Tree Cathedral

Imagine this. What would you call it? 

Place yourself on ground level in the middle of a circular area approximately the area equivalent to a regulation football field; or, say, half the size of an average city block. Around 25,000 square feet. Big. But, circular in shape.

Now, picture tall trees growing at close, precise spacing around the circumference of that round space. The trees are very tall. With broad branching canopies which grow into each other to make a cathedral-like vault, some one hundred or more feet over the ground below.

At very precise intervals the canopy of each tree sports two symmetrical openings, each shaped like chevrons. Window-like. The sun streams through.

And, on the ground floor, it's not covered grass; but with hard gnarled roots growing intertwined like snakes, everywhere. Almost completely covering the entire circular space.

Magical. Awesome. Terrible. 

What would you call it?