The Garden basked quietly in the last days of a mild, dry December, walled by the buildings that keep it largely hidden from the noise and traffic beyond. But then, barely days into the new year, it was transformed overnight into another world, one of dazzling white where a Himalayan Cedar becomes a glorious frozen firework. Snowfalls this heavy are not common in our area, however, and may come years apart. The Tawes Garden in Winter is normally a landscape of muted grays and browns and mossy greens, but not lacking in interest if you look: The criss-crossing trunks of a sinewy American Hornbeam and a rough-barked River Birch form a study in contrasts, while the dark-needled bulk of twin Pines anchor a bright winter sky firmly to the ground. A "Waffle Rock", almost invisible in summer shade, now reveals the strangely geometric patterns that human brains find so hard to accept as natural, no matter what the geologists may say. And by late February Carnelian Cherry is popping open a bright yellow canopy, while toward the end of March, snow of another type is mounded lavishly on the branches of a Star Magnolia.