At one time, people fled to Tucson to escape pollen, where the desert was considered a deterrent against allergies.
As early as 1929, a brochure for a local sanatorium promised treatment for sinusitis and other respiratory ailments, proclaiming, "The desert is God's great health-giving laboratory."
Changes in the landscape since then and have forced many residents to change their minds.
"You always hear, 'Hey, the desert's great for your sinuses," says Cast, who had hoped the desert landscape would alleviate her allergies when she moved here from Tennessee in February. Instead she found herself surrounded by pollen-producing plants.
"There's a lot of green stuff out here. There's millions of plants," she says. "I don't know what all the stuff is, but there's a lot of green stuff."
"My kids didn't have allergies before we came here, my husband never had allergies until we came here. Everybody I know who's come here from somewhere else has developed allergies." sniffs Kelly, a Tucson resident since 1976.
Ironically, those who flocked here for health reasons over the decades are among those to blame for the sneezing and wheezing of today's Tucsonians.
By the late 1800s, the Southern Pacific Co. had a rail line running through Tucson, and with the so-called health-seekers came the farmers and ranchers and miners. They came from the East, the Midwest, from California and Europe to make the desert their own.
Part of that meant turning the desolate swath of land into an oasis of sorts.
"If you're going to live here, you want to try to make it comfortable," says Mark Sneller, an allergy researcher who examined pollen changes in Tucson from the 1940s through the 1980s. "It didn't take a rocket scientist to realize that a lawn reflected less heat than hard-packed earth."
Bermudagrass was introduced for pastures and lawns. European olive trees, brought to the United States in the 18th century by Spanish missionaries, were planted for fruit and shade. Later, Tucsonians imported Chinese mulberry trees for shade.
Few knew the nonnative plants would spawn another species once alien to the desert: allergies.
By the 1980s, pollen counts had increased tenfold compared with the 1940s, Sneller says. In 1984, the county outlawed the sale of olive and mulberry trees and mandated that Bermudagrass be cut regularly, threatening violators with fines.
Tucson, one-time haven for health-seekers, became home to the first pollen-control ordinance in the nation. Other Southwestern cities followed, including Albuquerque, El Paso and Las Vegas.
Today, about half of the 840,000 people who live in the Tucson area suffer from allergies twice as high as the national average, Sneller says.
A twice-weekly newspaper column dispenses advice on avoiding allergenic plnts and substances.
A respiratory radio show optimistically titled "Breathing Easy" is broadcast weekly.
And because the pollen ordinance did not require trees already in the ground to be removed, the misery continues.
That is the legacy of the desert pioneers.
"They tried to take a desert and make it a tropical area," Kelly says, pausing to clear her irritated throat before finishing. "It doesn't work."