You might want to take a look at the relevant statute:
- JimPC § 30.05. CRIMINAL TRESPASS. (a) A person commits an offense if he enters or remains on or in property, including an aircraft or other vehicle, of another without effective consent or he enters or remains in a building of another without effective consent and he:
(1) had notice that the entry was forbidden; or
(2) received notice to depart but failed to do so.
(b) For purposes of this section:
(1) "Entry" means the intrusion of the entire body.
(2) "Notice" means:
(A) oral or written communication by the owner or someone with apparent authority to act for the owner;
(B) fencing or other enclosure obviously designed to exclude intruders or to contain livestock;
(C) a sign or signs posted on the property or at the entrance to the building, reasonably likely to come to the attention of intruders, indicating that entry is forbidden;
(D) the placement of identifying purple paint marks on trees or posts on the property, provided that the marks are:
(i) vertical lines of not less than eight inches in length and not less than one inch in width;
(ii) placed so that the bottom of the mark is not less than three feet from the ground or more than five feet from the ground; and
(iii) placed at locations that are readily visible to any person approaching the property and no more than:
(a) 100 feet apart on forest land; or
(b) 1,000 feet apart on land other than forest land; or
(E) the visible presence on the property of a crop grown for human consumption that is under cultivation, in the process of being harvested, or marketable if harvested at the time of entry.