A strange, long, but unfortunately unhypnotic novel by Lenz (The German Lesson, 1972; The Heritage, 1981, etc.) that follows the life of a dullish, somewhat retarded boy named Bruno into manhood on a remarkable tree nursery near Schleswig. The nursery is owned by a man named Zeller, called by Bruno simply ``the chief,'' who reclaimed the barren land from its former use as a military training ground and made it into a lush and fecund natural paradise. The town has never sanctioned the Zellers' presence, for all their success: the Zellers were refugees from East Germany (and Bruno their ward ever since the boat he and his parents and the Zellers were on sunk), and their foreignness is a barrier, as are the chief's utterly consistent moral scruples. When the chief approaches his death, he deeds over much of the nursery to Bruno- -and frantic, gross attempts inside the family and the town to circumvent the legacy provide what little plot there is here. A Dostoevskyian section near story's end about the bad conscience of a local man--``the shiverer''--sharpens the air of allegory that the novel already largely presaged: the idiot, the garden, war, etc. Still, at least in translation, this is a slow, textureless book--about as narratively exciting as watching one of Zeller's conifers grow.