We don't know about you, but when we read "Oread," we can't help but think of The Little Mermaid's Ariel. (You know, that scene, where Ariel lifts herself up on the rock and sings to her heart's content?)
This is what we picture when we read "Oread." A slight but powerful woman, perched on a rock, yelling out to the green sea to come closer. Whirl up sea. We want you to be part of our world. (Or so we imagine the Disney version of the poem might say.)
The gist here is that this is a poem with a natural setting. And since it's an imagist poem, that's all we get. Nothing complicated, just water and trees.