REMOVE

1. soil
2. roads
3. barriers
4. bushes

WHAT

1. Visual Works (hierarchy n … (1)
2. barns (1)
3. black-and-white film (1)
4. exterior views (1)
5. farmers (1)

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WHERE

1. Alberta, Canada (1)

WHO

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

WHEN

1. 1940 (1)
2. 1940 September 8 (1)