I think looking at the basics would give you some answers.
From wikipedia:
Landscape comprises the visible features of an area of land, including physical elements such as landforms, living elements of flora and fauna, abstract elements such as lighting and weather conditions, and human elements, for instance human activity or the built environment.
There is no limitation on how you present the above elements, so any focal length can do the job ultimately. It is all about the story behind the photo. There is always at least one good reason supporting a great shot, either's it's an interesting object within it, a wonderful light source/shadow effect, some rare shapes, very eye catching colours, an unique perspective, an attractive composition and etc.
If you can take all the boxes above, you may create a fantastic shot (or may be a total disaster!!) no matter what focal length you use ;o)
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However, there is one thing wide-angle lenses can provide while tele lenses can't. It is the Perspective Distortion. For instance, take a shot of the a box at right angle to it with both lenses. If you fit the front of the box into the same space of the photo frame, you may see that face of the box looks very similar proportion between the shots from the lenses. But, any object behind the box looks distinctively different. The wide angle lens would try to put a lot more objects behind the box (scaling down) or fewer objects in front of the box (scaling up) into the photo, while the tele lens keep a fairly steady scale for any objects behind or in front of the box.
For me, since the wide angle lens perspective is unusual to my every day vision, I find it fascinating!! In contrast, the tele lens flatten the whole view and I find it a bit dull in general... that's why I often use wide angle lens for landscape shots. But of course, if the view I want to capture could be achieved with a tele lens, what could stop me from using it?!