The gift of Salinas Valley soil.

Photo by Randy Tunnell.

Photo: Fog Bank--Robert Kennedy says proximity to the ocean makes the Salinas Valley perfect.

Their names skitter off the lips and tongue or stick in the throat as if the sound of each was fashioned after its substance: the sandy Metz and Pico, the clay-rich Mocho and Chualar, the hardpan Antioch and the ancient Gloria.

The various soils of the Salinas Valley belong to two families, a very old granitic group and a younger sedimentary one. The granitic soils are descended from the weatherbeaten Santa Lucia and Gabilan ranges, now 80 million years old and still sailing imperceptibly northward from a point of origin 600 miles south. Of the particles that blow off their slopes and run down in rivulets after winter rains, the coarsest form the sandy Arroyo Seco and Tujunga. Their cousin soils, the Hanford and Chualar, have settled and weathered into finer loams with greater clay richness. In still other varieties the clay dominates, holding water to the point of muckiness and drying so hard a pick glances off them--these are the Placentia and the half-million-year-old Gloria.

All of these decomposed bits of mountain pour in great alluvial fans from the foothills, pale and dark skirts blanketing the east and west benchlands of the valley and spreading across the floor. Here and there enterprising streams carrying fresh loads of eroded granite have sliced through older deposits, leaving streaks of new dirt overlaying the old.

The other family of soils has also migrated from the south, borne along by the four-million-year-old Salinas River. The sandiest of these sedimentary types are the Metz and Pico. These mature into the silty, more fertile Mocho and Salinas, the clayey Cropley and finally the heavy Antioch soils. Their presence throughout the valley, denoted by bits of white shale from a formation south of here, marks the Salinas River''s meander through time and records its tantrums. Where the river has swung toward the Gabilans, it has left these soils, fossil-like, in odd-shaped pools across the valley floor. Where it has flooded and raged over its banks, it has deposited tracts of Metz and Pico, the first to drop out of the current after it tires. The finer silts and clays gather toward the mouth of the valley.

As the uplift of the Gabilans tilts the valley, the Salinas River edges ever closer toward the coastal range, except where the powerful Arroyo Seco tributary has built up its own sediment deposits and pushed the river back east again. On the narrow bench of land along River Road, where no such prodigious streams descend from the steep mountains, one can witness the past, and probably the future: in a global warm spell 125,000 years ago, when the riverbed was higher than it is now, the Salinas settled into a course right against the range and abruptly sheared off some of the gently sloping alluvial fans. The action left bluffs looming above the neat crop rows that stripe the floodplain today.

At that time, the mouth of the valley all the way to Salinas was swampland. The word "Salinas" itself means marsh, and the biomass and teeming microbial activity of the wetlands left the silty earth in the fabled Blanco growing area, from Highway 68 to the sea, deeply enriched with nutrients.

Since then ice ages have come and gone, floods have swollen the river''s channel and receded, and a hundred thousand seasons have done their work. What''s left today in the bottom of the five-mile-wide, 60-mile-long Salinas Valley is a patchwork of weathered alluvial and sedimentary soils suspended over two aquifers, one 180 feet down, the other 200 feet below that--a masterpiece of natural engineering.

Of the 20,000 soils in the United States that scientists have rubbed between their fingers, smelled, squinted at and classified, these soils are among the most valuable. Bumper crops of food and dollars spring from them two, sometimes three times a year.

But here, the fight that was long ago lost in the crowded Santa Clara and San Fernando valleys, once carpeted in orchards and row crops, is in full swing. After eons of tectonics and millennia of erosion, the soil of the Salinas Valley is losing ground.

Terry Cook counts himself among the valley''s biggest fans. A soil scientist for 40 years, Cook led the team of 10 scientists who mapped the soils of Monterey County''s two million acres between 1963 and 1970, traveling by horseback, helicopter and hiking boot to reach the places trucks couldn''t go. The result of this labor is a tome the size of a telephone book which is still the definitive record of soil types for the county.

