FIRE ON THE MESA

Four-wheel-drive trucks, utility vehicles, private and government fire trucks, and a helicopter sat helter-skelter along Bloody Basin Road. They and the people who drive them were waiting for a fire to break out. They topped out at 115°, scorching wouldn't have long to wait. but not too unusual for an Ari"The fire crews will start zona summer day. burning the grass as soon as The heat and the dry grass conditions are right," said Patti produced an incendiary comFenner, a Tonto National Forest bination, a condition the habiemployee out of the Cave Creek tat specialists from the Tonto Ranger District. "Once they and Prescott national forests back burn a buffer zone, they'll wanted. ignite the grass along the road "We're trying to mimic a natand let the wind carry it back ural fire, one caused by lightto the burned-out buffer zone. ning," explained Fenner. "This "When we plan a burn like is the right time, just before this," she continued, "the fire the summer monsoon rains, people study wind patterns, the when the grasslands historicalamount of grass and other fuel, ly burned. We have tried burnthe temperature, and the humiding the grasslands in the winter, ity. And they're pretty good at spring, and fall, but we can't get predicting where the fire will go." the results we can get when As noon approached, the temburns take place during the hotperature reached toward 100° test times of the year." F. In Phoenix that July day, it Fires benefit the grasslands

Reviving Grass

(LEFT) Open areas of short grass give pronghorn antelope the best visual defense against mountain lions and other predators. By eliminating brushy hiding places, prescribed burns bring antelope back to areas they might have avoided. PAUL AND SHIRLEY BERQUIST (RIGHT) The Agua Fria Grasslands stretch from the high plateau reaches of Prescott Valley south to the distant New River Mountains. JERRY SIEVE because they get rid of the old growth that's so dry and woody cattle won't touch it, according to Fenner. They also burn out the invasive plants like mesquite, snakeweed, junipers, and catclaw that usurp more and more of the grasslands.

Fire serves as the prime restoration tool used by the Agua Fria Grasslands Coalition, a group of some 80 individuals, ranchers, organizations, clubs, and government agencies concerned with protecting and improving the high-desert grasslands of which the Agua Fria is the biggest and best.

The 300,000-acre area, named for the largest water system that drains the grasslands, lies on both sides of Interstate 17 from Sunset Point and Black Mesa north to the rim of the Verde Valley and west to Prescott Valley between State Routes 69 and 169. East of 1-17, the grasslands run to the New River Mountains.

Elevations range from 3,000 feet at the south end to 4,500 feet on the north. The land, enriched by volcanic soil, is marked by lava rock outcroppings on the hills. Washes, creeks, and networks of deep rugged canyons sustain riparian growth, especially sycamores, willows, cottonwoods, and scrub oaks.

Fenner drove her big green Forest Service truck up the four-wheel-drive road to where the "hotshot" crews waited beside the boundary fence between the Tonto and Prescott forests.

There we met Darrell Tersey, Phoenix District range conservationist for the Bureau of Land Management; Doug MacPhee, from the natural resources staff of the Prescott National Forest's Verde Ranger District; and Randy Cherington, fire-management officer for the Tonto forest's Cave Creek Ranger District. All three were dressed in the distinctive yellow "fire suits" the hotshot crews wear.

MacPhee, who started the practice of grassland burns in 1981, said the key to success is a timely rain arriving soon after a fire. The ash from the fire acts like a fertilizer, triggering a burst of tender green plants.

"After a good monsoon rain on a burn, we've seen a 270 percent increase in forb [plantlike vegetation] production," said MacPhee.

Fortunately, although range officials like to keep cows out of a burned area for at least a year, there seems little competition among pronghorn antelope, deer, and cattle.

Cows graze primarily on grass while deer browse, that is they nip off tender buds, stems, and leaves from brush such as mountain mahogany, coffee bean, and turbinella oak. Antelope both browse and graze, preferring weedlike plants to grasses. Ranchers, generally, support these fires, which the Forest Service calls "prescribed burns." But they know that fires represent a serious gamble. If the burned area cre-ates a mosaic pattern on the uplands and does not burn out a riparian area, it can be beneficial. If it doesn't, you're out of luck.

Still the growth of new vegetation in the burns, basically perennial grasses, depends almost completely on summer rains. In the high-desert grasslands of Arizona, the sumof the forage used by cattle and wildlife. "The single biggest beneficiaries of the fires are the antelope herds," said Tersey. "The range here is filling up with brush like mesquite and scrub oak. We're gettingmore and more prickly pear and catclaw, too. Historically, these brushy plants and cactuses were confined to the drainages and riparian areas. Because of climatic changes and grazing practices, these plants are spreading to the uplands and displacing the grasslands."

