My chickens peck me- why?

[Tjhotmer]

Mine scratch with their beak, well at least the oldest one does, the others just peck. But it's quite painful what she is doing. Im just curious if this is angry behaviour because she doesn't do it alk the time, but when she does I have to push her away. To which she just comes right back. It's usually to my legs and stomach area, and she scratches with her claws as well, as if she is digging for more food inside of me.

 

[Terrik0750]

I have one that pecks at me and will jump on my back if I am crouched over. She will go after my toes if I am in flops. She is definitely top hen in the flock. She is very bossy and demanding when I have treats. She won't let my younger birds, who have just reached that age where they are becoming confident enough to approach me, get close.

Is there any way I can tone down this behavior? She has also started chasing my car part way down the driveway and that worries me a bit for her safety.