"In the world," says Cook, "I''ve been along the Nile River, and those Nile deposits are no better than these Salinas soils. Salinas is number one."

At 67, Cook has retired from the Natural Resources Conservation Service into a consulting gig that affords him copious amounts of time behind the wheel of a new double-cab pickup. Rail-thin, with lively brown eyes that light up regularly, Cook is hard pressed to contain his enthusiasm about soil. He talks nonstop, pointing out paved-over alluvial terraces inside the Salinas city limits from memory and steering with one hand while he flips through the soil survey with the other to confirm that the Salinas Auto Mall was indeed built on Class I Chualar soil: prime farmland.

"This is so amazing to me," he declares as he navigates the truck onto Espinosa Road just north of Salinas. Across Highway 101, rolling hills under strawberry cultivation mark the site of the future Rancho San Juan housing development. "You are south of Prunedale and it''s like, ta da! 2001! Jeez, here''s this beautiful valley and it''s just gone--well, not gone, but in trouble."

Trouble has arrived from the north. The Bay Area is bursting with four million people who must live somewhere, and the pipeline of Highway 101 feeds them directly into the Salinas Valley, where two cities and a string of towns dot an otherwise sheer expanse of flat ground. Trouble comes also from within the valley itself, where families overflow out of small houses and cramped apartments. Those whose business it is to build houses look at the serene acres of farmland and see frames, roofs, roads materializing on them--usually the large frames, tile roofs and wide roads of suburbia.

"I don''t know where to put development," Cook says, "but it seems to me society ought to pay to keep prime land in agriculture."

On Espinosa Road he pulls over next to a field of iceberg lettuce, hops out of the truck and picks up a clump of Chualar soil.

"Work this in your hand," he says, squirting it with a water bottle. "In the old days we used to use spit."

It immediately forms a ball and gets sticky. As geologist John Tinsley later explains, that''s due to its clay content. "In general," Tinsley says, "20 to 25 percent clay is good. It has good cationic exchange"--that means it efficiently conducts nutrients to plants--"and it holds water.

"Chualar is like this. Too much clay and soil is too heavy; not enough clay and it''s too dry. Not enough mineral content--it has nothing to give. It''s inert."

Cook likewise praises the Chualar. "These aren''t the richest soils of the valley, but they''re still one of the most valuable soils," he says.

Chualar needs defending. It''s one of the principal soils of the region north of Salinas, which has been slated for growth in deference to the revered Blanco growing region.

Last week the Salinas City Council approved a general plan proposing that 4,000 acres of ag land adjacent to the city be converted to urban use, mostly for housing. In accordance with a 16-year-old policy of shielding the Blanco area south and west of town, the vast majority of those acres lie north and east of Salinas on the Gabilan alluvial terraces. Though a map in the general plan identifies most of the ag land slated for development as prime, the text notes that "the City has selectively focused future growth away from the most important agricultural lands surrounding Salinas."

That kind of talk gets Robert Kennedy''s goat. Kennedy is also a champion of Chualar--and every other productive soil in the valley. He has no patience for distinctions between "important" and "most important" farmland. If it''s producing a crop, he figures, then it works and it must be protected.

Kennedy, a tall 70-year-old who punctuates his arguments with harmless oaths ("Balderdash!" being a favorite), is the son of a Kansas farmer. He decided to forego the family business when he returned from the Korean War and instead became a professor of agriculture. He taught at Hartnell College for 26 years, picking up a degree in meteorology from the Naval Postgraduate School along the way.

Kennedy spreads an arsenal of maps, graphs and manifestos across his dining room table, most emblazoned with capital letters and exclamation points for the benefit of elected officials who have received his impassioned testimonials. Kennedy''s goal is the same as that of other preservationists, but his means are different. If his campaign had a slogan, it would be "It''s The Weather, Stupid!"

He waves a chart. "The reason we have this productive agricultural area here has nothing to do with soils and everything to do with climate."

The key, he says, is the ocean. Fifty-nine degrees on average all year, it creates an envelope of cool air 700 to 1,000 feet high and blows a cooling breeze over the valley every afternoon. Combined, he says, ceiling and breeze protect the cool-weather vegetables (lettuce, broccoli and all the other ingredients of the World''s Salad Bowl) from the heat and extend the growing season throughout summer, allowing for two and often three crops per year--a clear improvement over the short spring and fall growing seasons in the hotter Central and Imperial valleys.

In some respects Kennedy''s argument arises from distrust. He contends that overreliance on the official soil classification system, which detracts points for slope and for shallow soil, lets developers manipulate data in order to make the case for building on presumably poorer land--without taking into consideration the land''s actual capability. To make his point, Kennedy invokes the case of the valley''s highest dollar-per-acre crop where it flourishes on rolling hills in allegedly inferior soil.

"There are lots of strawberry fields between Prunedale and Castroville on Highway 156," he says. "Now that''s $40,000 an acre. That''s Class 7 soil. That''ll prove it''s not the soil. It''s the climate."

But of course, without the soil to put plants in it doesn''t matter how good the climate is for growing vegetables. And for that reason, Kennedy says emphatically, Monterey County farmland is a "green gold mine." In exchange for billions of dollars pumped through the local economy, the public pays almost nothing.

"We don''t have to hardly do a thing," he chuckles with delight. "Just keep the roads up so the farmers can keep the wealth coming in! And the beauty of it is no one can take it away because you can''t change the climate. The only way we can destroy this industry is if we do it. And we do it by building houses on it."

If Monterey County were a state, its revenue from vegetable production would exceed that of every other state in the union except California.

That is not a pond of small fish. California''s $30 billion agricultural economy makes it the most productive in the world, according to Monterey County Agricultural Commissioner Eric Lauritzen. And within this staggeringly productive state, the Salinas Valley is a star. Its 225,000 irrigated acres of farmland--representing 2.6 percent of the farmland in California--produce 34 percent of the state''s vegetable crops. Forty-three of its crops gross over $1 million apiece annually; seven of those rake in over $100 million each, with head and leaf lettuce totalling about $600 million. The valley grows some 90 percent of the nation''s summer supply of lettuce and exports nearly a billion pounds of produce to the rest of the world. Farmers reap average gross revenues in excess of $12,000 per acre; wheat, by comparison, yields an average of $112 per acre.

Without the valley''s contribution, the nation''s grocery stores would be considerably emptier--or, more likely, stocked with travel-weary produce from Latin America and overseas. Monterey County grows just under half of the country''s broccoli, cauliflower, lettuce and strawberries, over half its spinach and 85 percent of its artichokes.

The sheer numbers are astounding, but Monterey County''s agriculture industry rests on more than the pillar of brute tonnage. It balances across the stability provided by more than 60 crops.

"We''ve got 1,200 acres of citrus. We even have avocados," says Lauritzen. "There just aren''t that many places in the world where you can grow this many crops with such a long season."

Lauritzen came here from his post as agricultural commissioner for Sonoma County, where wine grapes make up more than half the agricultural output. "Monoculture puts you at the mercy of market trends," he says. "Here the industry is very responsive to the consumer. They can grow different things in the same soil. That adds to the strength of the industry as a whole."

It even, he notes, stabilizes the labor force. After the fall lettuce is picked, it''s time to prune grapes. The laborers keep making money, and as long as they''re here, they continue to spend, bolstering the rest of the county''s economy.

That dynamic--the flow of money through the hands of the laborers and support personnel who work in the fields, packing houses, coolers and shipping warehouses--is the bigger story behind the local ag industry.

