Answer: Since there is no rental agreement and you (presumably) have not accepted any rent or other payments from him, he is technically a “squatter.” Under Oregon law, a “squatter” means a person occupying a dwelling unit who is not so entitled under a rental agreement (ORS 90.100 (43)). The “dwelling unit” in this case is the RV space. Occupancy by a squatter is not governed by the usual landlord-tenant laws under ORS Chapter 90.
This person is first and foremost a trespasser. As such, you should first try contacting the police or sheriff, explain the situation to them, and ask them to remove this person from the park. You should also ask them to issue a no trespass order so that if he returns, he can be arrested for trespassing.
Unfortunately, sometimes law enforcement officers are reluctant to remove squatters even when they have the lawful authority to do so (i.e., if the squatter lies and says he has paid rent to the park). In that case, you will need to resort to court action.
There is a “midnight move-in” statute (ORS 105.115 (1)(c)) that allows RV parks to immediately file an eviction case in court without notice if the owner or possessor of an RV places it on park property without the park’s prior consent. However, since the statute is very specific about applying only to “recreational vehicles,” this statute would not work in your case where the squatter has only a tent.
Fortunately, there is another statute (ORS 105.115 (1)(b)) that also allows a landowner to file an immediate eviction case when a “person in possession . . . is holding possession without any written lease or agreement.” When you file the eviction case at your county courthouse, ask for and fill out the eviction complaint form for a tenancy notcovered by ORS Chapter 90. In the section where you must indicate why the park is entitled to possession of the premises, check the “No Notice” box and write: “ORS 105.115 (1)(b) – Trespasser in possession.” (NOTE: The filing fee for this kind of case is more than a regular residential eviction case – $281 vs. $88.) After filing, the case will proceed like any other eviction case.
Finally, be aware that in rare instances, a court might decide that an eviction case is not the right kind of case to file in this situation (although in my opinion, any such ruling would be legally incorrect under this particular fact pattern). If that were to happen, you would likely need to file an ejectment case, which is similar to an eviction case, but takes longer and would usually require the assistance of an attorney.