Only God can make a tree, but in a pinch John Lee Beatty can whip up a plausible facsimile out of mohair wool, fireproof foam rubber and steel. In fact, he has to peer around one of the bogus oaks he has planted on the stage of the Lyceum Theatre to catch the eye of the reporter who has come to interview him — a lone civilian in a space crawling with creative minions busily attending Beatty's vision of a bygone era of backyard Americana.

This is the day his set for Paul Osborn's 1939 Morning's at Seven is starting to come together, so he's running around in several directions at once. Not the best time to meet the press, but he seems to enjoy the juggling. He asks the reporter to wait a minute while he instructs workers, then the two walk offstage toward the front of the house. "I forget," he says, finally settling into an aisle seat, "what show am I to talk to you about?"

As well he should ask. At this particular point in his 27-year career in New York, the 53-year-old set designer has several worlds twirling on stages like so many plates on sticks. The day before the Morning's at Seven load-in, he did the tech for the weekend Encores! run of Golden Boy at City Center. He still has two radically different views of Chicago running from previous seasons — the razzle-dazzle of Kander & Ebb's Chicago and the nitty-gritty of David Auburn's Proof — and he only recently returned from that windy city where he did the set for Maria Arndt at Steppenwolf for director Tina Landau.

Actually, the interview is about none of the above, but about his latest brush with Alan Ayckbourn. Make that brushes, because this one comes as a twin set of two plays, which that prolific and very playful playwright has craftily (if somewhat insidiously) concocted to be performed simultaneously at adjacent theatres. True to their titles, House has an interior set, and Garden has an exterior one. Both Beatty creations, at the moment, are set up at Manhattan Theatre Club's shop in Long Island City, receiving some "detail work" before they are installed for their concurrent runs on MTC's Stages I and II.

Fourteen actors will scamper back and forth from House and Garden, under the direction of John Tillinger and the traffic direction of two production stage managers and a production supervisor. "The actors are the link," says Beatty. "They go out of the garden doors in the interior and appear in the garden, surprisingly soon, in another scene in the other play." If one play runs ahead of the other, an actor may have to vamp until they're in sync again. The inherent problems of such an interrelated exercise surfaced first on the drawing boards.

"You have to put yourself into the actor's position, but you do that normally when you're designing anyway. You do it on paper. You imagine yourself moving through the space and what it would feel like. You start from the actor anyhow in terms of scale and how you want them to stand out from the scenery. Everything is scaled to human proportions."

Aside from the significant fact that he has done all of MTC's Ayckbourn plays (Woman in Mind, A Small Family Business, Absent Friends and Comic Potential), Beatty can't imagine what qualifies him for the current assignment(s). "I think it's like an M & M binge. They started with me on Ayckbourn, and they couldn't stop. I know I'm typecast a bit as a designer for doing what other people — not me — would call realistic interiors and exteriors, and I suppose that's Ayckbourn, but I don't think of them as realistic per se."

With House and Garden, he doesn't feel like an equal-opportunity employee. "I, as a set designer, don't find them equal," he admits, "because I always find interiors sit more naturally in a theatre since the theatre in modern days is an interior space, and exteriors tend to be a little more artificial when you try to create that feeling of the outdoors."

"House and Garden" (the magazine) is doing a feature on House and Garden (the plays), and, "to my horror, they're concentrating more on the garden than the house. But the house in the script is a Georgian house. The room that the characters are in is a Victorian addition to a Georgian house. This is going to be lost on an American audience, but I have to do what the script tells me." The garden, he says, comes from designs by Edmund Luyten and Gertrude Jekyll, just as his Morning's at Seven was inspired by Grant Wood.

"When you're doing exteriors, it's easier when they're based on some artist. I looked at English watercolors to get a feeling for the foliage. You can't go to Woolworth's and buy a rack of artificial plants and stick 'em on a stage. It just doesn't work that way."

—By Harry Haun