Be careful with an ultra wide angle lens, they are not really for beginners. They are incredibly complex to use properly, otherwise you end up with incredibly boring photos where most of the picture is blue sky and green grass with zero structure. Ultra wide angle lenses are highly specific tools that see occasional use with a lot of care in composition.
If your thought process is along the lines of "I want a wider angle lens to fit more of this landscape in" then you are heading in a very bad direction. Such lenses are not about fititng more landscape into a picture, but about emphasizing perspective or getting close to a specific subject while maintaining background interest. The typically use would be to photograph a foreground subject such as an interesting rock, house, tree, elephant, combined with some midground subject (lake/forest/meadow), and a background vista (mountains, citiescape, cloudscape) but all elements need to be connected by some visual path like a river or road. This kind of composition is hard to achieve but when pulled off gives stunning results.
Otherwise I would take a general purpose lens. I think the Nikon 16-85 works well, 16-20mm on the wide end is plenty for more standard landscape work, and then 85 is also really useful. The middle ground has less value in landscape work. Longer also works well, I use a 70-200mm for a lot of landscape work, soemtimes much longer as well.
