Most North County farmers have small farms, and they can't afford to absorb much theft.

The light in old avocado groves is dim, and when you look up, the highest leaves meet like interlocking panes of green glass. Branches and trunks form Gothic arches, a few limbs stretch out like pews, and the groves are as still as churches.

But when the price of avocados rises to more than a dollar a pound, North County groves can turn from empty churches into dangerous frontier towns. Growers load their guns. Thieves cut locks, scale fences, or simply whirl the dial of a combination lock. They work in groups or by themselves, in the early morning or midday, on weekdays or weekends, when the owner is absent and when he's at home 20 acres away. They haul avocados in Buicks, pickups, pillowcases, and duffel bags. Sometimes they wait until the fruit has been picked and steal it from the bins. The more professional they look, the more innocent they seem.

"Let's say two pickup trucks pull up to a grove," says Howard Seelye, spokesman for the California Avocado Commission. "And four or five or six people get out of those trucks and have picking poles and ladders and bags and go to work quickly in a grove."

What's a passerby going to think? he asks. An illicit crew looks just like a hired one unless you're the owner of those trees. And the problem of identification only increases when purloined fruit leaves the grove.

"It's not like they have serial numbers," says Lieutenant Dave Herbert of the Fallbrook Sheriff's substation. "How do you tell a stolen avocado from a regular one?"

Packing houses and restaurants are supposed to demand proof of ownership, but small thefts (hundreds rather than thousands of pounds) are sold to restaurants, and larger amounts are probably sold to packing houses under false documents. Until the avocado commission thinks of a safe way to brand each piece of fruit, the only way to prove you've been robbed is to catch the thief in flagrante delicto, as Jeanne Strand, aged 74, did last July.

Strand is an elegant woman. She looks as though she could play bridge with your mother-in-law, run the music society, or anything else that refined women in Fallbrook do after the age of 60 except, perhaps, what Strand did do on July 1, which was to order a thief to put back her avocados and enforce the order with her husband's .38 Special.

Strand and her husband Lyle own a 22-acre grove in Fallbrook, where they've lost about $100,000 worth of avocados to thieves in the last ten years. On July 1, when avocados were worth $1.50 a pound, the Strands' avocados had been picked and were waiting for transport to the packing house. Lyle was out of town, so Jeanne walked down to check on the bins. She took Lyle's gun with her because the fruit had been stolen out of the bins before.

When she reached the bins, she found a man loading the last of what she estimated to be 500 pounds of avocados into the back seat and trunk of his Buick. Although Jeanne was holding the gun, the man ignored her demands to stop, and he jumped in the driver's seat.

"I've never seen anyone move so fast," Jeanne says. "I never would have caught him if the battery hadn't been dead."

Despite the revolver, the man got out and tried to push the car. It wasn't until Jeanne fired a shot in the air that he stopped, got out of the car, and put the avocados back into the bin.

Jeanne told him to stay put until the police arrived, but the man's friend arrived in a pickup, in which the two drove away. They left behind the Buick, which was registered to Francisco Gonzalez, whom Jeanne then picked out of a photo line-up. Mr. Gonzalez pled guilty to grand theft avocado in late October.

Arrests are rare in avocado theft, but another one occurred in Fallbrook just a few days after Jeanne Strand fired a shot in the air. On a street called Paso de Oro Verde, or the Road to Green Gold, an employee of the Bejoca grove service found a man named Edward D. Allan picking avocados in a 32-acre grove. According to Bejoca, Allan asked if he could have or buy the dozen or so he'd already picked. The worker, whom I'll call Frank Salazar, refused, and Allan left.

A few days passed, and Frank Salazar went back to the same grove and found Allan hooking more avocados out of trees. By this time, Salazar had been advised that if he saw a trespasser, he should hide and call the office. Salazar took down the license plate of a truck with a bed nearly full of avocados and called the number in to Kathryn Wolk, who owns Bejoca with her husband, Charley. Kathryn quickly relayed the information to the police, but sometimes it's as hard to find a grove in peril as it is to find a stolen Hass.

"[Salazar] has quite an accent," Kathryn says, "so I misunderstood one of the numbers and thought he was saying a letter." The sheriff's department said the format was wrong for California plates, and they asked for the nearest cross street to Paso de Oro Verde. Kathryn tried to explain that cross streets don't help much in rural Fallbrook, but they insisted, and when she finally reached her husband on the radio and passed on a street name, it was the wrong street, and the police wound up outside the locked gate of the wrong grove.

