The School of Music at the University of Southern Maine runs a handful of youth ensembles, both orchestral and choral, for middle school and high school students, conducted mostly by members of the university’s faculty. Twice a year, in the spring and fall, these ensembles give public performances, and on Thursday, it was the turn of the program’s four orchestras, which shared a program at Merrill Auditorium.

The university’s youth ensemble program is not a free service. Families pay $300 a year for a young musician to participate (there are reductions for multiple family members). Most also likely pay for private music lessons. For anyone interested in becoming a musician, professionally or not, ensemble playing is a vital skill; in fact, one could argue that the collaborative skills involved would benefit most people, even if they have no musical aspirations.

You might think that these groups, and their public concerts, are important only to those who have family members participating. But, unless you think that musicians sprout from the ether, fully formed, or that orchestral culture will simply continue on its own momentum, despite cuts in music education nationally, programs like these are crucial and worth keeping tabs on.

The groups the university fielded on Thursday vary widely in ability, but there was something to admire in the discipline each brought to its performance. The flagship ensemble is the Portland Youth Symphony Orchestra, conducted by Robert Lehmann, the director of string studies and orchestral activities at the University of Southern Maine. The 70-player Youth Symphony has operated since 1942 and is open to students ages 13 to 18.

Its short program, which closed the evening, included a vivid, carefully shaped performance of Mozart’s “Don Giovanni” Overture, an account of the opening movement of Dvorák’s Eighth Symphony distinguished by a fine string playing and a good balance of delicacy and energy, and three dances from Smetana’s “The Bartered Bride,” in which the wind and percussion playing was polished and sharply focused.

Some of the Youth Symphony’s wind players hold principal positions in another group, the Portland Youth Wind Ensemble, which also performed at a high level under the baton of Trae Blanco. Or, I should say, mostly under Blanco’s baton: Shostakovich’s high-energy “Galop,” which opened the set, was performed without a conductor, an impressive feat that showed Blanco’s confidence in his young players.

The set was otherwise devoted to a pair of accessible contemporary scores – Steven Bryant’s Coplandesque “Dusk,” in which the wind group produced a beautiful chiaroscuro texture, and Martin Ellerby’s more ebullient and descriptive “Paris Sketches,” which showed off the ensemble’s percussionists and wind players equally.

Deborah Dabczynski, a cellist in the Portland Symphony Orchestra, conducted the Portland Young People’s String Consort in familiar pieces by Marc-Antoine Charpentier (the stately Prelude from his Te Deum) and Edward Elgar (a movement from “Twelve Easy Pieces”), as well as a pair of short contemporary scores, Shirl Jae Atwell’s neo-Renaissance “Jongleurs” and Brian Balmages’ attractively energetic “Afterburn.”

These are musicians at a more larval stage of their development. They haven’t yet learned the mechanics of producing a rich, warm string tone, centered and with vibrato. But those things come, in time, and for a listener usually steeped in professional performances, it was fascinating and instructive to be reminded that great string playing has its roots in this straightforwardly innocent approach.

The musicians in the Portland Youth Junior Orchestra are a bit farther along, and many will find their way to the Youth Symphony. Ferdinand Liva, a professor of violin at the university – but best known to concertgoers as a member of the DaPonte String Quartet – led the group in an unusually slow but solid rendering of Benjamin Britten’s three-movement “Simple Symphony.”

Allan Kozinn is a former music critic and culture writer for The New York Times who lives in Portland. He can be contacted at:

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