People know Idaho for its vast open spaces, from mountains, grasslands, and forests to potato farms and sheep pastures.

But this picture-postcard image might not last, thanks to population growth and accompanying sprawl. Between 1980 and 2020, Idaho nearly doubled its population — and it’s on track to add 800,000 people over the coming decades. Predictably, developers have devoured croplands and forests to construct the new housing, offices, and roads to accommodate all these new residents.

Idahoans aren’t happy about these changes. A new poll confirms that most voters want to end the pattern of migration that’s destroying their fields and forests, crowding their parks, and changing their way of life.

The Gem State started off as the haunt of wolves and bears — plus a few enterprising farmers. Back in 1890, the year Idaho gained statehood, barely 89,000 Americans called the state home.

But over the years, that’s changed. Idaho now has more than 1.8 million people — after adding between 270,000 and 290,000 new residents per decade over the last 150 years. Today, measured by percentage growth, the Gem State is expanding faster than any other state.

Rapid population growth has led directly to urban sprawl. With so many newcomers to house, employ, and provide for, developers have been busily erecting new residences, schools, strip malls, and offices across Idaho’s once-pristine landscape — replacing cows and potatoes with cement strips and yards. Through 2017, Idaho sacrificed more than 1,400 square miles of open space to sprawl, according to an environmental impact study I recently co-authored.

Population growth accounts for much of that land-loss. Since 1982, Idaho has lost nearly 450 square miles of open space to development caused by adding new residents. That’s an area larger than the state’s 15 biggest cities and towns combined. Between 2002 and 2017, a whopping 83% of sprawl in Idaho counties derived from more residents, as opposed to people “consuming” or “converting” more rural land — by, for instance, building bigger houses on bigger parcels.

Gem State residents broadly dislike this growth. According to a new poll, nearly three-quarters of likely Idaho voters want their state’s population to expand more slowly (47%) or get smaller (23%). And 67% think that adding 800,000 more residents over the next few decades, as projected, would be a net negative for their state.

That’s because Idahoans recognize how sprawl reduces their quality of life. Nearly nine in 10 likely voters (87%) say their parks and natural areas have gotten more crowded in recent years. Around half (48%) think Idaho has converted too much land into cities, housing, and highways.

Gem State voters are especially worried sprawl will eat into agriculture. Idaho has more than 25,000 farms and ranches, with 2.1 million cattle. The state ranks among America’s top food producers — cranking out jaw-dropping quantities of potatoes, wheat, barley, peas, onions, lentils, apples, plums, cherries, and cheese. Agriculture and food and beverage production account for 18% of sales in Idaho every year.

So it’s no wonder Idahoans value their fields and farms. An overwhelming 95% believe it’s “important” to protect farmland from development so Americans can keep producing their own food — with eight in 10 (81%) saying it’s “very important.” Nearly three-quarters (73%) oppose diverting water away from irrigating farmland to support a growing population. No wonder: some wells in Ada County have actually run dry, thanks to the increased demands of a growing population.

The sprawl won’t end without government action. Bad policies in other states are actively driving residents to Idaho. Take Gavin Newsom’s California. In 2019 and 2020 alone, nearly 18,000 people left California for Boise alone. There’s even a website, “ExitCalifornia.org,” encouraging Californians to make the trek — and dangling Idaho’s comparatively low cost of living as an incentive.

A half-century of lax immigration policies have also contributed to the sprawl. About 75,000 immigrants currently live in Idaho, and another 52,000 people who are the children of immigrants also call the state home.

Idahoans support policies to slow future growth. A clear majority (56%) think local and state governments in Idaho should restrict development so it’s harder for people to move from other states, while 54% support reducing immigration.

Voters want Idaho to remain the Gem of the Mountains. It’s up to policymakers to ensure that happens.