What your question and the snowmobile question have in common is trespassing. I find it interesting that the attitudes toward this vary so much around the USA.
In Texas a warning is required. it can be by signage or certain markings, or it can be verbal. Once warned a person can be arrested.
At least in South Texas property is almost sacred. I was raised not to go on anothers land, signs or not, without first gaining permission. You didn't cut across someones property, even if it meant walking five miles around it.
Probably, everone has seen the old western movie, where the cowboys ride up to a ranch house, and advise the novice not to step down until invited to do so. I often have people drive up to my house and remain in their vehicle untill I go out and ask them to step out. It's common practice in rural South Texas.
Geting back to your question. I would check the laws of Arkansas and follow through. Even if it meant filing charges. They are not just trespassing, they are damaging your land.
ErnieB