It is not absolutely necessary. Some dogs just never get them and some yards don't appeal to fleas for whatever reason. That said, if you skip it you risk an infestation of your dog and your home. Then you do have to di something and it will involve a lot of work to get rid of them and potentially even more chemicals.
We currently use Sentinel which stops fleas from reproducing because they have never been a major problem for us (we haven't needed an adulticide often).
__________________ Crystal  , Ellie May (RIP)  , Rylee Finnegan  , and Gracie Boo🐶 |