... ...
"Pull up a bit of grass, Barry," said Ludo brightly, patting the ground beside him.
"No thank you, Ludo," said (Barry)Crouch, and there was a bite of impatience in his voice. "I've been looking for you everywhere. The Bulgarians are insisting we add another twelve seats to the Top Box." ...
I think in this context Ludo was asking Barry to sit beside him. The phrase "Pull up a bit of grass" is pretty close to "Pull up a chair". But does Ludo mean that Barry literally pulled up a bit of grass and sit beside him? How should we understand it in this context?