Arizona “Trigger” Water Trap

Arizona’s Sonora Desert is known for its rough terrain and wild cattle.  For years, one way that stock growers have gathered their cattle in this rough country is to use a device called a “trigger” on their water traps.  Where the “trigger’ idea originated is uncertain; however, it is still used in many lower desert areas today. A trigger is built on a permanent source of water such as windmills, wells, springs, or “tanks” as they call dirt ponds in Arizona.  A corral is set up with an opening where the trigger is built to let cattle into the water.  When the cowman doesn’t need to catch the cattle, the trigger is left open, and the cattle can move in and out of the trigger opening into the fenced water lot.  Sometimes there is a second trigger on the opposite side of the corral where the cattle can go out, so they learn to trigger in and trigger out.  Protein blocks, salt and sometimes hay can be placed inside the corals to lure the cattle in.

            The builder of the system pictured believes that wood poles on the trigger work better than pipe, because the wood does not become bent.  Metal pipe becomes bent up, especially in pens where bulls are fighting.  This 45’x45’ holding pen is reinforced with shaggy bark cedar stays.  The trigger poles are 10’ lodge poles.  Pine or cedar works best for the poles.  The longer the trigger poles, the easier cattle can pass through.    For horned cattle, the chains holding the trigger poles can be set farther back on the poles, up to 60” wide for horned cattle, so they don’t get their horns caught.  The chains are set wide and then gradually set narrower as the cattle become accustomed to entering through the trigger gate.  The cross bar above the trigger is 7’ high so that a mounted rider can enter the pen through the opening.

When it is time to gather cattle, the trigger is set to allow cattle to push through the trigger into the water lot.  The cattle are unable to go back out because the trigger closes behind them.  Calves can be branded in the sorting pen.  A trailer can be backed into the wings at a trailer gate situated at the out-trigger and the cattle loaded.  The cows and bulls can be sorted and turned out after they have been worked.

           This set up allows livestock people to work cattle in a large rugged area without the need for many days of hard riding after cattle in rough country.  This capture system works best where there is very little live water on a range; however, cattle can be caught even with other waters in the area, if they are baited in with salt, mineral blocks, and hay.  The system also works to gentle cattle down.  They become accustomed to the corral, coming and going for feed, minerals, and water and being around people on horseback.

This system can be used anywhere there is limited water.  We also helped construct one in the desert country of Nevada which is also pictured below the diagram.  You can see from the photos the poles can be of several materials.

A version of this article by Lee Raine appears in the August 2002 issue of the Western Horseman Magazine.

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