REMOVE

1. hills
2. soil
3. plants
4. black-and-white film
5. 1961

WHAT

1. clouds (1)
2. fields (land) (1)
3. horizon line (1)
4. landscapes (representatio … (1)
5. silhouettes (1)
6. sky (1)
7. sunlight (1)
8. trees (1)
9. Visual Works (hierarchy n … (1)
10. woods (plant communities) (1)

WHO

1. Campbell, Sandra L. Still (1)
2. Sandra L. Still Campbell; … (1)

WHEN

1. after 1961 (1)