Clearing Brush Again?

Flight Lands Safely After Hijack Alarm
  WASHINGTON -- A New York-bound passenger jet was diverted to Canada on Friday after sending out a false hijacking alarm. It landed safely in Nova Scotia and resumed its flight to John F. Kennedy International Airport.
  ....
  White House press secretary Scott McClellan said the president was briefed about the plane incident while clearing brush on his Texas ranch and was being kept apprised of the situation.
[emphasis added]

How much brush can one ranch have? Maybe the previous tenants were brush farmers.