REMOVE

1. plants
2. rubbish
3. soil
4. workers
5. freight cars

WHAT

1. Visual Works (hierarchy n … (1)
2. airplanes (1)
3. black-and-white film (1)
4. boys (1)
5. coats (garments) (1)

More 

WHERE

1. Bow Island, Alberta, Cana … (1)

WHEN

1. 1912 (1)
2. 1920 (1)
3. between 1912 - 1920 (1)