The Stoner Ranch

The bank president mentioned running a 150 thousand acre ranch to Maria Stoner who inherited the ranch when her husband was killed in the botched hold up.

Since there are 640 acres in a square mile, 150,000 acres would be 234.375 square miles. If the Stoner ranch was perfectly square it would be 15.309 miles by 15.309 miles. If it was a rectangle twice as long as wide it would be 10.825 miles by 21.650 miles. If it was perfectly circular it would have a radius of 8.637 miles and a diameter of 17.274 miles.

I don't think it would be reasonable to travel more than 10 or 20 miles to Val Verde from the ranch house and back - though maybe frontier people thought that business trips of several days each way were normal. Thus I suppose that the border of the Stoner ranch was only a few miles from Val Verde, that the ranch house was only a few miles inside the ranch, and that the ranch had a rather irregular shape.

By comparison, the largest ranch in Texas, the King Ranch, has 825,000 acres of land, 5.5 times as large as the Stoner Ranch. As the map shows, it has a very irregular shape.

https://king-ranch.com/about-us/maps/