Great colour contrast, as pointed out by others, but the yellows seem unnecessarily subdued, perhaps by a passing cloud. The yellows should be singing, given the kind of day shown in the photo. Try increasing the Exposure by ½ a stop or so. This might mean reducing the whites to avoid blow out, but I think you'll end up with a more dynamic photo without increasing the saturation (which us another method to make the yellows brighter, but would also result in artificial colours).