What is the author's style in American Primitive: Poems by Mary Oliver?

The language used in this collection of poems by Mary Oliver is very diverse. Mostly it is informal and abstract. Occasionally, it is more concrete. Sometimes, Oliver uses her poetic license to diverge from the path of grammatical accuracy, yet her poems retain their fluidity and ease in reading. Some of the poems contain action while others are purely speculative. Some poems take place in the present, others in the past.