Folks keep inviting Ed Zern on chance-of-a-lifetime outdoors adventures and he keeps going, even though at age 75 he rarely writes about his exploits any more and his monthly "Exit Laughing" columns are humor essays containing, as he puts it, "no useful information."

He's probably too old to do the things he does, flying off to Scotland and Labrador, Kenya and Montana and plunging into the field to fish and hunt with youngsters.

But the gray-bearded Zern is an institution. Dig he must. Maybe because he keeps plugging away, his funny columns still seem like fresh air in a stuffy room full of hook 'em and shoot 'em prose.

Zern approaches "Exit Laughing," which appears on the back page of Field and Stream every month, with the same youthful zeal that induced him a few years ago, at 72, to crawl along a cold, Scottish creek on his belly in pursuit of a stag.

"I panic every month," he said, "convinced I'll never have another funny idea."

Odd he should worry. With one brief exception, Zern has been writing "Exit Laughing" every month for 28 years, and August's offering is as amusing as any.

Only once, during 1975, did Zern have to beg off writing and ask his editors to reprint some gems from the past, and that was so he could nurse his wife through lung cancer, which took her life.

A mean-spirited reader wrote to protest the reruns, and Zern wrote back, "I just heard the New York Philharmonic play Schubert, and I learned later they'd played that same piece two or three times before. It still sounded good."

It was Zern's wife who convinced him to take up outdoor writing in the first place, he said, after he complained of dreary writing in magazines of the 1930s.

Almost 30 years later she convinced him to quit the hectic pace of Madison Avenue advertising work and take up fishing and hunting and writing about them full time. Nice suggestion. Nice wife.

"We were in Europe," Zern said as he settled his hands around a glass of Scotch in his dark living room, "and we had to rush to catch a flight to New York so I could get back to work."

But they stopped in a little Spanish coastal town, Almunecar. A hotel there looked nice. They took the bridal suite -- four rooms overlooking the Mediterranean -- and wound up staying.

The third or fourth day, Zern said, "My wife told me she had figured out we could keep living in the bridal suite indefinitely, eating fresh seafood from the market, and it would cost us less than we were paying for school taxes in Scarsdale."

Zern said he went home with the intention of quitting advertising and selling the house, but never managed the latter. "I couldn't find any place to keep all my decoys and trophies and African sculptures."

So these days, when he isn't flying off to some exotic land to hunt caribou or fish for salmon, Zern rustles around alone in the cluttered old slate-roof homestead, hard by the Bronx River Parkway, and looks for ways to avoid doing his column.

"He has a terrible travail in writing and he's a chronic last-minute type," said his editor, David Petzal. "He's the kind who gives editors heart failure."

Zern gets special treatment because whatever he turns in is bulletproof, Petzal said, and he always produces, even if it is late.

"We permit Ed certain levities. He's into Joycean, run-on sentences now. Anyone else, we'd chop.

"But we leave Ed alone, because he's a unique stylist who knows what he's doing and because if we don't, he yells, screams and throws things."

What's nice about Zern's columns is that although they usually don't amount to more than a good chuckle, they carry with them the language and baggage of a lifetime spent hanging around guns, dogs, fishing gear and promising water, plus a willingness to laugh at himself.

Thus when he invents a yarn about the latest meeting of the Madison Avenue Rod, Gun, Bloody Mary & Labrador Retriever Benevolent Association, glimmers of truth shine amid the nuggets of mirth.

Sometimes the glimmers are too much like truth, such as the time Zern wrote that his outdoor writing colleague Ted Trueblood was an invention of the editors of Field and Stream, who picked out a nom de plume so preposterous they expected readers to recognize it immediately as a hoax.

Of course there really was a Ted Trueblood, who was mightily offended when everyone believed Zern. It took a while to sort all that out.

Zern recounted some more highlights of his career as the evening wore on. We probably could have talked until the Scotch ran out, which would have been a while, but his column was three days overdue and he had to pack for Alaska.