EAsT camPUS

You can find a helpful message in the letters you see on the nodes.

Read the letters from left to right to find a helpful message (it begins BE QUICK...)

Additionally, the strange capitalization in the title is intentional (and is how students sometimes refer to East Campus, see e.g. http://ec.mit.edu/about)

The message suggests reading the name of the north section of the west parallel of EC. The name of that section is "Wood" (which you can find on the EC website or on Google Maps), and this word is relevant to the rest of the puzzle.

Each answer can be split into two interleaved words (much like the title).

Trace each answer up the edges of the tree, going left if the letter is part of the wood-related word and right if the letter is part of the non-wood word (the left edges are brown to disambiguate the direction). Each answer should pass through exactly three letters.

Each of the 21 letters the answers pass through is distinct from A-U.

Use the letters A-U on the tree to order the letters on the corresponding words that pass through them to spell out the final answer.