Monsters in Trent Park

In my imagined garden (oh, say, an acre is enough...) I grow a grove of birch trees for the blue-tits and woodpeckers to pick at; in between the foxgloves in the shade, wooden carvings loom and try to scare unwary intruders.
Of course, they don't scare me; I am their friend and I secretly teach them to sing songs at dusk, the sound of their thin, grating woody voices merging with the waving sussuration of the leafy canopy above.