The very next day, July 8, Edward Allan returned to the Bejoca grove for the third time. This time, deputies found the grove and arrested him with 181 pounds of avocados, enough to make the crime a felony. He pled guilty and was sentenced to 180 days of confinement and three years of probation. During those three years, Allan can't enter any San Diego County grove without proof of employment, a stipulation added because Allan is, he told the judge, a grove manager by trade. Three days after Allan's arrest, thieves stripped 4000 pounds of avocados from the trees of a 20-acre grove while the owners and their neighbors were home. No arrest has been made in that case.

Since neither the sheriff's department nor the avocado commission keeps exact figures on avocado thefts, it's hard to know how many cases are prosecuted and how many are never solved. In 1996, the farm bureau estimated that between $2 million and $10 million worth of avocados are stolen each year. Since 1990, when the commission began offering rewards to witnesses, 72 people have been arrested for theft -- 40 of them for grand theft (a value of more than $100). Only 40,000 pounds of stolen fruit have been recovered in that time, while "most of it," says spokesman Howard Seelye, "disappeared."

Some arrests and convictions are for small amounts -- a mere 22 pounds of stolen avocados sent Mark Fountain to prison last July. The fruit was worth just $13 on that particular day (he stole them in February), but Fountain had already been to prison twice and was on parole when he committed the crime.

Other thefts are more substantial. The largest reward the avocado commission has ever paid went to a Temecula woman who identified 12 members of a theft ring in north San Diego and south Riverside counties. She received $5000, which may have seemed like small compensation given the consequences to her. "There would have been reprisals," Seelye says, "but the woman moved. She had to move because they knew who she was."

Charley Wolk of Bejoca has also experienced professional theft, though of a more cinematic kind. "A couple of years ago," he says, "we had a hijacking of a packing-house boom truck." (A boom truck uses a crane to lift 1000-pound bins of avocados onto its bed.) Wolk describes the hijacking as a "classic Bonnie-and-Clyde" hoax in which a woman stopped at the side of the road and pretended to have car trouble. The driver of the avocado truck pulled over to help, and a man came out of the trees with a weapon. "[The police] never caught them," Wolk says. "They found the truck down in San Ysidro with the fruit gone."

Protection for San Diego County growers is increasing, but agricultural crimes are hard to prosecute. In Ventura County, where investigators have been swamped with thefts of aluminum irrigation pipe, growers are encouraged to mark all equipment with a ten-digit FBI code called an owner-applied number. The number, says Eric Nelson, a detective with Ventura's rural crime division, helps officers both to trace stolen equipment and stop crimes in progress. When the number is posted on a sign outside the farm or grove, for instance, deputies on patrol can track down the owner and ask whether a person or group of people is authorized to be there. And since the numbers are stored in a database with mapping coordinates, "we can dispatch a helicopter directly to that property," he says. The mapping coordinates are useful where addresses and cross streets are few -- a tool that would have been helpful in the Edward Allan case.

Or maybe not. An owner-applied number would assist local officers, says Elisabeth Silva, agricultural crimes prosecutor for north San Diego County, only if the computer system were more efficient. Silva believes the ten-digit ID number is a good idea, but "at the moment," she says, "there just doesn't seem to be enough space in the statewide law enforcement computers to enter in the numbers and be able to call them back." Until the legislature approves a budget for expanding the computer system, Silva says, the process will be too slow.

But North County farmers are happy to have a new district attorney -- Elisabeth Silva -- who concentrates solely on agriculture. Silva volunteered for the post last March and went to rural crime school -- the only one of its kind in the country -- near Monterey. There she studied cattle, horse and tack, equipment, and pesticide theft, plus ritual animal slaughter by Satanists. So far, there's been more avocado theft than ritual slaughter.

"Agriculture," Silva says, "is a $4 billion economy in San Diego County," making it the fourth largest industry. Most North County farmers, she says, have small farms, and they can't afford to absorb much theft.

As for Jeanne Strand, who was at the Vista County Courthouse with her husband on October 29 when Mr. Gonzalez pled guilty, she's happy to have caught someone after all these years of losses. "I found I could do something," she says. "Lyle's always been there in the past." She hopes the arrest will intimidate local thieves, but she won't go on patrol again next year because she and Lyle are selling the ranch. "We're getting a little old to run up and down those hills," she says.

Those who are staying on in their groves, though, plan to defend their fruit in the manner of the old west. "If you're on my property," says the woman who lost 4000 pounds last July, "you may get a shotgun in your face. I'm not," she warns, "a little woman."