REMOVE

1. trees
2. plants
3. labor
4. soil

WHAT

1. Visual Works (hierarchy n … (1)
2. black-and-white film (1)
3. farmers (1)
4. farming (1)
5. fathers (1)

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WHERE

1. Killam, Alberta, Canada (1)

WHO

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

WHEN

1. 1938 (1)
2. 1942 (1)
3. circa 1940 (1)