Basic agricultural improvement. Available from the start of the game. * Constructed on: * Plains, grassland, desert * Hill and tundra (only if adjacent to fresh water) * Wheat bonus resource * Effect: * +1 Image:20xFood5.png Food * +1 additional Image:20xFood5.png Food on fresh water tiles after researching Civil Service * +1 additional Image:20xFood5.png Food on non-fresh water tiles after researching Fertilizer