Antelope depend upon good visibility to see predators and their speed to run away from them, Tersey added. With the invasion of brush into the grasslands, antelope are avoiding areas they used to frequent because the cover can hide mountain lions and coyotes.

Pat Crouch, field supervisor for the Arizona Game and Fish Department, observing the prescribed burn with his assistant, Kyle Cooper, Game and Fish Department wildlife manager for Unit 21, said studiesshow that mountain lions prey on adult antelope, and coyotes kill antelope fawns.

In the last three years, Game and Fish has transplanted three supplemental antelopelope herds to the grasslands, the most recent in December of 1998. The state wildlife agency hopes that lions will not diminish this herd as severely as they did the last two reintroductions.

Cherington, the district's fire management honcho, made the decision to start the burn, and crews carrying propane torches began setting backfires. The dry vegetation burned quickly, pushed by hot, gusty winds. Most of the flames stayed in the grass, but occasionally a juniper tree erupted into a blowtorch of flame. The heat "cooked" prickly pear cactuses, and they exploded with popping noises. Soon the thick smoke drove Fenner and me to the truck, and we bounced back down the road.

"You see how fast a grass fire burns," she said. "It often doesn't stay around long enough to really kill a big mesquite or juniper. But it burns back the smaller brush like snakeweed and catclaw."

We sped away from the fire and down into the lower grasslands of Perry Mesa to look at Indian ruins.

"Most of this lower country, Perry Mesa, Black Mesa, and Joe's Hill, is former state land transferred to the BLM in a large land swap several years ago," Fenner said. "It has several large Indian ruins that have never been excavated. Some have never been named except by archaeological number."

We stopped at one of the unnamed ruins on a slope above a shallow drainage. Overgrown with grass and brush, the ruin looked as if it had 50 or more rooms. Some of the walls were exposed, indicating that a pothunter had visited the area.

"We don't have the money to maintain the ruins, much less excavate them, and neither does the BLM," Fenner lamented. "We've got hundreds of ruins like this. All we can do is patrol the area and watch out for pothunters."

We jostled down the rock-strewn road to Squaw Creek Ruin, perched on the rim of the canyon of the same name. The biggest of several ruins on Perry Mesa, this one has a rare rock wall perimeter surrounding a plaza. The ruin is extensive, and I can't even make a guess at the number of rooms.

"On the rimrock right underneath the ruin are some outstanding petroglyphs," said Fenner. She was right. We climbed down and found magnificent carvings of heavy-antlered mule deer and full-curl bighorn sheep. More than 50 rock art sites adorn Perry and adjacent Black mesa.

Two days later, I climbed a rough road up Marlow Mesa at the northern end of the grasslands with Kyle Cooper, the game ranger. We passed several old burns, but only one showed evidence of greening.

"We just haven't been getting the summer rains up here," Cooper said. "For the past two or three years, the monsoon clouds seem to split apart when they reach this area. Good rains on both sides, but not here."

He showed me a hillside covered with dry brown grass. But nearly all of it was inedible for both cows and wildlife.

"That's why it's still here," he explained. "Look, in that little patch there. I can see mostly red brome and that coarse dried-out tobosa, neither of which are considered good forage. About all they're good for is preventing soil erosion."

We saw a group of 11 antelope running from us about a thousand yards away.

Studying the herd through binoculars, Cooper announced there was only one fawn.

"A herd that size should have at least four fawns, so some predator has been hitting the young," he said. "We've got an estimated 150 to 200 antelope in Unit 21, and it is a stable herd. If we can burn out some of the brush and improve the range, the herd should do better."

Cooper said that when I-17 was built, it split the antelope population in the grasslands.

"Half is in this unit and half in Unit 19A, and the split is permanent. They used to migrate back and forth, but now they won't cross the freeway. The pavement and speeding cars scare them away," he said.

That's what is so important about the Agua Fria Grasslands Coalition, Cooper told me. "A small grassland ecosystem like this has to be kept intact, its habitat preserved and, if possible, improved for the benefit of both cattle and wildlife. Editor's Note: For more information about the Agua Fria Grasslands Coalition, contact the Prescott National Forest's Verde Ranger District, (520) 567-4121, or the Tonto National Forest's Cave Creek Ranger District, (602) 595-3300.