No Trespassing Signs Required in Texas?

The state of Texas details its no trespassing laws in its Penal Code in Title 7 Chapter 30.  I've included the most important sections of the document below.  In short, a fence on rural property alone is notice that the land should not be entered.  However, you can deter further and avoid any confusion by placing signs on your property.  

Trespassing is a Class B offense unless a firearm is involved and then it is a Class A misdemeanor.  The lowest misdemeanor is a C which is just punished by a $500 fine.  The highest is an A which can carry a $4,000 fine and jail time.  The full breakdown is included at the end of this post.

Penal Code Detail
A person commits an offense if the person enters or remains on or in property of another, including residential land, agricultural land, a recreational vehicle park, a building, or an aircraft or other vehicle, without effective consent and the person:
(1)  had notice that the entry was forbidden; or
(2)  received notice to depart but failed to do so.

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.

Class of Crime
 An offense under this section is:
(1)  a Class B misdemeanor, except as provided by Subdivisions (2) and (3);
(2)  a Class C misdemeanor, except as provided by Subdivision (3), if the offense is committed:
(A)  on agricultural land and within 100 feet of the boundary of the land; or
(B)  on residential land and within 100 feet of a protected freshwater area; and
(3)  a Class A misdemeanor if:
(A)  the offense is committed:
(i)  in a habitation or a shelter center;
(ii)  on a Superfund site; or
(iii)  on or in a critical infrastructure facility; or

(B)  the person carries a deadly weapon during the commission of the offense.

Punishment
Sec. 12.21.  CLASS A MISDEMEANOR.  An individual adjudged guilty of a Class A misdemeanor shall be punished by:
(1)  a fine not to exceed $4,000;
(2)  confinement in jail for a term not to exceed one year;  or
(3)  both such fine and confinement.

Sec. 12.22.  CLASS B MISDEMEANOR.  An individual adjudged guilty of a Class B misdemeanor shall be punished by:
(1)  a fine not to exceed $2,000;
(2)  confinement in jail for a term not to exceed 180 days;  or

(3)  both such fine and confinement.

Sec. 12.23.  CLASS C MISDEMEANOR.  An individual adjudged guilty of a Class C misdemeanor shall be punished by a fine not to exceed $500.

Texas Parks and Wildlife - Wildlife Management Coordinator

http://comptroller.texas.gov/taxinfo/proptax/pdf/96-354.pdf

While looking a property the day after Thanksgiving, I noticed this sign on a piece of property.  From what I can tell, this is a program offered by Texas Parks and Wildlife in which you work with TPWD to create a plan to make your property more habitable for wildlife and in turn pay lower property taxes. 

There are two requirements to be part of the program:

1. Your land must be qualified for agricultural appraisal under Tax Code Chapter 23, Subchapter D the year prior to changing to the wildlife management program.
2. The land must be used to generate a sustaining breeding, migrating, or wintering population of indigenous wildlife.

The landowner must perform at least three of the following seven activities:

1. Habitat Control - create or promote a habitat beneficial to wildlife.
2. Erosion Control - keep soil from eroding for the benefit of wildlife.
3. Predator Control - Manage predators to the benefit of the target wildlife.  Normally not needed.
4. Providing Supplemental Water
5. Providing Supplemental Food
6. Providing Shelter
7. Make Census Counts

The program involves making a plan which often consists of each of the seven activities.  The plan must be made in accordance with TPWD regional guidelines which provide generally expected activities for the various regions in Texas.  You can find your region using the following website:
http://tpwd.texas.gov/landwater/land/habitats/post_oak/regulatory/

When I purchase land, I expect it to be in the Post Oak Wildlife District.  Unfortunately, I don't see what is generically prescribed for each region online to determine how extensive the work would be.