Swing Set Blueprints Is A Swing Set Considered A Permanent Fixture??

Is a swing set considered a permanent fixture?? - swing set blueprints

I live in Massachusetts and the daughter of my landlord gave me a hard time. I want to put a swing in my garden and my host told me (unwritten), was the Fiin, and now said her daughter, she did not know that I can not. My question is, is considered a swing as a permanent, legally or I may say so, because it was a toy for my son and not an integral part of the property?