The purple paint statute (Section 569.145 of the Revised Statutes of Missouri) allows Missouri landowners to mark trees or posts with purple paint as a warning to would-be trespassers. It fulfills the same function as a “no trespassing” sign, a fence, or telling someone not to come onto your property. Since they can’t be taken down, destroyed or stolen, purple paint marks are cheaper and more economical to maintain.

The law does not require that property marked with the purple paint also be fenced; unless, of course, you or your neighbor(s) raise livestock along the property line(s) in question.

Under Missouri’s law:

•  Any owner or lessee of real property can post property with the purple paint marks.
•  Purple paint marks must be placed on either trees or posts (the statute does not specifically allow the option of placing paint marks on buildings).
•  Vertical paint lines must be at least 8 inches long (the statute does not mention a maximum length).
•  The bottom edge of each paint mark must be between 3 and 5 feet off the ground.
•  Paint marks must be readily visible to any person approaching the property.
•  Purple paint marks cannot be more than 100 feet apart.

The statute provides that any person trespassing onto property marked by purple paint can be found guilty of a first-degree trespassing charge. Any unauthorized entry onto property marked with the purple paint is considered a trespass. First-degree trespassing is a Class B Misdemeanor, with potential punishment of a maximum $500 fine and/or a maximum of 6 months in jail.

Other violations which would subject a trespasser to first-degree trespass are (1) entering a property posted with “no trespassing” signs, (2) refusing to leave property once told to do so, and (3) coming onto land fenced against intruders.

Landowners can purchase purple boundary posting paint at hardware stores across the state. Several paint companies have formulated a latex semi-paste product for the specific purpose of marking property. The paint can be applied in semi-paste form or sprayed once thinned.