REMOVE

1. trees
2. houses
3. plants
4. porches
5. barns

WHAT

1. exterior views (1)
2. forests (plant communitie … (1)
3. landscapes (representatio … (1)
4. mountains (1)
5. railroad stations (1)

More 

WHERE

1. Lake Louise, Alberta, Can … (1)

WHO

1. Clyfford Still; Still, Cl … (1)
2. Still, Clyfford (1)

WHEN

1. 1920 (1)
2. 1945 (1)
3. between circa 1929 and ci … (1)