New city/first city, after filling all building slots, i researched farming. Once city leveled up to let me build a farm, i built the farm. After which i scrolled the map, moved my Sov. went back to the city, and clicked the build icon. After that only the destroy building icon appeared on the left side(no building icons showing), and the right side tabs were 'farm' and 'design', with info on the farm, and it also had left/right arrows that are used for side scrolling in the game.