What's the difference between scenery and landscape? In what situations can I use them interchangeably?
The scenery/landscape at the school is beautiful.
Does landscape sound natural in the sentence above?
You would not use landscape in that way; the user asymptotically has explained why in an earlier answer.
What you could say, though is:
NOAD explains it like this:
So, if you want to point out that the landscapers have done a particularly good job of arranging the shrubs and caring for the flowers, then you could indeed say that the school has beautiful landscaping. (In fact, in that context, I believe landscaping is a better word than scenery.)
Scenery is a term with generally broader in meaning than landscape (which may encompass landscape). It often refers to indoor settings.
Merriam-Websters defines scenery as:
1: the painted scenes or hangings and accessories used on a theater stage
2: a picturesque view or landscape
3: one's usual surroundings [e.g.] needed a change of scenery
Landscape is generally much more focused on natural geography (although it may be humanly enhanced or supplemente):
1 a: a picture representing a view of natural inland scenery
b: the art of depicting such scenery
2 a: the landforms of a region in the aggregate
b: a portion of territory that can be viewed at one time from one place
c: a particular area of activity : scene [e.g.] the political landscape
Except for the third aspect of the second definition, which is somewhat metaphorical, the depiction reflects a natural place.
Scenery and landscape are very different. Landscape has a geographical connotation. It describes the structure of the land and its shape. Scenery describes what is on the land, like trees, greenery, etc.
Also, there are some some cases where landscape is a countable noun. Scenery is always uncountable.
Grammatically speaking, the only difference is that scenery is uncountable whereas landscape can be countable or uncountable.
Landscape refers to the natural or man-made features and geographical structure of an area of land.
On the other hand, scenery refers to the general appearance (which is merely what we're looking at without trying to analyze anything) or a view of a an area of land.
Therefore, landscape is more likely to be used when talking about large areas whereas scenery would be properly used when talking about a relatively small area restricted to what can fit within one's range of vision.
Since scenery is, almost, always used when referring to picturesque views and never collocated with negative adjectives or used in an unfavourable context, I assume its most proper use would be when speaking from a subjective perspective. Landscape, on the contrary, is more of a technical term, that can be used both subjectively or objectively.
So to answer your question, yes, they can be used interchangeably, but they don't convey the exact same meaning moving from a context to another.
Grammar aside, here are some interesting points to consider:
scenery: the natural features of an area, such as mountains, valleys, rivers and forests, especially when these are attractive to look at (Oxford Learner’s Thesaurus 2008), cf. mountain/coastal scenery. That's why we usually talk about the lunar landscape and not scenery.
landscape: the land and features that you see around you in the countryside, or in the city (Longman Activator). The Oxford Learner's Thesaurus adds, "when you look across a large area of land." Note that while scenery is natural, a landscape can be artificially created/designed/altered, cf. landscape architecture, urban landscape, or unspoiled landscape.
Scenery is always nice (lovely, picturesque, gorgeous, fantastic, spectacular, or magnificent), whereas a landscape can be barren, bleak, harsh, or desolate.
The authors of the Longman Dictionary of English Language and Culture (2005) say the following: