For decades, Bosch Dairy in Ontario, where three generations raised cattle, was a bucolic outpost with fields of cows and rows of eucalyptus to cut the driving wind that came down the Cajon Pass.

A few years ago, Bud Bosch noticed semitrailers occasionally rumbling along the two-lane rural road by his property. Soon, dozens were kicking up dust, night and day, plying roads made for tractors.

Bosch thought he had escaped the explosion of warehouse development that has wiped out farmland and open space. But the ecommerce boom of the pandemic accelerated the land grab, and the region became ever more hardscaped into the staging point for trains and trucks carrying goods from the ports of Los Angeles and Long Beach to the rest of the nation.

There are 170 million square feet of warehouses planned or under construction in the Inland Empire, according to a recent report by environmental groups. And despite fears of a recession, demand hasn’t ebbed.

But the rapid transformation of semirural areas into barrens of concrete tilt-up “logistic parks” is encountering a backlash. Residents are questioning whether they want the region’s economy, health, traffic and general ambiance tied to a heavily polluting, low-wage industry that might one day pick up and leave as global trade routes shift.

Several Inland Empire cities, including Colton and Norco, have placed building moratoriums on warehouses, as has Pomona, which borders the region. Environmental groups are pushing Gov. Gavin Newsom to declare a state of emergency, hoping to keep new warehouses away from homes and schools, where heavy truck traffic can expose children to high levels of toxic diesel emissions that have been linked to respiratory illness.