ANNE'LL TELL you about Poco. At the drop of a hat. She's told me about them more often than almost anything I can think of, except the fact that the Butterfield Blues Band played her senior prom at Scarsdale High School in 1969. For Anne was one of those who clapped until their hands were raw at the old Tea Party close to two years ago, waiting for an encore from Poco that never came.

Taking this an an indirect recommendation, I saw their Sunset Series show last year on Boston Common, and was treated to the best show to come off that stage during a summer that featured the Allman Brothers and Faces, among others. I bought Poco albums, and waited to see them again.

WBCN's Charles Laquidara loves Poco's music almost beyond the legal limit. So whenever they come into town, he introduces them. It's just as well. George Davis couldn't do them justice. Besides, Laquidara's liner notes to their live album, Deliverin', are as adequate a description of Poco as any I've ever seen, "Laughing- eyed, high-bouncing Poco--creating images of green hills, amber fields, rolling white clouds, and a balanced planet..."

Poco makes music that's best suited to the stage; their complete irrepressibility just doesn't come across as well on record. The roots of the music lie in Buffalo Springfield's Los Angeles rock of the late sixties. Since the Springfield was burdened with more talent than it could ever sustain, it had to collapse, and when it did, the boys in the band went separate ways. Stills and Young went on to sometime solo careers. Furay and Messina formed Poco, to get a little closer to the country than they could with the folkrockers. Poco, after a very slow start, in which every copy of their first album for Epic was badly pressed went on to be the complete success that Stills and Young together couldn't match. (Stills's solo has lapsed into self- indulgence, and I never could stand Neil Young's voice or his electric guitar playing.)

The songs played at Boston Common on August 9 have in common a pervasive country flavor, the flavor that Furay sought in leaving the Springfield for Poco. The sets that used to begin with the irrepressible rock 'n' roll feeling of "C'mon," start with the shit-kicking, finger licking goodness of "Hoe- Down," in acknowledgement of Poco's antecedents, "Well, I'm goin' to a hoe-down--And kick up my heels--Go all night and never slow down--Yes, I love how it feels." Three more songs were played in rapid succession: "It's a Good Mornin'," "Railroad Days," and "Old Forgiver," gone almost before they could sink in. "It's a Good Mornin" is country funk, the hard core of the Poco music, "Railroad Days" and "Old Forgiver" belong to new guitarist Paul Cotton, who replaced tour-weary Jim Messina about a year ago. Cotton's work is more rock 'n' roll musically than Furay's, and his lyrics lean towards introspection.

FURAY'S BALLADS are infused with country sentiment. Both he and bassist Timothy Schmit write songs of unrequited love of slightly less fervor than Tammy Wynette's "D-I-V-O-R-C-E" (with similar arrangements.) Songs like "What If I Should Say I Love You," with very large organ sounds coming from Rusty Young's pedal steel guitar, and final choruses of shouting begin to combine elements of rhythm and blues with the country arrangements. But Poco wraps each song in its own harmonies; because it is one of the few groups with four blendable voices (nobody can deny Crosby, Stills, et al's problems with harmony.)

Poco is just about all country rock music made by deceptively good musicians. The most significant improvement over last year's performance is the emergence of Paul Cotton as a lead guitarist, allowing the band to stretch out some of the songs. "Keeper of the Fire," with its insistent rhythms, and the stretched out "C'mon," now closing the show, gave him a chance to show his abilities. Cotton is not Dicky Betts, or Eric Clapton, but his rock lines, though predictable, are more than adequate. He's also a very fine country rock guitarist, a genre which demands special talents, particularly the ability to refrain from holding each note, blues style. His work on "Good Feeling," the band's most recent single, was excellent, remaining in the upper register of his instrument, but neither repetitive nor boring--a considerable feat considering the rock guitarist's preoccupation with high notes. With him, "C'mon," once a country-styled, light opening tune, becomes slower, much more chord-oriented, in short, more rock 'n' roll.

