What does Genesis 30:36 mean?

Laban has accepted Jacob's proposal that all of the mixed-colored sheep and goats and all of the black lambs born from this point forward would be his (Genesis 30:25–34). This would have been an extremely good deal for Laban: these "off-color" animals were relatively uncommon, and not as prized as the pure-colored animals. Not content with simply getting a great deal, though, Laban immediately cheated. He quickly removed all of the mixed-colored sheep and goats and black sheep from his flocks and gave them to his sons (Genesis 30:35). This, of course, is to ensure that there is almost no chance of Jacob getting any wages, at all.

Now, to further seal up his underhanded plan, Laban moves all those mixed-colored animals three day's journey away from the rest of the flock of solid white sheep and solid black goats. By this, Laban is ensuring that no wandering animals from the main flock will end up mating with a mix-colored animal or a black sheep. From his experience of owning large flocks of sheep and goats, Laban understand that he has now vastly reduced the odds of many mixed-color animals or black sheep being born out of the main flock. Those that will belong to Jacob should be very few in number.

Obviously, Laban is neither a gracious boss nor a caring father-in-law. In fact, he's a blatantly greedy fraud. Even his own daughters, who are bitter rivals (Genesis 30:1–24), will later unite in an opinion that their father is unworthy of further obedience (Genesis 31:14–16).

But Jacob has a plan of his own, one we will later learn is fueled by another dream from God (Genesis 31:10–13).