Traditionally common law legal systems had separate definitions for assault.
Is it illegal to assault someone on your property. If you are on someones property it is best to get their consent before recording. All forms of assault involve causing physical or mental harm to another person. Depends on your states laws.
Under the law of trespass if someone enters the property without permission you can ask them to leave. You do not have to hit someone to be charged with assault. The line here can be confusing but drug use is illegal even if someone is battling their addiction.
Especially if they were in the process of exiting the premises or property. All other criminal activity10 days. In some states you have whats called Stand your ground laws which means that you do not NEED to back away or try to avoid confrontation.
The person must pose an immediate threat to you or your property and you need to exercise proper use of force. In respect to this can you punch someone if you feel threatened. All other criminal activity3 days notice.
Illegal drug activity where perpetrator is not the tenant5 days notice. Even though it is illegal to discriminate against someone for their addiction to drugs or alcohol it is not illegal to protect your property from illegal activity happening on the premise. Depending on the circumstances assault is also an act found in criminal law that can be used to charge and prosecute a defendant to a criminal case.
So hyper-technically the old man spraying someone with water could be an assault I suppose if he intended to spray you and you found it offensive. Words alone are usually not enough to commit an assault and some sort of physical action is typically required. Once you remove your invitation and a person refuses to leave they become a trespasser and trespassing is illegal and you can use as much force as is necessary to move them off your property and you can call the cops to remove them if you prefer although the cops have no more legal powers to detain or eject they will just ENFORCE THE LAW.