Cotton's electric influences have far from absorbed the band's other styles. Poco has long included an acoustic segment in their shows, pickin' their way through "You Are the One," "Honky-Tonk Downstairs," and their medley of "Hard Luck," "Child's Claim to Fame," and "Pickin' up the Pieces." The acoustic songs, particularly "Honky-Tonk Downstairs," retain much more country feeling than the electric music. These songs are Rusty Young's, and he acknowledges his pedal steel predecessors with some of the purest country steel guitar outside Nashville on "Honky-Tonk," and his own instrumental "Grand Junction," with its simple progression, and Flatt and Scruggs pickin' and grinnin' overall feeling. Paul Cotton's filling lines were excellent, and once they played a short line in unison, so well, that it drew a smile from Rusty, normally the most dour and visually understated of the band.

Rusty Young's steel and dobro playing is the instrumental core of Poco. His strength is his willingness to explore the rock possibilities of his country music instruments. From the steel, he pulls the Hammond organ sound vital to the ballads by playing through a Leslie tone cabinet, the standard Hammond amplifier. He's content to play the dobro through a wah-wah pedal, making "Good Feeling" sound like it's being played in a wind tunnel. Yet he can also provide country licks that would do the folks at the Grand Ole Opry proud.

BUT POCO REALLY functions on Richie Furay's limitless energy. Furay is the embodiment of how much fun it is to play rock 'n' roll for people. He must be a joy to play lead guitar for--he's one of the finest rhythm guitarists playing. Laugh not--playing good rhythm is tough, because you're responsible for pushing the lead guitarist to whatever heights he's trying to achieve, as well as keeping the music on an even keel by keeping the time and most of the beat, and most importantly, filling out the sound as though there was a horn section. Ask Keith Richards, he's the best around. But his energy and his unbounded onstage joy carry Poco, and seep into Timothy's bass playing. George's drumming, and Paul's guitar work, resulting in five people chanelling their creative energies into the joy of making music for people.

Poco's live show is an hour and a half of good, solid, adolescent fun. Good-time music, as homemade and homegrown as the assemblage that's the cover of their latest album. An encore is just icing. Yet, from last year, I knew their encore highlights their show. It's so theatrical--five minutes of screaming, shouting, chanting applause, with a personal attempt by the MC that finally brings them back, and into "El Tonto de Nadie, Regressa," 27 minutes that proves their musical expertise. The song is a montage of tempo changes, and a collage of guitar styles, blues, bluegrass, and pure country. Paul's lead guitar structures and organizes the piece. Timothy Schmit's sense of the bottom of the sound, and the variety of things that can be played, while maintaining the all-important bottom, is staggering, as well as his instinctive knowledge of Paul's tendencies on guitar. Richie just chords his eyes out, and pushes the band. George is the perfect rock drummer, a flamboyant flurry of wrists and arms while playing precise rock tempos.

"El Tonto" is Rusty's song. He revisits each of the sounds that can be pulled from a steel guitar, particularly its use as an organ, and a vibrato guitar. Until the last five minutes, which are his to do with as he pleases. At which point he goes completely crazy, as does the band, and rips off Hendrix acid guitar licks and glissandos, complete with hand gestures. He knocks over his chair, and plays on his knees, and then he plays pedal steel with the chair. More Hendrix; then feedback; and finally some Moog licks. The element of surprise is as effective as the sheer wildness of the music. The listener is utterly destroyed. And the song is over. Poco leaves in arm-wrestling, hugging disarray.

This band drinks coke onstage. Timmy Schmit brings forth his daughter before the encore and introduces her. His wife watches the baby in her stroller throughout "El Tonto."

Poco's so folksy that they just naturally appeal to that romantic, simple soul that resides within a lot of us: you gotta like them just for their attitude of easy rollin' good country fun. Not that they're antiseptic, God knows, just cleaner than most. Though I admire them for that alone. Besides. Anne's never been wrong about a group yet. She and her friends practically made Elton John.