REMOVE

1. green
2. yellow
3. blue
4. red
5. houses
6. farming

WHAT

1. Visual Works (hierarchy n … (1)
2. birds (animals) (1)
3. exterior views (1)
4. geese (animals) (1)
5. plants (1)

More 

WHO

1. Clyfford Still; Still, Cl … (1)
2. Garske, Patricia; Patrici … (1)
3. Still, Clyfford (1)
4. Still, Patricia Alice Gar … (1)

Less

WHEN

1. 1956 (1)
2. c. 1956 (1)