Yet its reception since its triumphant first performance at the 1949 Holland Festival has remained distinctly mixed. Where that fervent, if by no means uncritical Britten fan, Hans Keller, could declare the Spring Symphony "a supreme masterpiece", an equally sympathetic Michael Kennedy has complained that there are passages "where one is made uncomfortably aware of faltering invention, of the jam being spread very thin, of reliance on artifice".
Meanwhile, the debate continues as to just what kind of a piece it really is. A choral work - in which the full chorus only appears intermittently in six of its 12 sections? A song-cycle - split between three soloists? And how can a structure in which three of the four "movements" comprise diverse song-settings strung together be described, in any sense, as a symphony?
Such questions were already latent in the choice of texts. It has been generally assumed since Schubert that the larger unity of a set or cycle is helped by sticking to a single poet or single tone of voice. Yet, from his early "symphonic cycle" Our Hunting Fathers (1936) to a text partly gathered and partly written by WH Auden, Britten seemed recurrently drawn to the more disparate - and hence riskier - anthology principle. The Serenade for Tenor Horn and Strings (1943), A Charm of Lullabies (1947), the Spring Symphony itself, and the Nocturne (1958) are all settings of diverse poets, related only by subject or mood. Granted, Britten originally intended to base the Spring Symphony upon anonymous medieval Latin verses, which might have conferred their own unity of tone. But "a re-reading of much English lyric verse and a particularly lovely spring day in east Suffolk, the Suffolk of Constable and Gainsborough, made me change my mind". In the event, he came up with a selection of 13 poets, ranging from the anonymous "Sumer is icumen in" to an admonitory Auden meditation from the Thirties.
Then there is the matter of scoring. Britten asks for soprano, alto and tenor soloists, boys choir, symphonic chorus and large orchestra, including five percussionists and two harps. But he had never cared for what he called "the luscious tutti effect" of late-Romantic orchestration, preferring the clear textures of Mahler, Stravinsky and Shostakovich. With the experience of his first two chamber operas behind him, Britten was well on the way to a conception of the symphony orchestra as a collection of small ensembles.
There are a few elaborate tuttis in the Spring Symphony - in the icy opening setting of the wondrously vivid anonymous lyric "Shine out fair sun", for instance, or the bluffly festive Beaumont and Fletcher welcome to the month of May that comprises the finale. But long passages are accompanied by sub-sections of the orchestra or mere handfuls of instruments: the rapt setting of Henry Vaughan's "Waters above" that forms the centrepiece of the slow second movement features just solo tenor and a weightless scudding of violins. Coupled with the frequently pungent harmony, the effect is often a spare edginess of sound. With the arguable exception of the first-movement setting of Thomas Nashe's "Spring, the sweet spring" in which the "big harp" tutti accompaniment is indeed sweetened by a sustaining string quartet, Britten conspicuously avoids the kind of vernal haze of such earlier English evocations of spring as Delius's First Cuckoo or the rhapsodic Enter Spring by his own teacher, Frank Bridge.
Britten's first movement comprises highly contrasted settings of six different poets - Anon, Spenser, Nashe, Peele and Clare (cross-cut in one setting) and ending in the stately processional of Milton's "Now the bright morning star". The slow second movement flanks "Waters above" with Herrick's "Welcome Maids of Honour" and verses from Auden's "Out on the lawn I lie in bed" (challenging the work's title in another sense by evoking "the windless nights of June").
The scherzo-like third movement encompasses settings of Barnefield, Peele and Blake, and only the comparatively brief, though vastly inventive finale is through-composed. Careful analysis can uncover a number of tonal and motific connections between various of the settings. Yet rather than developing such links, Britten actually seems to play them down, emphasising the discontinuity between numbers by sharp contrasts of scoring and character. It is as if he had deliberately set out to test the enduring strength of the symphonic ideal by realising it anew in a manner that, on the face of it, seems to contradict all its traditional procedures.
If so, this may help to explain why the Spring Symphony has become something of a composers" work. Tippett certainly remembered the way Britten constructed his opening as a succession of quite distinct ideas for different sections of the orchestra which are then piled up on one another, when he came to compose his Concerto for Orchestra (1963) and at least two other substantial works reveal a debt to Britten's structure. One of them is Leonard Bernstein's polystylistic Songfest (1977), a six-movement setting of 12 American poets for six soloists, the jaunty finale of which opens with an upward-bounding theme that sounds like a direct tribute to Britten.
The other work was actually dedicated to him. This is Shostakovich's 14th Symphony (1969) for two soloists, strings and percussion, structured on poems about death by Apollinaire, Lorca, Rilke andKuchelbecker. At the premiere, Shostakovich experienced the grim requital of seeing one of his deadliest enemies start from the audience and drop dead on the spot. Only a model of complex suggestiveness could have helped to engender such utterly contrasting works as the Bernstein and Shostakovich, and one of the sadnesses of Britten's own early death is that he, too, was planning a follow-up in the form of a Sea Symphony for which he had already selected the texts.
Ultimately it is the qualities rare even in Britten for which the Spring Symphony is most to be cherished. Never before or after did he dare to exploit so wide a gap between fragmented foreground structure and implied background form. Yet, for all the disparate details, the cunning with which the sectional proportions are disposed, and the steely cogency with which the lines are drawn do finally yield an overall profile, a cumulative 40-minute sweep which, in retrospect, feels genuinely symphonic. Nor are those disparate details - the sensitised word-setting, the brightly astringent harmony, the rude vernacular incursions of whistling boys choir and feisty cow horn - to be less than relished. If the work only once touches on more troubling thoughts in Auden's allusion to 1930s Europe, it culminates in the most unalloyed paean of joy in all Britten - reasons enough to catch it at the Barbican.
Britten's `Spring Symphony', LSO/Previn is at the Barbican, London (0171- 638 8891), on Wednesday 10 March at 7.30pm