The Mission San Xavier del Bac in Southern Arizona was built by Franciscan Monks in 1797. It's called "The White Dove of the Desert". It glows like balefire amid the mesquite.
But the mortar of its adobe brick walls is drying and cracking. And so, for five generations, a single family has been using an ancient recipe to repair and restore the mission.
It's dawn in the desert, the brilliant white walls of the mission just beginning to glow from the sun's first rays. The air is still and heavy with the pungent must of boiling cactus and smoking wood.
Daniel Morales walks along a row of growing "nopalitos", or prickly pear cactus. He's snapping the pads off the healthiest ones and tossing them in a bucket.
"So basically what we're doing now is going back to the original way that they built it and hopefully that keeps it all together for the next 200 years if not better," he said while he works.
He stirs the pads in the boiling water. When they are broken down they'll be added to lime and sand. That's what makes the mortar for the adobe bricks of the old church, an ancient recipe that can keep a building standing for centuries.
The stone church sits on bedrock; it's walls, adobe brick. The walls are always shifting, cracking. Others have tried to protect the adobe with chicken wire or concrete, but those didn't hold up. So since 1947, the Morales family has gone back to the recipe used by the monks.
Daniel is the fourth generation of his family that has taken on this project. He walks with a limp from six years of working on his knees on this church.
He gives the vat another stir. Almost done.
Sonny Morales is his father. He's 77 and is kneeling on the ground, spreading the concoction on the mission wall.
When he was a kid, his grandfather would have him bash the prickly pear with a two-by-four piece of wood. Then a Mexican taught them to cook it, break it down and bring out the polymers.
"Before cement they used anything that was available in the area, uh-huh, oh yeah," Sonny Morales said.
Now Daniel Morales and his crew use a mop-wringer. He latches it onto the side of a rusted wheelbarrow and sticks a gloved hand in the boiling water, bringing out a cooked prickly pear pad.
He stuffs it in the wringer and cranks the handle down.
"That's good stuff. Cause it's got…well, it's just good, I don't know," Daniel Morales said, laughing and fingering the sticky green goop. "It's sticky. You can tell, I don't know...it's got that stickiness to it. It helps bond the material."
A hard freeze this past winter killed much of the prickly pear cactus. So to protect and restore these walls, the Morales family has been collecting new prickly pears this winter from home gardens throughout Tucson.
Then there's generation five: Vincent Morales, 21, and a licensed real estate agent. He's spreading the mortar into the crevices between the adobe bricks of the wall.
"We need to continue to maintain it because if we don't, things will just break down and this building will just fall apart like it has been," Vincent Morales said. "So I think it would be wise to continue that after my dad and me and hopefully my kids and my grand-kids some day. So hopefully it continues."