With space at such a premium in Manhattan, New Yorkers are accustomed to thinking vertically when it comes to housing. Now bees are getting in on the action. David Graves, an urban beekeeper, tends his hives far above the bustle of New York on rooftops throughout the city. His buzzworthy honey gets rave reviews for its delicate sweetness and for the relief it offers allergy sufferers. But with Colony Collapse Disorder threatening his livelihood, we’re left wondering what a world without honey bees would be like. Not so sweet.