I'm in the US, so referring to that:
If you want to be on the safe side, you should notify the airport and avoid any ambiguities.
That said, the actual laws are a bit conflicting. The Causby case has been referenced a number of times which gives you the right to usable space over your own property, and it's hard to argue you can't use 10 feet. At first, the FAA authority was for navigable airspace, which probably wouldn't include your backyard either. However, that authority seems to have expanded lately.
With that said, I live on the inside edge of multiple maps 5 mile radius from a major airport. In reality, those maps start from the center of the airport, so I'm a bit closer to the end of the runway. I'm not in the typical flight pattern, but depending upon the winds I am occasionally close to the takeoff pattern, within 1/2 mile or so. When I am, planes fly about 2500 feet over my house (actually very rarely over my house, but over my neighborhood within site of the house). It should be noted, outside the 5 miles zone (via dji and airmap) they are only a few hundred feet higher. I do not fly when I'm in the flight pattern, even though there should be no issue.
A few times I flew from my backyard to about 150 feet, and did notify the airport, and they had no issue with it. However, a number of times I've flown at roof level or below to test firmware, filters, etc. and I do not notify the airport. The highest tree in my backyard is probably about 55 feet or so tall, and I've made my own personal rule that if I'm below my tree, that's my airspace and I'm not calling the airport, if I'm above, then I do. The reality is, if a plane that should be at 2500 feet is at 50 feet, it has other issues beside my 1 pound drone. I don't know if law would support me or not, and the airport has never told me not to fly when I do call, its just a convenience thing for me, as the airport wants me to call ops and the tower, so it takes a while, and more time than I want to spend for a quick couple of minute test.
So, to summarize the OP's question (assuming the US)
1 - No, the FAA can't track you
2 - You probably need to notify the airport if going by the letter of the FAA's rules
3 - Grey area if you don't and stay at 10 feet within your own yard
4 - I personally would not worry if staying at 10 feet, but some random guy (like me) on the internet saying it is ok, doesn't make it ok by law.