The intent of that law is to prosecute people who "SWAT" someone
The problem with laws like this is the ACLU gets ahold of it and uses it to protect vagrants. Who can claim they are being discriminated against because they are homeless. Those discrimination and harassing clauses in the Ore. law open doors. As a property owner, you don't want to be paying lawyers to fight this. Better you plant areas with stinging nettles.