Tensions are bubbling up at thirsty Arizona alfalfa farms as foreign firms exploit unregulated water

A blanket of bright green alfalfa spreads across western Arizona's McMullen Valley, ringed by rolling mountains and warmed by the hot desert sun.

Matthew Hancock's family has used groundwater to grow forage crops here for more than six decades. They're long accustomed to caprices of Mother Nature that can spoil an entire alfalfa cutting with a downpour or generate an especially big yield with a string of blistering days.

But concerns about future water supplies from the valley's ancient aquifers, which hold groundwater supplies, are bubbling up in Wenden, a town of around 700 people where the Hancock family farms.

Some neighbors complain their backyard wells have dried up since the Emirati agribusiness Al Dahra began farming alfalfa here on about 3,000 acres (1,214 hectares) several years ago.

It is unknown how much water the Al Dahra