An illustrator who made a fine debut with his oil paintings for Weller's Riptide (1990) turns to watercolor for his own story about an artist on a woodland expedition with his son. (New Jerseyans may recognize the Delaware Water Gap area.) Dad is looking for ``oak trees, shadows, rocks, and water''; the boy, a budding naturalist, hopes for ``a unicorn beetle...and a green cricket frog.'' Along the way, the search occasions some amiable negotiation plus splendidly evocative double spreads (Blake seems to have found a number of ``perfect spots for his paintings); at last, after both fall into the stream and decide it's a laughing matter (which several deer pause to observe), Dad settles down to paint. The interplay between parent and child, each dedicated to his own valuable pursuit, is as appealing as the lovely play of light through trees and water. (Picture book. 4-9)