The noun capital can hold different meanings, and as always it is subjective what to choose to express a theme in a photo.
I like birch trees. I love the fine detailing from the stem, to branch to the twigs. From big to delicate. A birch can be intimidating, towering over me.
Looking up a birch gives me a feeling of humility. This photo is from 1979, a time when i was printing in a darkroom on paper. And loved big abstracts in monochrome.