Canada. Consider the images our great sprawling neighbor to the noreth conjures up. (I'll pause here while vistas of mammoth lakes and mountains, snow and wild life, miles of prairie wheatfields, big blue skies, the Royal Canadian Mounties, and the Montreal Olympics fill your mind).

Now consider this one additional fact and see if that image radically shifts: Some of the most influential pop singers and composers in music today were born and reared in Canada -- in places like Nova Scotia, Montreal, Orilla and Saskatoon. And without these people, American popular music would have lost an honesty and quality that it probably never would have achieved.

There are the smooth-sounding country songs about everythign from truckers' cafes to salmon in a stream to flies in a bottle from Ian (Tyson) and Sylvia ("Greatest Hits," Vanguard 5-6 and 23-4; "Best of..." Columbia 32516); the fundamental decency of singers like Gene MacLellan (Capitol 11535) and the husky-voice, dynamic star, Anne Murray ("Love Song" Capitol 11266 and "Keeping In" Capitol 11559); Hank Snow's special brand of country that fits perfectly into Nashville (RCA Victor 3478 and 4798).

There are the night-time wails of Montreal's Leonard Cohen ("Best of..." Columbia 34077) and the bold sensitivity of Neil Young, who in nine Reprise albums, covers the pop music gamut having influenced a whole grab-bag of American and English groups (Reprise 6349, 6383, 2151 among others).

Gordon Lightfoot, considered by many to be the best folksinger in popular music, is constantly relevant, accessible, poetic, technically brilliant. In his five United Artists albums (from the first, United ARtists 6487 in 1966 through the "Best of..." collection, United Artists 6754) and his eight Reprise albums ("Gord's Gold Reprise 2237 and "Summertime Dream" Reprise 2246 are the most recent), Lightfoot, the traveling folksinger who has written about 400 songs, continues to be a prolific force in the international pop music world.

The newest gifts from Canada are Kate and Anna McGarrigle, two French canadian sisters who have, in just two years, been hailed throughout the Western world. Their first album, Warner Brothers 2862, won rave reviews and many awards; pop singers rushed to their side to offer appreciation and record their songs (Linda Ronstadt made "Heart Like a Wheel" into an enormous hit, Asylum 1092; Maria Muldar [sic] did the same with the sisters' "Worksong," Reprise 2235).

Now the McGarrigles have a second album -- "Dancer With Bruised Knees" (Warner Brothers 3014) -- and the sound is better than ever. Listen to Anna's version of "Heart Like a Wheel" backed by sister Kate and a third sister, Jane, with guitar, banjo and organ. It's simply beautiful.

But when you mention Canadian singers, there is still only one who heads the list and that one is Joan Anderson. If anyone remembers Joan Anderson at all, it was as Myrtle's rebellious daughter who lived in Saskatoon, a place situated in the middle of the prairie province of Saskatchewan.

Miss Anderson was a not-very-aggressive student who spent her time sketching Indians and waitressing tables in a coffee house. She learned to play the guitar and discovered that she could put words together to form interesting ideas. Soon after, this prairie-fresh girl of 19 dubbed herself a professional musician, married a cabaret performer from America named Chuck Mitchell, traveled to the United States -- and became Joni Mitchell.

Joni Mitchell, nee Anderson, eventually escaped to New York -- trying to recover from a broken marriage. She discovered both a fantasy world of music and children, and a real world of lonely and demanding lovers, of people isolated in New York's busiest places. That experience was captured in Mitchell's first album in 1968 (Reprise 6293), an album that brought her into the national spotlight.

By 1969, there was a new generation of listeners and Ms. Mitchell was there to write its anthem -- "Woodstock." The song and the generation made her a national celebrity.

That conflict is one of Ms. Mitchell's favorite motifs -- self-reliant heroines grappling with the chains of sexual and romantic convention. "Blue" (Reprise 2038), "Clouds" (Reprise 6349), "For the Roses" (Asylum 5057), "Ladies of the Canyon" (Reprise 6376), "Court and Spark" (Asylum 1001, her first Asylum album which emphasized the musical side of her still struggling with the concept of romance versus reality) have a confessional intimacy combined with a kind of journalistic detail and characterization that is surprising.

(If you want to hear Joni Mitchell in "live" concert, there is "Miles of Aisles," Asylum 202, with few frills and the L.A. Express).

Ms. Mitchell, like most folk singers including her compatriot Lightfoot, uses the concept of travel as a fundamental metaphor. Saskatoon is the hometown she left, and Los Angeles may be the one she has since adopted, but movement is her symbol for freedom -- freedom threatened by any kind of love or commitment. Still, she knows better than anyone else that this life of free will can be a lonely one and unfilled despite "a grocery list of men I've liked or loved or left behind."

"Hejira" (Asylum 1087), her newest album, extends the travel metaphor beautifully as a metaphor for life in general. The albums title reveals much -- it means the start of the Mohammed era when Mohammed tried to excape persecution by migrating from Mecca to Medina. The Koran calls such emigrants honored persons, "Muhajirun" -- emigrations of the faithful.

This concept of honor and dignity in being a refugee from one's home (or love nest) is a Mitchell passion and in "Songs for Sharon" [sic] she shows the doubts and longings that go with the nomadic state. Yes, there are lovely, lonely landscapes to discover but at what price? The images of Ms. Mitchell traveling from place to place (both inside and out) haunt every song in the album.

Lately, Joni Mitchell has been experimenting. "Hissing of Summer Lawns" (Asylum 71051) was a very different album that scared some people away because its rich musical thoughts were covered over by lapses in musical taste. "Hejira" brings her back into the mainstream of popular music where her ideas are always welcomed.