Between admiring staring at the little bush and eating, he's not paying much attention. It doesn't dawn on him for a moment that she's yammering on about trees or whatever. When it does, he's taken just slightly aback.

Who is she even talking to? Him? Surely she's not expecting him to answer. Because he doesn't. Just keeps eating his pastries and watching her pace around and ramble, offering nothing more than a little raised eyebrow.