Between 1866 and 1888 some six million head of cattle were driven north from Texas. Why did the long drive come to an end?

1. 1. The cattle boom is dated to its height in 1885. 2. 2. After that the range became too heavily pastured to support the long drive. 3. 3. At the same time the country was beginning to be criss-crossed by railroads. 4. 4. Farmers then staked homestead claims and fenced them with barbed wire, which closed the open range. 5. 5. Drought and a beef price collapse are not given as causes here. 6. 6. No law banning the drives is mentioned anywhere, so the fourth option adds a cause that is not there. _Source: An Outline of American History (U.S. Information Agency, 1990, public domain), section OPPORTUNITIES OPEN IN THE WEST_