When Morten Lauridsen was growing up in Beaverton in the 1950s, students commonly headed out to the Tillamook Burn to plant trees. A few years ago, the composer returned to the once-barren site to see it now covered by towering firs.

Lauridsen's musical career has sprouted proportionately over that half century. Now the dean of American choral composers, his works are performed by choirs all over the world. He received the 2007 National Medal of Arts at the White House, and his works have appeared on more than 100 CDs. This weekend, he returns to his hometown for two concerts of his music with Portland State University's choirs and symphony.

Although he's lived in Southern California since the '60s, in a sense Lauridsen has never left the Northwest. One set of ancestors helped settle Bainbridge Island, while another pioneered eastern Washington, where he was born in 1943. Lauridsen graduated in the first class at Sunset High ('61), played in the band and sang in choirs, and considers himself a native Portlander. Each summer, he escapes L.A. sprawl to return to a primitive cabin he built in 1975 on Waldron Island, Wash. There, by light from kerosene lanterns, he completed some of the most beautiful choral music of the last century on a battered $50 piano. 

"The Northwest has drawn out of me some of my finest music," Lauridsen says. "You can hear that its serenity, calmness and beauty have crept into my music."

He's returned often to lecture at local universities, hear and participate in performances of his music. The first of 11 all-Lauridsen CDs was recorded by Portland's Choral Cross-Ties, who premiered his major cycle Les Chansons des Roses, inspired by the City of Roses. Another recent CD is titled Northwest Journey. 

Listeners cherish the lush, often soothing harmonies and rich inner lines of Lauridsen's music. Choirs admire it because "he really does understand the voice," says Ethan Sperry, PSU music professor. Sperry studied under Lauridsen at the University of Southern California, and created this weekend's programs with him. Sperry cites Lauridsen's deft use of jazz harmonies and fresh treatment of seemingly simple classical music devices as key to his music's appeal.

Both weekend concerts, with Lauridsen and other pianists accompanying the PSU orchestra and choirs, feature his enduring O Magnum Mysterium and Sure on This Shining Night. Friday's program includes selections from several of Lauridsen's classic choral cycles, plus his abstract Lorca settings, Cuatro Canciones. Sunday's show, which adds three church choirs and soloists including Paul Sperry and the Oregon Guitar Quartet, features his luminous Lux Aeterna, A Winter Come for voice and piano, and both the solo and quartet versions of "Dirait-On," the enchanting lullaby from the Rose songs. It's a wide-ranging tribute to and homecoming for one of the Northwest's finest composers.

SEE IT: First United Methodist Church, 1838 SW Jefferson St., 725-3307. 8 pm Friday and 3 pm Sunday, Feb. 25 and 27. $12-$17.