Here's a note I found about it.
In this final tribute to Mahler's centenary celebration, the BSO will perform Benjamin Britten's arrangement of Mahler's delicate Second Movement from his monumental Third Symphony, titled What the Wild Flowers Tell Me. This work was composed at a time when Mahler had left the stress and politics of the Hamburg State Opera Theater to move to a small Austrian village to pursue his compositional career. He found solace in a small cottage next to a flower filled meadow in the Austrian countryside. The bucolic scenery inspired him to write one of his most carefree and gentle pieces. When Britten first heard a performance of a Mahler symphony he was captivated by the clarity and beauty in the music and this began a long relationship between Britten and Mahler's music. In the 1940s, a British publishing firm suggested to Britten to arrange this particular movement for a small orchestra so that English chamber orchestras would have the opportunity to perform Mahler's music.
Ivor