When the three of them came across a diverging path, Harry and Ron ran one way while Hermione ran the other way. It was too late to change their path, so they kept going on their individual way. The creature opted to follow Hermione, probably because she was alone. She ran as fast as her legs could carry, and then when she came across an area densely populated with low-hanging branches, she quickly made her way to hide in there for a while.