The Boston Landmarks Orchestra presents free classical concerts in significant locations around town, often focusing on works with special appeal to children. On Wednesday evening, at the Hatch Shell, a crowd of all ages filled the oval lawn in a sprawl of blankets, folding chairs, and picnic baskets for the orchestra's "Green Masterpieces: Air and Water," a concert of pieces inspired by nature; the concert will repeat Sunday at Jamaica Pond.
Rossini's "Overture to the Thieving Magpie" opened the evening. The orchestra's crisp playing and nuanced dynamics, under the lively baton of Charles Ansbacher, sharply etched the piece, from strutting march to tip-toeing waltz to big finish. Almost from the first note, a flock of preschoolers danced their appreciation at the foot of the stage.
Next, though the sun still illuminated the cloudless sky, came two Debussy Nocturnes: "Nuages" and "Fêtes." For the first, the orchestra conjured the clouds missing from the scene. Debussy's wispy sonorities let the traffic noise through, but the orchestra's compelling playing still cast its spell over the audience. The whimsical procession of the second piece was superbly animated by the orchestra, and had the little dancers return to their pirouettes.
The first half ended with Bedrich Smetana's "The Moldau," which seemed at times a touch muddier than the composer intended. Still, during the intermission an older gentleman could be heard whistling the flowing main theme.
The second half opened with the menuetto from Leopold Mozart's "Cassation in G (Toy Symphony)," which featured nightingale, cuckoo, and quail cries punctuating its clockwork cadences.
Next, a world premiere, 19-year-old composer Stephen Feigenbaum's "Speak, Sing, Whale," a Landmarks Orchestra commission that incorporated tapes of whale vocalizations. Drawing from both chugging Steve Reich minimalism and Igor Stravinsky chord stabs, Feigenbaum nicely varied his approach, with the whale sounds sometimes submerged within the orchestra and at others breaking the surface for a solo.
A suite derived from Handel's "Water Music" closed the program. The bold antiphonal and contrapuntal textures of the movements were literally written for the river setting. The sun had fully set by now, but the orchestra's lustrous performance provided its own glow. The dancers were ecstatic.
As an encore, the orchestra played a bravura version of Johann Strauss's raucous "Thunder and Lightning Polka," following it with Leroy Anderson's exuberantly goofy "Fiddle Faddle," part of Landmarks' summer-long tribute to the Cantabrigian composer's centennial.