Chop down and Cut back

Chop down verb - To bring down by cutting.

Cut back and chop down are semantically related. In some cases you can use "Cut back" instead a verb "Chop down".

Cut back verb - To make (something) shorter or smaller with the use of a cutting instrument.

Chop down and cut back are semantically related. Sometimes you can replace term "Chop down" with "Cut back", this phrasal verbs are similar.