Steve Nukes''s San Luis Obispo consulting firm has been preparing Monterey County''s economic forecast for nine years. When he estimates the impact of agriculture on the county as a whole, he starts with the gross value of produce "fresh on board"-- out of the fields and onto trucks--and applies a multiplier.

"As that three billion dollars filters through the economy in terms of wages and other things," he says, "those are spent in the economy. Goods and supplies are bought, and those provide wages and jobs for people, and those in turn provide wages and jobs for other people... so you can figure that three billion is probably worth six to eight or possibly even nine billion in terms of overall economic activity. Agriculture has a very high direct local impact."

Or, as shipper Dennis Donohue puts it, "In the Salinas Valley, agriculture is the straw that stirs the drink. Without it the copiers don''t get bought, the cars don''t get sold--none of this happens.".

The three keys to making money in agriculture are location, location and location --or so they like to say. Policymakers, farming specialists, even the very market itself bow to the Salinas Valley, its climate and its soils. But they seem to look upon the rich, silty, river-deposited soils of the Blanco region with awe, and to look at other growing regions with something less than awe.

"In the Blanco those are very good, dark, rich soils, the Salinas clay loams out there," says Richard Smith, an Agricultural Extension soil specialist. "They''re typically very deep, very rich, very fertile and very good to work with for growers. They''re highly productive.

"Along the river you have more silt loams, like the Mocho and Pico series," he continues, "and they are very good, too--maybe slightly less fertile, but that can be managed.

"Then when you move to the east side of the valley you get into the decomposed granite soils. Those tend to be more coarse, the Chualar sandy loams. They are challenging for growers to work with because they are less fertile. Things tend to leach out of them, they tend to get hard. It''s hard to keep the fertility levels up where the roots are."

In general, Smith praises the granitic soils anyway--they''re just not superstars. And the land prices reflect that belief. Leased Blanco land commands as much as $2,500 per acre each year, as opposed to $800 an acre and up in other areas. Proven Blanco cropland has sold for as much as $37,000 an acre. The average sale price for farmland in the county is $20,000.

Of course, everything''s relative in a market economy, Dennis Donohue says. If the market is doing poorly, the higher yield from Blanco acreage isn''t much of a consolation. And, he points out, the packaged salad business has changed the valley''s economics. A bag of salad is not going to vary wildly in cost to the consumer the way lettuce did last spring, so growers must find other ways to increase profit.

"Because it''s one fixed price, what everyone''s trying to do is control cost with cheaper rents and improved yields," he says. "So we start to see a movement. People are saying, ''Maybe that''s not such a bad idea to grow in the Old Stage Area.''" The Old Stage Area is on the southeast side of Salinas, perched on top of, yes, granitic alluvial fans.

Stan Corda nurses no such prejudices. In 1951 Corda started farming land on River Road that his father bought in 1918, when only five families lived in the neighborhood. For "eight or 10 years" he leased 200 acres on the Santa Lucia side of the road on an 875-acre terrace where the current owners have petitioned to build 375 houses, a wine tasting room and a golf course.

"They''re calling it marginal land, but in my opinion it''s not marginal," he says. "I grew onions, broccoli, strawberries, seed crops, lettuce. They all did real well."

According to the soil survey map, all but one swath of the parcel is slightly sloped granitic soil from the mountain range: Placentia, Arroyo Seco, Gloria, Chualar--almost all Class II and III soils. Despite its designation, Corda recalls that it didn''t need much help pushing up healthy crops.

"I didn''t have to add iron because it was already on the acid side," he remembers. "It was low in phosphate, potash--I had to broadcast that. And I think maybe it was deficient in boron. It takes very little boron."

Corda, who is now retired from farming and leases out his own land, has been a vocal critic of the development plan all along. "If this land is sold for development, look at the people who are out of work," he says. "My nephews are farming it organic, and that takes a few years to certify, so that''ll all be lost too. Plus we''re growing food for people to eat. There''s just so much farmland and once it''s covered up, it''s lost forever."

