quacky

adjective3

1. •
   Fraudulent; characterised by or using the methods of quackery.

   • The Doctor says that some of the quackiest of the quacks are in the army. — 1919
2. •
   That resembles the quack of a duck.
3. •
   (US) Infested with quackgrass.

   • After the first hoeing of a quacky crop, it is often well to go over it lightly in the middle of a hot day, just skimming the surface of the soil, and cutting off the young grass. — 1859