I am in the process of buying new property it is only 10 acres but it has great character hill on one side then it all goes down to a bottom with a creek on the other side of the bottom ....on the plot it shows that it should be going into the corner of a pasture whoever owns that other part has at one point or another took the fence and left me the bottoms.. So they cut me out of a great hunting spot and also about 1/3 acre or a little more. My questions are...
What to do and what can I do

Get an official survey of the land
After that, if your property has been fenced then you can take action to correct.

get a land surveyor to complete a survey for you and go from there. if the "plot" you are referring to is a gps tax map, the lines showing your property line can be wrong, quite wrong at times. a surveyor will get it figured out for you.

In the state of LA, not sure about TX or other states, it can be disputed land and if the other landowner can show he has used it as his own for so many years the land "might" be his. On one of the leases we had here in LA several years ago, this happened with a private landowner and a timber company. The private landowner had part of land under fence and cleared for pasture that the timber company claimed as their own. It is listed as "disputed land" on the maps (or was 25 years ago when we had the land leased). I am guessing that the timber company didn't want to go to court for such a small amount of land, but neither did they just give it to the landowner either. But again, that is here in LA. Good luck with it.

Ed,
Same here in Missouri.
When my parents moved to Missouri there was a fenceline along their east border that my Dad continued to maintain (even restrung the wire a time or two). Lived there about 30 years when the property to the east was sold. Found out the fence was approx. 50 feet to far east (according to survey). Since Dad had records that he had maintained the fence for over 20 years (& that fence was already inplace when they arrived / purchased) the property between fence and parents actual property line became my parents property. Don't remember the term the county used but it was something like 'squatters rights without objection'. Ofcourse they now had to pay the tax on that portion from that date on.

Did you buy the land without a current survey? Fences do not follow current survey lines on old properties.

I was required to get a survey done before purchasing the property. It also showed a 1/4 acre of my property got fenced off by a new fence a neighbor put in.. didn't make a big deal of it but its such a small bit of property is why... if it was a good bit would have been a different story.. that being if there was something that could have been done

if a survey shows the property line in a different place then you can legally force that the fence be moved. you cannot force the fence be moved at the other guy's expense. you would at a minimum probably have to share in the cost of moving it. and or if he is relatively un-cooperative and disgruntled about it then you may need to just bear the cost of moving to move things along. it can be done, but it will cost you time/effort/money. The sheriff or something isn't going to come out and force the guy to move it for you.

I know this: It's better to go slow and be friendly about it than to make an enemy of a neighbor that you plan to be next to for the rest of your life.

First, get an official survey and then go compare that to the legal description on title and also compare to what the tax office has.
Then it might be time for some polite discussions with neighbors.

On the land my family owns there is an approx 18 acre area that doesn't have a perfectly clear title. But we have been paying the taxes on it for the past 25 years and the previous owner paid the taxes on it for 50 or more. There is a legal process that we can go through but it takes time and money.
The short answer is that if anyone ever shows up and can prove the title is theirs they have to cough up all the taxes we, and the previous owners, have paid. That might be more than the land is worth.

I am meeting the surveyor in the morning so I will find out more. I was told by bank I didn't need to get one. When I got across the creek and noticed the fence I figured it was time to get one right away

Update?