Perhaps I need to better calrify. Under texas penal law section 9.41 states a land owner can use reasonable force if summoning law enforcement is not a viable option or when the actor believes it is ultimately necessary to prevent or terminate trespass. Necessary force can go as far as firing upon trespasser or can be a simple as physically removing said trespasser.
However texas penal law section 9.42 states
A person is justified in using deadly force against another to protect land or tangible, movable property: (1) if he would be justified in using force against the other under Section 9.41; and
(2) when and to the degree he reasonably believes the deadly force is immediately necessary: (A) to prevent the other's imminent commission of arson, burglary, robbery, aggravated robbery, theft during the nighttime, or criminal mischief during the nighttime; or to prevent the other who is fleeing immediately after committing burglary, robbery, aggravated robbery, or theft during the nighttime from escaping with the property; and
(3) he reasonably believes that: (A) the land or property cannot be protected or recovered by any other means; or the use of force other than deadly force to protect or recover the land or property would expose the actor or another to a substantial risk of death or serious bodily injury.