Charles Ellicott Commentary Genesis 30:37

"And Jacob took him rods of fresh poplar, and of the almond and of the plane-tree. And peeled white streaks in them, and made the white appear which was in the rods." — Genesis 30:37 (ASV)

And Jacob took him rods ... — Jacob’s plan was to place objects of a speckled color before the ewes and she-goats at breeding time, and as he put them at their watering-place, where everything was familiar to them, they would, with the usual curiosity of these animals, gaze intently upon them, with the physically certain result that many of them would bear speckled young.

Poplar. — Really, the storax-tree (styrax officinalis). “This,” says Canon Tristram, “is a very beautiful perfumed shrub, which grows abundantly on the lower hills of Palestine.” The word occurs elsewhere only in Hosea 4:13, and the idea that it was the poplar arises solely from the name signifying white; but this epithet is even more deserved by the storax, “which in March is covered with a sheet of white blossom, and is the predominant shrub through the dells of Carmel and Galilee” (Natural History of the Bible, pp. 395, 396).

Hazel. — Hebrew, luz (Genesis 28:19), the almond-tree (amygdalus communis). Dr. Tristram (Natural History of the Bible, p. 358) says that he never observed the true hazel wild in Southern or Central Palestine, nor was it likely to occur in Mesopotamia. The almond is one of the most common trees in Palestine.

Chestnut tree. — Hebrew, armon, the plane-tree (platanus orientalis). “We never,” says Dr. Tristram (p. 345), “saw the chestnut in Palestine, except when planted in orchards in Lebanon; while the plane-tree, though local, is frequent beside streams and in plains.” The tree is mentioned again in Ezekiel 31:8.