Genesis 30:36

³⁴And Laban said to him, Let it be according to thy word.

³⁵And he separated in that day the spotted and speckled he-goats, and all the spotted and speckled she-goats, and all that was gray among the rams, and every one that was white among them, and he gave them into the hand of his sons.

— Genesis 30:36 —

³⁷And Jacob took to himself green rods of storax tree and walnut and plane tree; and Jacob peeled in them white stripes; and as he drew off the green, the white stripe which he had made appeared alternate on the rods.

³⁸And he laid the rods which he had peeled, in the hollows of the watering troughs, that whensoever the cattle should come to drink, as they should have come to drink before the rods, the cattle might conceive at the rods.