REMOVE

1. groves (plant communities)
2. branches (plant components)
3. trees
4. 1960

WHAT

1. Visual Works (hierarchy n … (1)
2. artists (visual artists) (1)
3. automobiles (1)
4. black-and-white film (1)

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WHEN

1. 1970 (1)
2. between 1960 - 1970 (1)