You often wonder what New York will look like when the last corporation has moved away and the island is once more covered with grass; and the answer is, it will look just fine.

The sun was setting when I made the pilgrimage last weekend to see an acre and a half of wheat at the base of the town's biggest towers, the World Trade Center. All that part down there, called Battery City, is filled land, sand and rubble, and soon it will flower with office buildings and similar stuff, but at the moment it is a wheat field, and there (like Ruth in tears amid the alien corn) was Agnes Denes, her hair red as the sunset:

"Had to fight every inch of the way to get this land for the growing season," she said. "They kept putting me off and moving me down the island until here there isn't any farther place to move."

Denes (pronounced Dennis) is a conceptual artist who gave up painting pictures 15 years ago and has turned to more cosmic approaches to art, such as burying haikus, chaining trees and hunting about for intelligible explanations of what she's doing.

Here at the southern end of Manhattan, she sought a contrast and, God knows, found it.

"After 300 years of the buildings intruding on the fields, the fields are intruding on the buildings," she said. She managed a $10,000 grant from Public Art Fund, a private foundation endowed by a lover of civic art, and which goes in for things like murals on warehouse walls.

Many truckloads of topsoil were hauled and spread two inches deep. The land was so poor that not even weeds seem to grow on it, and the winds from the west are ferocious. "There were wheat fields here in the 17th century," Denes said, "but more to the east, and at Murray Hill.

"We dug the 235 furrows by hand she and volunteers and a few paid laborers and planted the hard red wheat last May. It took forever, hundreds and hundreds of hours."

"Woman-hours," said a gallant man giving credit where credit is due.

"Man-hours," she said, confessing men did most of the work. (Ha).

But back to the lofty plane. "The idea of a wheat field is quite simple," she said. "What creation and life is all about. But we tend to forget the basic processes."

Farmers don't. Of course they have better land and either get better yields than Denes or else go broke and move to New York, the great haven for folk who wonder what the hell to do now.

Denes planted six bushels and estimated the harvest at 40, not quite up to the biblical hundred-fold, but then this is a naughty world. In the event, she harvested 10 bushels on Saturday. American Cyanamid, a corporation differing from the gleaners of the Old Testament grainfields, but an outfit whose heart is clearly in the right place in this project, provided a combine for the harvest.

"I didn't want anybody to get hurt," said Denes, when asked why the sheaves were not brought in by hand, and come to think of it, a bunch of New Yorkers swinging sharp scythes would probably not pass any safety laws.

Denes marched, virtually danced, behind the little combine on Saturday, and that bending figure over yonder was Bob Frankel, a city boy, who with a few others was harvesting a bit by hand. He will be able to say to his great-grandson:

"Eh, back in '82 when I was young I harvested wheat by hand right here in south Manhattan. The world is different now." And the lad can dream back to the simple uncomplicated olden times of 1982 when a man got an honest sweat from honest labor in New York.

"There were going to be several hundred people here to help us celebrate," Denes said, but it rained cats and dogs Thursday so that was off. Friday was, however, rarely glorious, the sky cornflower blue without clouds and the sun distinctly Egyptian in its benign strength. A steady breeze (the wind that bothers the wheat as it grows) ruffled the hair and open collars of the handful who showed up for the eve of the harvest. One fellow poured a small libation of club soda on the field. It was merry and solemn at once. A numinous air prevailed. One felt one should sacrifice an editor, as the ancients sacrificed beloved creatures for fruitful fields, but none was near; only a couple of writers and cameramen trailing their usual umbilicals of cable.

Bob Newman, a Washington artist who moved to New York because that's where it's at, regarded the slanting light with approving eye and deplored the art scene of Washington. So little support to artists. Things go better on the Hudson. Streets are safer up there, too, he thinks.

Denes had done a lot of thinking before she even started the field, and is thinking now what to do with the grain--maybe send it to Cambodia, or make bread with it for the Manhattan poor, or maybe sell it to the highest bidder at the stock exchange. At least she thought it up, made it grow and got it harvested:

"Manhattan is probably the richest, most congested, most professional and fascinating island in the world. To grow wheat on it, seemingly such a waste of precious space, can create a powerful paradox. Or an anxious calling to account.

"To go against the grain, do the impossible, grow the wheat field on this island, can call our attention to priorities. To realize that unless human values are reassessed--even life may be in danger. The field can represent all that this land stood for and I hope still does."

The light faded, the few humans began to leave. The wheat at the edge reached only to mid-calf, but sheltered in the center of the field it was waist-high.

"The wonderful thing," said Newman, "is the way the bugs appeared. Little spiders specially adapted for catching other bugs on wheat. Where do they come from? How does the first bug even know -- why would he think -- there is going to be any wheat for him to pester?"

Optimism. It's why there is a New York.