The county is in the final stages of working out its General Plan, often referred to as a blueprint for growth for the next 20 years. The first draft, compiled by county staffers, proposed converting a modest 3,000 acres of agricultural land into urban use between now and 2022.

On reading the draft, a number of landowners, including Corda''s neighbors, panicked and rushed to get their property rezoned for development. If all were approved--and some have already been denied--they would have added 1,000 acres to that sum. The supervisors heard requests last week and are hearing more this week. At press time they had not made a decision on the property across from Corda.

Some of the cities have different ideas as well. Salinas intends to grow by 4,000 acres over the next 20 years. Tiny but ambitious Greenfield envisions itself expanding by 5,000 acres. All told, the cities'' wish lists call for 11,000 acres of ag land to be converted over the next two decades. That''s $132 million worth of revenue subtracted from the local economy''s bottom line--almost $400 million, with Nukes'' multiplier. And it''s another blow to an agricultural land base that has lost 5,500 irrigated acres to urban use in the last 18 years.

Stephen Griffin started working for his father''s company, Misionero Vegetables, in 1978. Today the Griffins till some 14,000 acres, about half of them organic, in the Salinas Valley and Yuma. Eight hundred of them are on Espinosa Road, not far from where Terry Cook bounded out of the pickup to give a short lesson on the properties of Chualar soil. Driving north on Highway 101 to get there, Griffin ruminates on the costs of paving ag land.

"When I was growing up there wasn''t anything out here," he says as Northridge Mall slips by. "Pretty soon they''re going to pave over all the ground. I don''t want to knock the auto dealerships, but this was good ground. It''s kind of odd no one raised the issue of prime ground when that went in."

On his farm, Griffin points out various crops: iceberg, broccoli, strawberries. In a small valley hidden from the road, organic romaine, frisee and iceberg grow like green blossoms in black soil. Griffin points across the narrow valley to the sudden smattering of new white houses on the hillside.

"The competition is out there," he says. "That one just went in, and that one''s new. When houses go in it''s tough. We turn on our pumps and they say it''s too noisy."

The truck creeps along the dirt road and winds up the hill, past the hunched figures of workers picking strawberries.

"Backbreaking work," Griffin murmurs. "It''s the hardest crop of all. We''ve tried different ways--they were developing a platform so people could lie down --but there''s just no other way to do it."

At the top of the hill Griffin idles the truck and looks across the valley. Not far to the left, across 101, the midday sun refracts off sprinklers watering dark unplanted hills. "There''s Rancho San Juan." He points ahead. "You can''t see it now, but right across there is Las Palmas. That was a big one."

He''s quiet a minute. "We haven''t done a good job of stopping sprawl. It''s everywhere."

And so it is. All along the coast, civilization is spilling over the edges of its basins, seeping outward like stains on the landscape. In some places it spreads over swamp, valley, grassland, up the feet of mountains. But here it is advancing over tilled fields, and in so doing it drowns the very thing that makes civilization possible.

Without cultivation to ensure a steady supply of food, humans never would have stopped migrating, never could have built cities, made wars, written books, invented engines, crafted semiconductors.

But agricultural land is in a fragile state. It took 80 million years of geologic activity to produce the Salinas Valley''s edenic conditions for growing food, but those could be rendered null in a few decades. In a scant 40 years the flowering fruit trees of the Santa Clara Valley gave way to summer smog and a tide of suburban forces so powerful it crashed the floodgates all the way to the Central Valley and has now turned south toward Monterey County. If the same thing happens here, some other place with less exceptional soil and climate will step up to grow the food the Salinas Valley no longer can.

Civilization will not be derailed just because artichokes must be imported from Italy. But Monterey County will have traded away the one sure thing that humans will always need and bet the farm on a future as suburb, where the only hint of the region''s past wealth and its blessed combination of ground and sky will be backyard gardens that, every spring, summer and fall, do surprisingly well.