sources to dominate enormous stretches of range in Harney and Malheur counties.

What Makes This Ranch Significant Today

The current operation preserves the practical logic of the original Miller-Lux approach: combining deeded private ground with a large BLM allotment, irrigated hay production to carry the herd through winter, and a location in the Malheur River basin where water and grazing conditions are far more reliable than the surrounding high desert. The 52,445 deeded acres represent one of the largest contiguous private land holdings in the state still operating as a working cattle ranch.

4. Hay Creek Ranch – Jefferson County

Detail	Information
Location	About ten miles east of Madras, Jefferson County
Founded	1873 by Dr. David Baldwin
Original name	Baldwin Sheep and Land Company
Peak livestock	50,000 sheep
Current status	One of the largest continuously operating ranch holdings in central Oregon

The Hay Creek Ranch is one of the oldest continuously operating large ranches in Oregon, established in 1873 by Dr. David Baldwin as the Baldwin Sheep and Land Company about ten miles east of Madras. Baldwin was one of the first ranchers in Oregon to raise alfalfa for winter feed and bred Merino sheep from stock brought from Vermont. The Dalles-Prineville freight and stagecoach lines ran through the ranch headquarters until approximately 1912, making Hay Creek a geographic anchor for central Oregon’s early agricultural economy.

At its peak, the Baldwin operation ran 50,000 sheep on the central Oregon range. The ranch changed hands in 1883 and went through several ownership transitions over the following century, but it has remained one of the most recognized large landholdings in central Oregon. For over a century it has held its place as one of the largest ranch operations in the state, though its acreage has shifted through various consolidations and sales.

5. Muddy Ranch – Wasco and Jefferson Counties

Detail	Information
Location	Muddy and Currant Creek drainages, Wasco and Jefferson Counties
Peak acreage	Nearly 70,000 acres
Current deeded acreage	Approximately 64,280 acres
Current owner	Young Life (nonprofit youth organization)
Notable history	Operated as Rajneeshpuram from 1981 until the mid-1980s

Muddy Ranch in Wasco and Jefferson counties has a complex and layered history. The land was first noted in the 1860s by Joseph Sherar, a well-known Oregon explorer and road-builder, and the stagecoach station at the joining of Muddy and Currant Creeks became a waypoint on the Dalles-Canyon City route. By the early 20th century, the ranch had grown to nearly 70,000 acres under the Prineville Land and Livestock Company and later the Hahn family, operating primarily as a sheep operation in an era when central Oregon ranching was dominated by wool production.

The Ranch’s More Unusual Chapter

In 1981, Muddy Ranch was purchased by followers of Bhagwan Shree Rajneesh, an East Indian spiritual leader, who renamed it Rajneeshpuram and built a settlement there that briefly housed thousands of people. After that chapter ended, the ranch passed through several more owners before being purchased by Young Life, a nonprofit youth organization, which operates it today at approximately 64,280 deeded acres. While large Oregon sheep outfits saw massive contractions as synthetic fibers and Australian wool reshaped the market in the 1950s and 1970s, Muddy Ranch has largely retained its historical footprint.

6. Big Canyon Ranch – Wallowa County

Detail	Information
Location	Near Joseph, Wallowa County
Deeded acreage	6,400 contiguous acres
Public roads	None through the property
Terrain	Wallowa Mountains, timbered drainages, summer grazing
Primary use	Cattle, elk habitat, recreation

The Big Canyon Ranch near Joseph in Wallowa County covers 6,400 contiguous deeded acres with no public roads running through the property. Ten square miles of private, unbroken ground in Wallowa County is a genuinely rare configuration in a part of Oregon where public land and private holdings are interspersed throughout the mountains and canyon country.

Wallowa County’s ranch country differs from the high desert operations in Harney and Lake counties. The terrain runs into the Wallowa Mountains, the drainages hold water more reliably, and the property often supports timber, elk habitat, and summer grazing in combination rather than the year-round open-range cattle model common across the southeast.

7. Puckett Ranch – Harney County

Detail	Information
Location	South of Burns, Harney County
Deeded acreage	Approximately 5,445 acres
State lease	240 additional acres
Additional grazing	BLM grazing permits
Terrain	High desert, Great Basin

The Puckett Ranch near Burns covers approximately 5,445 deeded acres with an additional 240-acre state lease and BLM grazing permits, located in the high desert country south of Burns. This is the landscape that shaped Oregon’s ranching identity more than any other: vast, dry, and reliant on the combination of deeded water sources and public grazing allotments that large-scale cattle operations require to function in the Great Basin.

The Puckett Ranch is smaller than the century-old giants that defined Oregon ranching in the late 1800s, but it reflects what working outfits in Harney County actually look like in practice today, combining a private deeded core with BLM and state lease acreage to reach a viable operational scale.

What Oregon’s Largest Ranches Have in Common

Looking across the entries above, a few patterns show up consistently across Oregon’s biggest operations.

They are almost entirely east of the Cascades, concentrated in Harney, Lake, Malheur, Jefferson, Wasco, and Wallowa counties.
The most significant ones combine deeded private land with substantial BLM and Forest Service grazing allotments.
Water control, specifically who holds the water rights and when those rights were established, has historically determined which operations could grow and which could not.
The biggest outfits tend to have multi-decade or multi-generational ownership histories, because assembling that much land and water takes time.

That relationship between land, water, and scale is something we work through with buyers and sellers across Oregon’s ranch country regularly. If you are evaluating Oregon ranches with a serious operational use in mind, understanding the difference between deeded acres and total permitted acres is the first practical question to resolve, and our guide on the difference between a ranch and a farm covers the operational and definitional distinctions that matter when you are comparing property types. For anyone drawn to Oregon specifically for its open country and scale, our piece on what Oregon is known for covers the broader land and landscape context that makes this state unusual, and for those who want to understand Oregon hunting seasons on ranch ground specifically, that piece covers the unit-specific framework that shapes recreational use on large eastern Oregon properties.

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